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^frtisi
DE LUXE EDITION
OF
^3yke's Automobile and Gasoline Engine Encyclopedia
Bound Willi G^niiino Leatbar Flexibla Binding —
OoM Letters.
Price $8.00
riH«"r.
(Add 46c to ««ad by iBsared mftil. If too much w« m\n refuDd dilTerwict,)
Owing to the frequent demand of ] our customers oe former editions , — a limited number of copies of I this edition will be bound with a i high grade flexible binding — but otherwise there are no changes. To those who have purchased this ] edition (not former editions) with , the cloth or regular binding^ we \ will exchange, if in good condi- tion, on payment of the difference j in price and transportation. As Btated, only a limited number of the flexible bound copies of thiflj edition are available.
Not« — If bcH>k It ft former edition add $B,00
*'*%"vir£*,{SSl^"^° DYKE'S MOTOR MANUAL phc* $2.00
All about StftiioiLary IntemiLl Oombustloa Engines (gas^ gaaolioef kerosene, oU) Mulne EnginM, Motor BoatB^ Motorcyclea. A Submarine^ also Gas Produeere are explained. Quite often the Automobile Eepairman or Owner ie ealled upon to diagnoie troubl#iL ^rj repair Stationary, Marine, Motorcycle BngiiieB— are you fully potted T Tbii Motor Maa-
ual will teach you— get it for a reference, if nothing more.
DYKfTS
MOTOR MANUAL | [ Motorcyclci.Mmi inr
Simplified f
IStiitii
PQltj illastr«t«d, 3S4
r<*tl*%l **>%<*%
-iHttl toAkVf -
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fWJinV, " ,37 COLOEN CATC AV t. yy
INDEX TO CHARTS
Giving the Page Number Each Chart Page is On.
I
8
8
4
5
6
7
9
9 10 U 18 18 U 16 16 17 18 19 80 80A 81 88 88 24 86 86 87 88 89 80 80A 81 88 88 84 86 86 87 88 89 40 41 48 48 44 46 46 47 47A 48 49 61 tt 68 64 66 86 87 68 69 60
a
71 7B
IT
1
8
8
4
6
6
7
8
9
14
16
80
84
86
28
38
34
88
40
48
44
60
48
47
62
64
66
60
68
70
71
62
64
66
74
76
78
80
88
84
86
86
90
88
94
93
100
108
106
108
109
116
118
116
121
122
124
186
186
188
189
180
181
188
188
186
187
189
140
188
141
144
OkM% Ptg«
78
74
76
76
77
78
78A
79
80
81
81A
88
88
84
86
86
86A
87
88
89
90
91
91B
98
94
96
96
97
98
99
99A 100 101 108 108 104 106 106 107 108 109
no
111
118
118
113A
118B
U4
116
116
117
118
119
180
181
188
188
184
186
189
180
181
188
188
188A
134
186
186
187
188
188
140
141
146 148 168 164 166 167 169 160 162 164 166 178 173 174 176 176 177 178 179 180 181 182 l83 184 186 188 190 192 194 196 198 204 210 214 216 218 220 222 224 226 228 230 234 286 287 238 239 240 241 244 248 262 264 266 268 260 262 268 264 268 270 278 274 276 278 280 881 888 888 884
OkM% PAff«
148 289
14SA
148B
1480
148D
144
146
146
147
148
149
160
i60A
161
168
168
164
168
169
160
160A
160B
161
161A
168
168
164
165
166
167
168
168A
168B
1680
168D
169
170
171
178
178
174
175
176A
290 291 292 293 294 296 298 302 d03 304 306 310 814 316 318 322 323 324 326 328 329 330 331 332 334 336 338 339 340 342 344 346 348 349 360 361 362 363 364 366 367 368
176AA 369 176B 360
176
177
178
179
180
180A
180O
181
181A
181B
1810
181D
188
184
186
186
187
188
188A
188B
1880
188D
188B
188F
188a
IHH
361 362 363 364 366 367 368 369 370 371 372 373 374 376 379 380 382 384 386 388 391 898 393 894
896 409 1887 408
OkM% Ptg« Oharl Pact
188K
188L
189
189A
190
191
198
198
194
196
195
197
198
801
808
808
808A
804
804A
806
206A
206AA
205B
206O
806D
205E
205F
205O
206
207
207A
207B
2070
207D
207E
208
209
210
211
818
818
814
216
816
817
818
819
880
881
288
888
224
224A
285
226
226A
287
888
229
280
231
288
886
886
886A
886AA
886B
8860
886D
886B
Vq. 1, paff« Ite; Va. S, pag*
887
887A
887B
404 406 406 410 414 416 418 426 428 480 429 484 436 440 442 444 446 460 462 460 462 464 466 466 67 68 72 74 76 76 ,78 79 480 481 482 483 484 486 488 490 496 497 498 499 600 502 604 612 513 614 616 334 586 537 688 539 540 648 543 644 546 546 550 558 664 566 566 567 568 669 560 661 668 668 664
889
840
840A
841
841A
848
848
84aA
84SB
844
844A
846
846
847
847A
847B
668
670 572 678 574 576 592 596 598 600 602 603 604 605 606 607 608
|
847BB |
609 |
|
8470 |
610 |
|
247D |
611 |
|
247DD |
618 |
|
247E |
613 |
|
247P |
614 |
|
2470 |
616 |
|
247H |
616 |
|
248 |
618 |
|
249 |
619 |
|
249A |
624 |
|
250 |
632 |
|
250A |
633 |
|
251 |
634 |
|
252 |
636 |
|
.£54 |
638 |
|
265 |
642 |
|
266 |
644 |
|
257 |
646 |
|
268 |
647 |
|
869 |
648 |
|
869A |
649 |
|
859B |
650 |
|
860 |
652 |
|
861 |
659 |
|
862 |
660 |
|
863 |
664 |
|
864 |
665 |
|
265 |
666 |
|
866 |
667 |
|
867 |
668 |
|
268 |
670 |
|
269 |
671 |
|
270 |
672 |
|
272 |
673 |
|
272A |
674 |
|
878 |
675 |
|
874 |
676 |
|
874A |
677 |
|
876 |
678 |
|
876 |
679 |
|
877 |
680 |
|
878 |
682 |
|
879 |
683 |
280A
880O
880D
880B
881
888
888A
888 88SA
684 686 687 688 689 690 692 693 694 696 698 699
Ohact
884
285
886A
285B
8860
886
886A
887
887A
288
889
890
290A
890B
890O
891
898
893
893A
293B
29SD
294
294A
295
296A
296
297
298
299
300
302
304
306
306
307
308
308A
308B
809
309Z
309A
S09B
310
311
312
S12A
313
314
814A
316
316
S16A
Pi«#
700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 720 722 724 726 727 728 729 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 748 760 751 762 754 766 758 759 760 761 762 764 765
Ford Snpplemtnt
817 776
818
319
820
821
882
888
384
886
386
826A
827
828
770 771 772 773 774 775 776 777 778 779 780 781
829 782
380 783
881 784
888 786
-88a; Va. i. 864*.
888 884
886
886A
886
887 888 889
840
841
848
848
844
846
846
847
846
849
860
861
868
868
864
865
866
867
858
359
360
861
862
863
864
865
866
867
868
869
869A
870
871
872
878
Addmii 874 875 876 877 878 379 880 881 382 S8S 384 886 386 387
Packa
Snpplm 389 390 891 392 898 394 895 396 397
AlrpUn« LllMrt7
Pg. 90f
Dyke's
Automobile and Gasoline Engine
Encyclopedia
TWELFTH EDITION
Second Run
Containing 532 Charts, Inserts, Dictionary, Index,
and Supplements on the Ford, Packard, Airplanes,
and Liberty *M 2" Engine.
TREATING ON
THE CONSTRICTION, OPERATION AND REPAIRING
OF AL'IOMOBILES AND (iASOLINE EN(;INES.
Also Trucks, Tractors, Airplanes and Motorcycles.
BY
A. L. DYKE, E. E.
OKIGINATOR OF THE FIRST AUTOMOBILE SUPPLY BUSINESS, PUBU8HSR OF THE FIRST PRACTICAL BOOK ON AUTOMOBILES AND MANUFACTURER OF THE FIRST FLOAT FEED CARBURETOR IN AMERICA.
AUTHOR OF
•DR. DYKE'S DISEASES OF A GASOLINE AUTOMOBILE;"
THE FIRST PRACTICAL BOOK ON AUTOMOBILES IN AMERICA, (1900).
"DR. DYKE'S ANATOMY OF THE AUTOMOBILE." (1904). "DYKE'S MOTOR MANUAL;" all about motorcycles, marine
ENGINES, MOTOR BOATS, STATIONARY GASOUNE AND OIL ENGINES.
0op7rifbt«d 1011-191219181914-1915 1916 1917 1918-1919 1920
By A. L. DYKE, ST. LOUIS. MO.
All Bifhti Reserred.
OopTriElit ProteeUd in Great Britain, all of her Ooloniea and Canada.
Entered at Stationers Hall, London.
Platei made, type aet and printed in U. 8. A.
All Bifbti Reierred.
PUBUSHED BY
A. L. DYKE, Publisher
ST. I.OUIS, U. S. A.
I f- 9-9:)
of lih
colored page imert in bmek <
first pcge flj leaf of book«
'or IHcMitiurT-
VtLge Wl.
n
TABLE OF CONTENTS
ss* so
Dtff«r«atUa aod B««Elllfl. . SI- 96
i^-<Ilfiteli«i^ UotTfnal Jomtft 37- 4i
# — Ttt**^'"* «f ftiw* ,,««^., . 4i^ 51
WStQIMEB. y»qMaariJ Ccnvtmctloii ...,_.*.., fiS- 71 •— PiiBcipte. IjocAtiim of Pirta.... 7S- d2
i^V&lv« Timing ,,., ,,..-.♦ 93-115
10— nftQ< Order ->.,... ..,_...,..,U6-120 U-^au, mgut wd Twitv# O^UndAr
.un-140
OoBVtrucUon , , .141-166
IS^-OBftmratar Adjuftaiinti 166-lBi
OOOZiPlQ Ain> LUBBIOATIOM*
.*-.. lee-iw
OUfl ftud QfViMi. . ,186^206
laMmON; OOm AKB BAMBST.
IS— l4>w Touilciii WT^UaoM. .906-S17
17^--aiffb T«ti^^a BfBtenui . . , .216-232
li^^Spmric Flag uq4 PoO Trtmblif . . .saS-Sil l^^Hodvm BAttary and CoU STstetos . 242-2M HO^Bilaf Ettn«w of tao Vartoiu OM
B^mmoM 866
I0NrnOK; MAGNETOa U— I^ow TttUloii. (Piliu:liil0 And Oom-
ftmctloa) ,.,,..., 26d-S67
IB— HlgJi TOsDfltoa (Xjoftdlnff tTpet d»<
ionbod) ,. 266-293
86— lnat«JiAtloii, 0»i« «tid AdJiiAmiot8.2M4-304 ii^-l«iatlcm Tuning , _ .30&320
ELEOTBIO BTSTElia 16— Baglno StArten .,..,...,...... .621-622
ii^Tlis Eloctxlc 8ta4l^lng Motor 393-331
i7— TtM G«nerKtar. (Source af CTor-
tm%} .,.__.. _ .332-656
iS— Typai of StartlQif and G«2iorAtliiS
HfitOimi uftod OQ lieadlng Qui S66'^^73
aiA-Daloo £&rlj IgnlUon ajmi«iDS. . . .374-376 MB-IHixso Modern Xgnltioa, itAitlD^
•ml li&gHtUig Bj&tmaxE 379-396
mO-Gt^ Twts And AdJovtlnAKiti of
IMIOO Mytt/ttHM , , , .397-406
tt^-Ome% TeotA iJid AdJusUotiiti of
mhm liMdiUff 8yit«u. 406^424
30— Win&g A Oar. ... ...... .42fi-429
51^ — IJfliyng a dkr .*.....,...* 460^436
Xovtnietloa
32 — itorago BattKtn . _ .439-466
S2A-moTl«e Ban«r7 E«palj^^. .46#47SS64S 33— Elaetnc mnd 0afl^Bl#ctric 7«Atidai 476-464
OPEBAXIOir, QMMR, BTO. 34 — Operatljif a Ou .............. .486n600
36 — Exiles of tim Boad • . . . .601-604
36 — Care of Car ...,-.,-.,,.* .606^0
37 — Accessorlee. Touring 611-620
TABLES, SPEOinCATIOKS, ETC.
38 — Insoraiico. Lk«nse and I^awt 521-626
39 — TIte Aatomoblle Saleeman. 629^^33
^>— BoiBi Power Xablea and CHneiral DatA. Standard Adju^tiiieELtA of Leading Cars. Sp^cHlcaMooi of ^f*M1ng Cars _
41 — Tlrea. Air Foinpe and €ompc««eorB.54fr-G64 42— Tire EepairEng and Care of .666^976
TEOUBLES AKP BSMEDIBfl. 46^-Dlgeet of Trouble* _ .676-661
BEPAIRINQ AND ABJUSTIKO.
44 — Tile Automobile Eopainnan ...... B(Pt fSOt
45 — Gara^o and Sliop Bquipmenta. . . .596-619
46— Bep^ring and Adjufitlng Emglnee. 620-609 iSA-AdJniftliig dutcbee, TranAmlHloii%
Boar Axles and DUf erentlaLi 660-679
46B-AdjU9tliig Wbeela, Brakes and
Steering _ , .680-694
46C-1IOW to Vm Tools and Make B«-
paliB. Oxj-Acetyletno WeldJng. . . .696-729 46D-1Tft^al Sbop Hints and Bo'rlcia. .730-744
MISCBLLAKBOU&
47^ — Commercial Cars 746-781
46 — Tbo Tractor , 763-764
49 — Engines; different prindplat 750*76A
49A- Addenda; Tractors, Truck Engines and E^pair^; OoTemors^ Motor-
c^rclee, Eepalxlng Tops, etc 829-649
BO^Dlddonary of Automobile Term*. .861 864
SnpPLEMEKTa
Tbo Ford ......,,. 766-628-864A
Tbo Packard— "3-25' ' ft "S46". .., .860-661)
Airplanes 900-928
Wiring Diagrams . . 923-921
K. W. Magneto Supplement. ........ .928-030
ladM ............................. .867-891
Liberty Engine Supplement. . . . . .933-940
INSEBTa Tlitre are serireral Inserta dealing wltlii En^ glnei, Modem Cars. Dixie Magneto, Motor- crclei, 9tc. .
Use the Index- -refer to it often. Any trouble you may have, refer to indox. Stn^ 544 for SpediicationB of Tiimding Can.
m INTRODUCTORY
The Selation of the Antomobile, Trnok and Traotor.
Although this book was originally prepared to deal with the passenger car type of Automobile, the subjects of Trucks and Tractors have been added and right at the beginning, it is the purpose of this introductory, to point out to the reader the close relation of the Automobile, Truck and Tractor, so that when the study of the book is completed he will clearly understand the differ- ence in construction.
In addition to the Truck and Tractor subject, the Airplane and Airplane Engine is also dealt with.
The same underlying principles of the Drive System of an Automobile are used in the Truck and Tractor, but of slightly different construction.
The same underlying principles of the Automobile Engine are used in the Truck, Tractor and Airplane Engines, but of slightly different construction. With this in mind, it will be easier for the student to understand the differ- ences as he progresses.
Why the Instructions Begin With an Early Type of Oar.
In order that the reader may clearly understand the details of the modem automobile and its parts, it was necessary to illustrate and describe the early type of cars and gradually work up to the more modem tjrpe. For this rea- son many of the subjects begin with early models or types, which is absolutely necessary before the reader can properly master the subject.
The reader will learn the principles of construction of the different parts of all automobiles in general use. The constraction may vary, but the under- lying principles remain the same. Consequently when the reader masters the principles involved, he masters the construction of all types of automobiles, engines, ignition systems, carburetors, etc.
The illustrations are not drawn to scale, in fact, the majority of the illus- trations are exaggerated in a great many instances — in order to clearly de- scribe the subject treated.
The writer makes no attempt to treat the subject in a theoretical man- ner, his idea being to adhere strictly to the practical side of the subject.
For many of the illustrations and much information to be found in this book, the writer ia indebted to th« *' Automobile, " of New York, *' Motor Age'* of Chicago, '* Auto- mobile Dealer and Repairer,'* of New York, and *' Motor WorW of New York, as well ai a great number of manufacturers of automobiles and accessories.
A Hodern Track,
Tho prlndpl^ of the txnck ie nmiiiir to tbe [iriticiplo of a passf^Bger car type auto- ntobilc.
Th.9 englDfi iv usuaUj" a four cyUadar tjrpe of engiue^ for roasoPH explalaed on page 747* Bee aliO] ptig® 71, Tbo truck en^i^e is a slower speed engine tkaia the autom<H bil@ engino. The avorago maximum speed of a truck ongioe is 900 to 1000 r.p. m. The sngi&e speed is controlled b^ a hand throttle aaU foot acccjlerator, the same as the auto- tnobUe engine, Uut a govtrnor la employed, far reasons statod on page SSS, wbieli is to prevent undue '* racing'* of engine when changing geara or releasing clutch.
Bit gOTttmlng tbe engine spaad, tbe car sp^ed Is alao limited* for mstapce^ the gov^ ernor can bo sot to govt^rn tlie engine speed at 960 r. p> m. wblch gives a maximum car speed of II m. p. bi, whkb is the average speed of a heavf dutj truek.
The 8p««d of a paaitng ST tyft aulomoliild varies from 1% ni. p* h. to 60 or 60 m, p, h. and a governor is not employed. The ongine •peed of a pasneiii^er lyim automobile varies from ISO r. p. m. to as hlgli as 2600 to 3000 r . p. m , The trucks however, being d es Ig a ed for coiumcretil use must neccsitarity be more efficient, hence the empluymt^nt of s goveroor.
All oompllcattd devices are ellmlnatad on a tmck, tor thf sako of afflelaiiay* For In* slaneoi the electric iilarting motor is seldom used, iustoad, the engine is aratik«d bf liaiid In connect ion ivitb an ** impulse starter" (sea page 747 and S33). Instead of a coll, batter/p generator, cut oat» timer and dis- tributor being used far Ignition, a high tension mngneto is nsuaUjf emptojred. The
gravity fuel feed system is naed instead of vacuum or pressure feed. The tubular typi radiator (page 190), for cooUng ia used in- steafl of the cellular type. The cellular type, as generally used oo automobiles, Is mors artistic in appearance, but the tubular typfl has larger openings and is less liable to clog and easier to repair.
i,*.??r71ffh*???. I* usuilljf by 1 propeller ih«ri eom WGrm geATi\\U] on aiJT«^r,.mifl|. The worm gw fJTBi ft gTtmUT reduction sDd ii itteot mud tni-
B«r szlB if uiuallr a fall flontiiiff ' 'Uvb' ' »1i (F). 8f« ^so, p«irfi 761.
iti4 reT#ri«. ud Is ftitnilmr to aa ftiUomobile tmni' iniRsioii, ^ut of hs-ftviflr tonptnictttm. Q*»r ralles' Oq ftboTA truck {Waster. modvU M & O) flfM ffjeed, rtjar whe^Ia niftke \ rtvcilutioQ to sv«i-y 24
WgCjlil 1 tl r^'"*' '*™^ ^^' ^ **> ^^■*'
ttpU di.« t^pe. Tb* clutch .Cw* a7p^«„*%?^ta siienaiTBly titsd ii la alao the coa« typS clutch.
front: ie-i7- r#.r. Tbe '^duar" loHd tir*, *|i
tha ■ pn«i«atie eerd'' truek tire, pw- pat? si*
afa alio attsaslT*!; at«d. '^ ■ ^""' SlaaHei t« the Hoaa, pag* 69 o,
clfls ef lb» paaiwi,^ car trpa of aatomobUa
Ptan witw ttf Cmat J7-2S trveiar ttn'ming t^gout ttf trantmtniom Aii4 4nvt
The Modern Tractor,
The purpose of a tractor is explained on pifei 753 and 831. Note that in addi- tion to doing tractor work« such as pulling plows or other drawbar wurk, it is also |K>»ib]e to do belt wor^ auch aa operating threshing machines, etc.
Tlie above iUustratlon Is that of a four- eiUnder engine tractor* Most all tractor •Bgiaes are four-cylinder^ for reasons ex- pUiDed on page 831.
Tbe construction of a tractor dlifers con- Uderably from that of an automobile or tnudt, but the same underlying principles of eigiae and drive system are employed.
the engine used on a tractor is a slow •P^ engine, and usually a large bore. This pwtieuJar tractor engine has a bore of 4% in. and 6 in, stroke. A governor is employed ^6r the purpose as explained on page 839. Tht ij»6ed of engine is governed to 900 r.p.m*
Tbc Ignition is usually a high tension mag- wta with an *• impulse starter*' (see page 112 for explanation of an impulse starter), ^oit tractor engines use magneto ignition r<>r reasons stated on page 831.
The tractor engine operates for long Modi of time at full power, therefore must ^ built heavier and more Bubstnotial than lit* automobile engine, for instance in the l>«tfiEgs, etc.
Fuel IT* usually gasoline to start with and Woiene to run on, after engine has started tsd became thoroughly heated. The lieatlng of a tractor engine, in order to use kerosene ar low grade fuels is a very important fac-
tor—see pages 827, 828, 831 and 71.
Drive system. The engine on above trac- tor is a four cylinder, vertical type, mounted transveraely on the frame. The power from crank ahaft is transmitted to the spur gear transmission by means of a clutch. From transmission^ power is transmitted to the rear axle by means of a spur gear drive. The differential is employed as shown in illustration. Power is transmitted to both rear wheels^ which are 62 inches In diameter and have a 12 inch face.
Speed of an average tractor is 2 miles per hour on slowest speed and 2% m. p, L. on high speed — see also, page 830.
The belt power is obtained from a 16 inch pulley mounted on an extennion of the engine shaft, and therefore runs at engine speed — 900 r. p. m.
The above tractor (the Case 15—27 h. p. tractor) has a wheel base of 76H i*»M ^^^ its overall dimensions are: Length, 126 in.; width, 72 in.; height (without exhaust pipe), 68 in. The shipping weight is 5500 lbs.
Tb© tractor puUs three 14-in. plows m tough sod or four plows under usual CDiirli- tions. It ie also adapted for other drawbar work (see page 752), requiring a similar amount of power, and it will operate either a 20x36 or 26x46 in. thresher (belt work).
It will be observed that the tractor, while It dlfrers widely in construction, from that of the truck or passenger car automobile, it is, in many respects simUar in principle, the main dllterence being in the drive system and fuel used by the engine.
ASSEMBLY OF CAR.
RUNNING QEAB.
Front Axle 1
Steering Knuckle Pivot 2
Steering Knuckle Arm (right) 3
Steering Knuckle Arm (left) 4
Steering Knuckle Tie Bod 6
Steering Gear Drag Link 6
Steering Knuckle Gear Bod Arm 7
Bmut Azla (Housing) 8
Differential (inside of case) 9
Axle Drive Bevel Gear 10
Axle Drive Bevel Pinion 11
Axle Drive Pinion Shaft 12
Axle shafts are inside of axle housing.
Brakes on Hub of Wheels ('Operated
by Hand Lever) 13
•Brake on Drive Shaft ('Operated by
Foot Pedal) 14
Brake Bods 15
Brake Pedal (Bunning) 16
Brake Lever *. 17
i^Eingi 18
%>ring Blocks or Seats 19
luring Clips 20
Frame.
ICain Frame 21
8nb-frame 22
BODY
Body 23
Fenders 25
Banning Boards 26
Dash 28
TBAN8MIS8ION SYSTEM.
I
l«wa bnk«
POWEB PLANT. Engine.
(Four Cylinder) Cylinders Cast in
Pairs 39
Inlet Valve Caps 40
Exhaust Valve Caps 41
Crank Case (Split type) 42
Starting Crank 43
Flywheel 44
Inlet Manifold 45
Exhaust Manifold 46
Exhaust Pipe 47
Muffler 48
Cooling System.
Pump 49
Badiator 50
Cooling Water Inlet and Outlet 51
Fan 52
Fan Belt 82
Ignition System.
Magneto (High Tension type) 53
Magneto Drive Gear in Engine Gear
Case 54
Ignition Switch 55
Spark Plugs 56
Cables (High Tension Ignition) 57
Fuel System.
Fuel Tank 68
Inlet Manifold 46
Carburetor 60
Throttle on Carburetor 61
Fuel or Gasoline Pipe 62
OONTBOL SYSTEM.
Steering Post Assembly.
Steering Column Tube 63
Steering Gear Case 81
Steering Wheel 64
Steering Gear Arm 65
Spark Hand Lever 67
Steering Gear Connecting Bod 6
Throttle Hand Lever 68
Spark and Throttle Sector 70
Spark and Throttle Control Bod 71
Throttle Lever Shift Hod 72
Hand Lever Assembly.
Gear Shift Lever 73
Brake Lever 17
Gear Shift Gate or Selector 76
Gear Shift Lever Shaft 77
Pedal Assembly.
Clutch Pedal 33
Brake Pedal 16
Clutch and Brake Pedal Shafts 78
Clutch Belease Fork 80
praetiet ii to hfty« Hand Xiever operate the eztemal brakes and Foot Lever the In- — both on rear wheels.
Gear Box or Goar Set 29
Cover Plate for Transmission 30
CbitclL
(Cone Typ«) 31
Clutch luring 32
ClQteli Pedal 33
Driven
Universal Joint (forward) 34
Universal Joint (rear) 36
Drive or PropeUer Shaft 36
Drive Pinion Shaft 12
Differential Driving Pinion 11
Differential Driving Gear 10
Torqne Bod 37
HO. a— Key to Motor Oar Parts; illustrated in Charts 1, 3, 4, 5, 6, 7, 8, 9, 10. 81 and 32.
i: Modam type of can will be shown further on in thif ^ook. R/ad hiding top of pafe lY.
DYKE'S INSTEUCTION NUMBER ONE.
ASSEMBLY OP CAB.
DYKE'S INSTRUCTION NUMBER ONE.
ASSEMBLY OF CAR.
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DYKE'S INSTRUCTION NUMBER ONE.
ASSEMBLY OF CAR.
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10 DYKE'S INSTRUCTION NUMBER ONE.
INSTRUCTION No. 1.
THE AUTOMOBILE: Assembly of the Automobile. Fiinctions of the Principal Parts.
The Kinds of Motor Cars. There are three different kinds of motor cars; first, the gasoline motoi car; secondly, the steam car; thirdly, the electric car.
The gasoline motor car is by far the most popular, and it is with this thai we are mainly going to deal.
The steam car, silent, smooth and easy on tires, is comparatively seldom seen.
The electric car, almost invariably in the form of a brougham or coupe, is heavily handicapped by being unable to run for more than a few hours without a fresh charge of electricity from its headquarters, and is quite in the minority. Our attention will be devoted to the car with the gasoline engine for the motive power.
The Component Parts of a Motor Car.
A car may be made up as a whole of two distinct parts, the body and chassis.
The body, which is the work of the body builder, which has been brought by him to a wonderful pitch of perfection, hardly concerns us so we will un- screw the half dozen or so bolts that secure it to the frame of the chassis and stand it to one side, for the present at least — so that we can examine the chassis underneath.
The chassis is the entire car with the exception of the body (see chart 8)'. The chassis, for our purpose, must also be divided into its main parts as follows: the running gear, power plant, transmission system, control system, equipment and accessories.
The running gear consists of parts as follows: front and rear axles, wheels, springs, frame.
The power plant consists of parts as follows : motor with its fuel system, carburetion system, ignition system, cooling system and lubrication system.
The transmission system consists of parts as follows : clutch, change speed gears, drive shaft with its universal joints and differential.
The control system consists of parts as follows : steering device, throttle and spark control, kand levers, foot pedals and brake system.
The necessary equipment consists of such parts as fenders, running boards, hood, dash, tires, lighting system, self starter, horn, etc.
The desirable equipment or accessories are such parts as speedometer,
windshield, warning signal, shock absorbers, etc.
The construction of the parts of a motor car may vary, but their purpose is the same. While it is true there are hundreds of different firms making automobiles, they all employ in the construction of their cars the parts en- umerated under the various headings. For instance, one manufacturer may suspend the power plant on the main frame, others use a sub-frame. Some use a clutch of the cone type, others use a clutch of the multiple disc type — ^but they all use frames and they all use clutches. Further on we will explain the different constructions involved in these parts, but bear in mind the principle or purpose of each part does not change.
ASSEMBLY OF CAR. 11
As we progress the reader will gain an idea of the different constructions of the component parts now in general use — for instance, there are two kinds of front axles in general use; the tubular type and the solid type. There are two types of construction of rear axles in general use; the live axle which revolves and is driven by a bevel gear and pinion, and the dead axle which does not revolve, but the wheels are driven by chain and sprocket, and so on, throughout the whole construction of a car.
*It is now clear that if the reader masters the principle and purpose of these parts then it will be no difficult matter to understand the variation in construction, and when he will have completed the study of this construction he will have gained sufficient knowledge to enable him to understand the con- struction of all cars.
Purpose of the Parts of the Running Gtear — see chart 4. The front wheek run free on the axle, and guide the car. They are called the guiding wheels and are moved from side to side by means of a steering device (63-64-65) and the direction of the car is controlled in this manner. The rear wheels are revolved by the engine and drive the car.
The front axle is fitted with steering knuckles (3 and 4) on which the guiding wheels run. These steering knuckles are moved by means of the rod (6), which connects to the steering device (65). The front axle is fitted with spring blocks (19) and spring clips (20) which hold the springs in place.
The rear axle revolves. The housing over axle is fitted with spring blocks and clips similar to the front axle.
The springs act as a cushion and protect the machinery and the occupants of the car from undue vibration and shock. They also hold the frame.
The frame of an automobile is made of pressed steel and is the founda- tion which supports the power plant, change gears, levers, steering device, fuel tank, body, etc. Each part is bolted to frame and is kept in proper relation to each other. The frame is usually hung, with the springs rest- ^ ing on the axles as shown in upper
Fir. 1. In the upper illustration is ghown the iHuStratioU, fig. 1, tO the left, Callcd
•nratang spring suspension which is used on the OVerslunCf. SomctimCS the SprinflTS
■siority of the cars today. Note that here both r^ji-i xi. -i n-i
front and rear sprincs and also the frame are above are laStenCCl belOW the axlCS, Called
the axles. la the lower illustration is shown the fU^ iinHprflliiTiir pnnGfi*ii/>finn
■adenlnng. a form of spring suspension in which ^"® UnuerSlUng COnStrUCtlOU.
tbe frame is above the axles, but the springs below a i^ ^ ^- i -i
-teidom used. A suD-framo IS somctimcs placed
A popular spring system is the cantilever, see insidc of the main frame tO SUppOrt
the power and drive plant.
The steering device (63-64-65) is usually attached to the frame. By turn- ing, the wheel (64) the car is guided through the control of the direction of the front wheels.
Brakes (13) are fitted to motor cars for stopping or slowing down and ^ usually fitted to a drum on the hubs of the rear wheels.
Purpose of the Parts of the Power Plant — see chart 5.
The engine furnishes the power that drives the car. It is usually located ^the front part of the frame, if it is a multiple cylinder vertical type of engine.
^SHKpension: multiple cylinder engines usually have four, six, eight or twelve cylinders. If it is a single cylinder engine, it is usually hung as shown
*8«e index for advantages of "three point suspension."
*Th« tjpe of clateh, axle, engine, etc. which are used on leading cars given under "Spceificatioas « Uadiag Oart*' — page 542.
=^^
12 DYKE'S INSTRUCTION NUMBER ONE.
in chart 11, fig. 1 ; if double cylinder opposed type, it is usually placed across the frame. If a multiple cylinder, "single unit power plant" (see page 85), it is usually suspended at three points as per page 786, fig. 49. This is called "three point suspension."
The carburetor mixes air with gasoline, and is connected direct to intake pipe on engine. The carburetor is connected to the feed pipe (62) from the gasoline tank.
The gasoline tank is usually placed under the seat or at the rear of the car and gasoline is fed to the carburetor through a small pipe (62) (chart 8) or by the vacuum system (see carburetion instruction).
The exhaust pipe (47) connects to the exhaust manifold and runs to muf- fler (48), which is usually placed at rear of car. The exhaust pipe permits the burnt gases to escape. The muffler placed at the extreme end of the exhaust pipe, silences or muflfles the noises from the explosions in engine cylinders.
The ignition system is a part of the electric plant; either a storage bat- tery and coil, dry cells and coil, generator, or a magneto. The coil and battery* electric system was formerly placed on the dash, while the magneto or genera- tor is placed on the engine and is run by the cam shaft or crank shaft, through the medium of silent chains. The modern coil and battery system with a timer and distributor is now placed on the engine, see Delco and Atwater-Kent systems.
The cooling system consists of the radiator (50), water pipes (51) and circulating pump. The object of the cooling system is to keep the engine from getting too hot when the explosions take place inside of the cylinders.
The lubrication system of the engine is for the purpose of keeping the bearings and rings and other moving parts from wearing. This subject as well as all other subjects will be treated separately further on.
Transmission of Power— see charts 6, 7.
The transmission or the speed change gears is that part which transmits the power from the engine to the driving wheels through a system of speed change gears (29).
A clutch (31) is placed between the engine and transmission; this permits the engine to run free, or when ** thrown in" connects the engine to the change speed gears and drive the car. The clutch is operated by a foot pedal (33) and is thrown in or out by the driver.
In a locomotive, the piston rods are connected direct with the wheels, through the medium of the cross head, and connecting rods so that when steam is applied the locomotive moves. In an automobile, the engine may be disconnected from the transmission by means of the clutch, so that the motion of the transmission or of the entire car may be stopped without stopping the engine.
Change gear principle: When a bicyclist wants to race on a level track he gears his wheel up high, so that one revolution of the crank takes him the greatest possible distance. Yet if he takes this wheel on the road and en- counters a hill, he must get oflE and walk or exert an extra lot of power — ^he needs a wheel geared lower.
In the same way, when an engine is required to do more than ordinary work, as climbing a hill, the transmission or change speed gear contains from two to four changes of gears and helps out the engine by changing to the gear ratio required for less motive power. It allows the car to move at various speeds while the speed of the engine is unchanged.
When in low gear, the engine makes quite a number of revolutions (15 or 20), while the wheels revolve once which makes the auto move forward slowly, but with considerable force, so that it can go up a steep hill or through sand or mud.
ASSEMBLY OF CAR. 13
When in second or intermediate gear, the engine makes from (8 to 12) revolutions to one revolution of the wheels, which moves the car faster than the low or first change of gears but with less force.
When in third or high gear the engine makes from (2 to 4) revolutions to one revolution of the wheels, which gives the car high speed over good roads.
If the car was going up a steep grade while on high gear, the work would be more than the engine could do, and it would stop unless one of the lower speeds were shifted in. There would be considerably more pull on the wheels.
The operation of the change of gears is by means of a side or center lever (73, chart 1, also see chart 23) ; change of gears can be made instantly. The transmission also contains a set of reverse gears, which when thrown in, will reverse the motion of the car without reversing the motion of the engine.
The transmission may be connected so that it drives the wheels by the following methods.
First — ^by a driving shaft (see chart 11, fig. 1, c and e, also (36) chart 6), connected to the rear axle, which it revolves by means of bevel gears, the wheels and axle turning together. This axle revolves and is called a "live" axle.
Second — by a single chain (see h, chart 11) connected to the rear axle, wheels and axle turning together.
Third — ^by two chains (see b, chart 11), one connected to each rear wheel, which run free on the axle, like a buggy and is called a "dead" axle because it does not revolve.
The Drive System — see chart 6.
The connection between the engine and the w^heels is called the drive system.
The drive shaft connects with the end of the transmission shaft by means of a universal joint, it has also a universal joint at rear end connecting with the differential drive pinion shaft. •
The universal joints (34-35) permit the parts mounted on the rear axle to move up and down, thus preventing the movement of the axle from interfer- ing with the drive of the car.
The torque rod (37) is usually placed between the housing on rear axle and the transmission case. The object of the torque rod (or torque arm as it is now called) is to prevent the axle housing from twisting when the power or brakes are applied (see page 22).
The drive pinion shaft (12) connects to the rear universal joint (35) and drives the bevel gear (10), which is connected to the differential (9), (see chart 5).
The front wheels on an automobile run free on the axle. For this rea- son the outside wheel is able to revolve faster than the inside wheel when the ear is turning a comer.
When a vehicle turns a corner, the outside wheels revolve faster than the inside wheels, because they travel a longer distance.
The wheels in rear must do the same thing ; if they were forced to revolve at the same speed, one would slide because it could not keep pace with the other.
When they run free on the axle, they would take care of this them- selves, but as both are driven by the engine, the transmission or rear axle is fitted with a differential, or at times erroneously called a compensating gear (see chart 18), This device is automatic, and permits the wheels to revolve at variable speeds, although both are driven by the angine.
14
DYKE'S INSTRUCTION NUMBER ONE.
Power PUnt Drive Shaft ,
;&
Universal Joint
Transmission
DriTo Shaft
Engine
Clutch
Fig. 1 — ^Methods of Power Transmission to Bear Axle, h — Single chain drive (obsolete), b— Double chain drive (used principally on trucks). ^- Shaft drire with a double opposed type of engine (shaft drive is extensively used, but the opposed type engine is seldom used), a — Shaft drive with a four, six, eight or twelve cylinder angina (extensively used).
Fig. 2 — Top Tlew of a doable chain driven truck. Rear axle is called the "dead** type because it does not revolve. Formerly employed by the Packard Motor Oar Oo.
Fig. 8 — Side view of a modem Packard chainless truck. Drive; worm: power: four eylinder gasoline engine; clutch; disk: transmisBion ; four speed selective sliding: "live" rear axle; full floating.
Worm gear drive. This system is used on a large number of cars now, especially on tmcka, and is coming more into favor every year. There is no diflterence in the transmission system, OKeept aa regards the drive, as compared with the usual bevel-gear system. In principle the worm drhre is a simple arrangement; the usual bevel gear and pinion are replaced by a specially-shaped hoUvw helical toothed gearwheel and worm. A "live" rear axle is used.
NO. 11— MatliodB of Trangmlwilon of Power to Bear Axle and Bead Whetls.
ASSEMBLY OF CAR. 16
Body.
The automobile frame, with all parts of the running gear, the transmiB- non, engine and other parts of the mechanism, when it is wifhont the bodj 11 ealled the chasds. Different types of bodies may be attached to a chastii, ind are generally fastened down with bolts.
The bodies of pleasure automobiles are classed as follows :
Boadster — ^An open ear seating two or three. It may have additional seats on rmn- niig-boards or in rear deek.
Ooapelet— 9eats two or three. It has a folding top and full-height doors with diaap- ptiring panels of glass.
Coupe— An inside operated, enclosed car seating two or three. A fourth seat facing btekward is sometimes added.
Oomrwrtlbla Oonpe — ^A roadster provided with a detachable coupe top.
Cnowr I«eaf — ^An open car seating three or four. The rear seat is dose to the divided front seat and entrance is only through doors in front of the front seat.
Tonztng Oar — ^An open car seating four or more with direct entrance to tonnean.
Btlon Touring Oar — ^A touring car with passage between front seats, with or without nptrate entrance to front seats.
Oonvertible Tooilng Car — A touring car with folding top and disappearing or remov- iUe glass sides.
Sedan — A dosed car seating four or more all in one compartment.
OUiYartible Sedan — A salon touring car provided with a detachable sedan top.
Open Sedan — ^A sedan so constructed that the sides can be removed or stowed so.as to leave the space entirely clear from the glass front to the back.
Umonslne — A closed car seating three to five inside, with driver's seat ontdde, cov- •red with a roof.
Open Idmonsine — A touring car with permanent standing top and disappearing or naovable glass sides.
Barllne— A limousine having the driver's seat entirely indosed.
Brongham — ^A limousine with no roof over the driver's seat.
Landanlet — A closed car with folding top, seats for three or more inside, and driver's Mtt outside.
Body equipment consists of a hood or bonnet over the engine which con- nects with the dash of the body. Fenders or mud guards are usually attached independent of the body, also the running board. Wind shields are placed in front on the dash. Steel pans, which extend under the mechanism, protect- ing it from mud and dust.
Commercial vehicles are those used for business purposes such as taxi- cabs, delivery and trucks.
Wheels.
Tires made of rubber are fitted to the wheels to take up the vibrations that are too sudden for the springs to absorb.
The wheels of an automobile are smaller in diameter
than horse drawn vehicles, due principally to the fact that at the high speed the automobile travels, the wheels would have to be built entirely too heavy to sustain the strain. Automobile wheels must be very strong, because of the weight that they must support, and the strain that they are under. They are made of wood or wire (see illustration).
Wooden wheels are made with a wood felloe, over which fits a steel rim that holds the tire. It is called an artillery type wheel.
Wire wheels are light, easily repaired and are becom- ing very popular.
Mud guards or fenders are always fitted over the wheels, to protect the ear and occupants from the mud thrown by the wheels.
DYKE'S INSTRUCTION NUMBEB ONE.
AttJiongli Itacn KM muij tiwelal nukM of bodi«i whicb «rs i^ivcd irpecial natDPR, th*? aiit
will fi^e thfl reader lbs nmmet of the atmndBrd tjF|ie of bod Leo,
If^« tb« Oyelt OftT U tiow c&ILcil ii Lilgbt 0»r.
TtiB Sftdui dif7i;ri from the Llmouaioe ia tli*| th« dHirei-*ft t^nt Id tKe Sed«.iEi is plactid in itftta and would b« termed a family ear, Tb9 owner quile oHcn drl^ei thii typr of car.
Til* liiancmiilM front a»»i la paTtltion««l off from arata In iht rear and is uNuaUy ebatiJfeur.
TIm Town C«f i« • lifbi, low, tKoH wbe«l bue, witb chaaff^ur'i seat in front. Thia I lued for T^ilejab iarvica.
¥b« liftndma la m trpe of e*r itasfUr to tb« Litnouiioe, but tbe r«ai- pari of top can
Tb« dlMtBeUon b«tw«ta tlM ]>«UvaEf wicoo a&d TrndG ia io aiifs and weight. Th« ia tisualb a shaft drlT«o ]>nemii«tl« tired car, whoreaa tbe truek is a double ftiain or nUaft di bea^y m*chLtie. ^
OHABT NO. 13— T7P«i of Bodies.
CLUTCfl «1A]I
Buick Six.
Tlie Bulck 1918 line vr^v compoitd of thre© modelft. Two sixot. Th« only mAterial difrereoce wat in tht wheel ba«fl, 11 B" snd 124* — ^tha ea- fcine being the tame.
The 1920 Buick ILm is comp«ied of iix models of cArs: Model K-eiz- 44, a lhree-pa»«enger roftdeter; model: K »ix-45. a fivepasftenger touring c»r; K-aiX'46, a touriog coupe; Kffix-47, . a fiv^e-pasiengcr tourio^ sedao; K-tix- 49, tt «ev«a-pasaeDger toaring car; K- Rix'50, a aeven-peascDger sedao.
Eagl&i oo All model! ia the same tlx cylinder type with valvea-io-tb^-bead.j :i%" bore by 4^" itroke. aemi-itMr bloc casiiugB. YaUfss are moaDled ia cageA — ai'e page lOP. 50 actual brak*- horao • [iower. Oooliog, ceatrifugal < pamp and cellular type radiator; ' lubrication, circubtlog epiaali ofier* Aledi by gear pump driven by tiiiral, gearB from cam ehaft; cvboretor ii the Xtarvel ihown on pai^e 179, witk rarnnm fuel fv^(\ Ryitetn explained ofi page 105; ignittoo, high tension Jump apark system — Delco electric ayttcmi Detuo Hinglft wire. Clutch* multiple dise, dry plate: transmUslon, 3 8p«ed nnd reverse. 8.36. 1.76 and 1 to 1 os firsts second and third fe&rs, and 411 to 1 on reverse, nf^lActive typtr lea page 497 for guar uliifti rear Kd«. ftiU^ floatinir type with 4 to 1. ratio oa 11B'| wheel bane and 4.<S15 to 1 on the 114* whoel bftBP car — see page 557 for typ« of rim used.
ASSEMBLY OF CAR. 17
Lights.
Automobiles are required to carry two lights in front, and another, called the tail light, in the rear. The rear light is required for the benefit of the Fire Department — to avoid accidents of rear end collision. To make driving at night safe, there are usually head lights which bum acetylene gas or elec- tricity.
Electric lights are the most popular ; a storage battery supplies the elec- tric current; when the battery runs down it is recharged from an outside source, but if car is equipped with an electric generator, run from engine, the battery is kept charged by the generator. (This subject treated fur- ther on).
Accessories.
Speedometers show the speed in miles per hour, and are operated by flexible shaft driven from the front wheel or transmission shaft.
Odometers show the number of miles traveled, either on one trip or dur- ing the entire season. Speedometers and odometers are often built in one case, for the sake of compactness, one cable driving both.
Orademeters show the per cent of grade the car is climbing.
The horn for automobiles is sounded by pressing a rubber bulb, and the tube from the bulb to the horn is long enough to have the former at the drtver's seat, and the latter well forward. Another form of alarm is blown by the pressure of the exhaust from the engine, and it is sounded by pressing ®^ a foot pedal. Exhaust whistles are the name of these horns, and the sound is very much like a locomotive whistle.
The electric horn is the most popular. It will be explained farther on.
Bumpers are placed in front of the car and sometimes in the rear. They Protect the radiator and lamps and are well worth the investment (see fig. 10 Page 26).
Wheel Base, Tread.
The wheel base of an automobile is the distance (in inches) between the '"^^^ axles and the front axles. The long wheel base rides easier than a short ^'^^el base. The frame must be sufficiently stiflf, however, to prevent sagging '^oxxx the weight on same. The wheel bases vary from 80 inches on runabouts, to I44 inches on larger cars.
The tread (also called track) is the distance the two wheels are apart ?^^*^iired parallel with the axle. The standard tread is 56 inches, measured ironx center to center.
The treads of wagons and carriages vary in different parts of the country. ^ ^He Southern states it is 60 inches, in the West 48, and most of the other parts of the country 56 inches. Small, light cars are sometimes made with a ^^^ller tread than 56 inches, but it is exceptional.
The clearance is the distance from the lowest point of the car to the road. *^^^ rough roads, a greater clearance is required than for smooth roads, as ft high place in the road would strike parts of the machinery that hung too low. The front axle, which is solid and heavy, is usually curved down in the
c^ttter, so that it will be the first part of the car to strike a high place, thereby
protecting the delicate parts behind it.
I
18 DYKE'S INSTRUCTION NUMBER TWO.
INSTRUCTION No. 2.
DRIVE: Chain: Propeller or Shaft Drive. Worm Gear Drive. Radius Rods. Torsion Rods. Drive Reduction.
The power from the engine is transmitted through the transmission; and is applied to the propelling of the car by those parts called the drive.
There are three types of drive; one the double chain drive, requiring a dead rear axle, and the other the single chain drive (seldom used), and the shaft or propeller shaft drive, which requires a live rear axle, (see chart 13.)
♦Double Chain Drive — see chart 11.
The double chain drive is seldom used on pleasure cars, but is used quite extensively on trucks, t Trucks use chains, because trucks carry heavy loads and usually have solid dead axles.
When, as is usual in cars of this type of drive, the engine is in front, the crank shaft is parallel to the sides of the car, and therefore at right angles to the rear axle. The power developed at the crank shaft must therefore be turned at right angles in order to apply it to the wheels. (See fig. 1, chart 13.) This is done by means of bevel gears, which are in the transmission case.
The power is transmitted from the crank shaft of the engine to the square shaft of the change speed gear by gears, as explained farther on. The square shaft carries a bevel gear that meshes with another bevel gear carried on the jack shaft (see fig. 1).
The jack shaft passes across the car, running in bearings in the gear case and on the frame. It is held so rigidly that while it is free to revolve, its bevel gear is always in correct relation to the bevel gear on the square shaft of the transmission.
The jack shaft is in two sections, between the inner ends of which the dif- ferential is placed, the differential, of course, being in a housing to side of the bevel gear that drives the jack shaft.
At each end of the jack shaft, outside of the frame, is a sprocket which is in line with a corresponding sprocket on the rear wheel of that side (see fig. 2, chart 13). Over each pair of sprockets passes a chain that transmits the revolutions of the jack shaft to the wheels which run loose on the ends of the dead axle.
The chain most commonly used for automobiles is called a roller chain. It consists of side pieces in pairs, each pair being secured to the adjoining pairs by rivets passing from side to side. On these rivets are steel rollers which revolve as they touch the sprockets. These rollers fit the space between the teeth of the sprockets, and as the chain bends around the sprockets the rollers are stationary, while the rivets turn inside of them.
To give the best service, chain must run true ; that is, the sprockets over which they run must be in line, the links of the chain must fit the teeth, and the sprockets must be exactly circular. If the sprockets are out of line, the chain will be forced to bend sideways. If the links do not fit the teeth, there will be a grinding that will cause rapid wear, and there will be danger of the
*For care and adjusting of chains, see instruction on trucks; also refer to this rabjeet on doable chain drive.
tThe modem type of truck uses the worm gear drive.
DEIVE SYSTEM.
19
ehaiM jumping off. If the sprockets are not exactly circular, during one part of the revolution the chain will be slack, and during the other part will be drawn tight, stretching it.
The double chain drive has advantages on heavy cars. By its use the weight of the car is carried by a solid or ''dead" axle, which is lighter than a divided **live" axle of the same strength can be. If a solid axle is bent, it can be straightened easily, while it requires an expert mechanic to straighten a bent live axle.
The disadvantages of a double chain drive are the difficulty of properly lubricating the chains-, their rapid wear in consequence, and the liability of chains to stretch and jump off the sprockets.
The worm gear drive for trucks with substantial axles of the type are now considered superior to the double chain drive.
'live'
Single Chain Drive— see chart 11.
This type of drive is now seldom used, and was formerly used only for cars with engines of small power, in which the engine is usually horizontal,, with the crank shaft lying across the car and parallel to the rear axle.
A planetary change speed gear or transmission is usually used in a car of this type, and its sprocket is in line with the sprocket mounted on the differential on the **live'' rear axle (see chart 11 — also fig. 5, page 47).
fcnicin*
Clutch Peda]
OLUTCH
?^ ittodcm method for drlTtng the rear aade is by means of s propeller type of drive shaft with m J^^el dririog pinion and bevel driven gear on differential on rear axle. ^'Bercial cars with shaft drive instead of double chain drive often use the worm drive, see page 21.
^Propeller or Shaft Drive — see chart 11.
Xn this type, a shaft connects with the square main shaft of the differential fr^ is extended to the rear axle, where it ends with a small bevel gear called
the
^^e drive bevel pinion.
.. Ihis driving pinion meshes with a bevel gear on the differential jp*t is mounted between the inner ends of the two parts of the live rear axle, caii^^ the axle drive bevel gear.
. . ^the propeller or driving shaft, always has one, and often two, universal jomt:^ in between the gear box and drive pinion on rear end, so that the mov- ^ ^f the rear end as the axle receives the jolts of a rough road does not raefji; i^ driving.
*rhe bevel gears are contained within a casing or housing that supports ^^ bearings for the parts of the axle, and also the end of the driving shaft, «o Xhai the bevels are held in the ^ame relation to each other, regardless of the moving of the axle.
20
DYKE'S INSTRUCTION NUMBER TWO.
c
-^
ifiOmB B^
cr-Tr
c
^0cif smrr
-ff/frijr£^nu
Of/IMSS SPtltO
S£M
X
Fm^ms
Sf^stgtr
■^
Fig. 1.
cS^AS
Fiff. 2.
„ DISTANCE Off MOIU^ RODS
( )
(^^T7
S>£ms
\^^
mr
a
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fi^l^t^M
TOftS/OM /iOD
Fig. 3
CHABT NO. 13 — Explaining the Radius Bod, Torque Ann or Torsion fiod and Jack Shift
DRIVE SYSTEM.
21
The advantages of this tjrpe of drive are that all of the moving parts are enclosed and protected from dust, and run in grease or oil, which means perfect lubrication.
The disadvantages of a divided or split rear axle, are the difficulty of keeping the bevel gears in exactly the correct relation to each other, because of the bending or springing of the axle, and the troubles that may come from
the general weakness of a live axle. (This trouble has now been overcome. During the early days it was a source of bother.)
fOears.
Bevel gears must be cut more accurately, and meshed more carefully, than spur gears. They are used principally for driving the rear axle (see page 32).
To transmit power without more loss by fric- tion than can be helped, there must be as little play as possible without having the teeth bind.
tThe setting of bevel- gears requires careful ad- justment, for if incor- rectly meshed they will be noisy, and will wear rapidly.
HELICAL OR SPm^L OR ^H£W &LAfT5> NOTL aiiOViJ HOW THIS GEAR CAN St PLACED RIOHT ANGii
B£ VIL p. MOW
'VLfHT CHAIN
DOG CLUTCH
SafNTCHMN &P[^0C»^IT CHAIN
Note the different methods of driving. Bevel gears are used extensively on rear axle drive systems. Worm gears sre also used on rear axles. Helical gears, silent chains sre used extensively for magneto, electric starter and generator drives. Spur gears and the dog clutch are used in the gear box.
i^The worm drive gears are fast becoming popular for rear axle drives, especially on commercial cars (see illustration above).
The spiral bevel, which is often referred to as helical gear is similar to ^e worm. The worm gear makes a wiping contact and the helical more of a filing contact (see page 35). The **skew'' gear is the same as the helical ffear. This type gear is also used to drive ignition systems, etc.
Silent chains are used principally for driving generators, magnetos, cam ®*Jafts, etc. (see index).
Sprocket chains are used to drive the rear wheels in chain driven cars.
_ '''Radius rods: are mostly used, on commercial cars using double
^^ixi drive. They extend from a point along side of the frame in line with
**^ jack shaft, thence to rear axle. Therefore they keep' the chain at the
proj^ej. tension and the distance from sprocket to sprocket the same, no matter
^ow- rough the road. A turn buckle is provided to adjust (see fig. 2, chart 13).
^lany manufacturers however, have now discarded the radius rods entirely.
^Also called "strut** or "distance** rods.
tSee rear axles in repair subject and supplements, the "ordinary bevel" and the "spiral bevel**
. -^ TBevel gears for final drive are of two types VOt^ejj referred to as the helical).
^In principle the worm drive is a simple arrangement; the usual bevel gear and pinion are replaced "T ^ specially-shaped hollow helical-toothed gearwheel and worm, the latter engaging in the teeth of *** Gearwheel, the axles of the two shafts being at right angles. When accurately made, worm gears 'h ^^^«f **^ smoothness and silence. The worm may engage either from above or below the gear-
^^!J*l. The angle of the worm and gear may be as much as 45 degrees. Tlie worm (W) is made
at tttrd steal and the wheel (B) of bronse.
22/ DYKE'S INSTRUCTION NUMBER TWO.
The Torque Arm. A torque arm (''torque*' means turning movement or twist) is used on shaft driven cars. It extends from the cross member near the transmission to the housing on the rear axle, (construction varies).
A usual construc- tion is shown in illus- tration. Note the arm (N), extending from the rear axle housing to a spring arrange- ment or torque pillar ^^^ attached to a cross
2- ph>P7*ifrnnt^'"^^iag^^^^ll^^iHfc^^rs. // member, in line with
c. tFowu i»c.'^s ^neofcp-^ ^^^^r>""^l ^^^fetf the drive shaft (see
F DiQereiitm brvcl ^t»r pituoui. / tfS_ * ^^^■^^^^'W lllUStratlOU (S-N).
G. A*Je CA^iiig.. ^' ' ^f~^ ^ ■^*' ^ '
H. Ur^ke J.pt!ili«rj by pid^L
AI Worru vihtri boding, ft. ktii ipnoi^ th^ki^. ^r r)*! 4-1* g HotCllKlSS
N. Torque rod*. S. Torque pilUr. y" 7"^ ^ ,
drive the torque and drive is taken through the rear springs. The main leaf of each of these is made strong enough for this added duty, and the construction does away with torsion tubes, torque arms, and radius rods. On^many cars the propeller shaft housing is made very heavy and acts as the torque arm.
If it were not for the torque arm, the revolving of the bevel gears would tend to revolve the rear axle housing, instead of revolving the axle shafts alone. While the construction of the rear axle would of course prevent this, there would be considerable play in the course of time, and the driving shaft might be strained and sprung out of line. The torque receives this strain, and protects the driving shaft. In other words it resists the torque of the rear axle when power or brakes are applied (see note on page 32).
Drive Reduction.
In all but racing cars, the speed of the crank shaft is reduced so that the road wheels turn once while the crank shaft revolves from three to four or four and one-half times with the high speed gear engaged.
On cars with single chain drive, this is done by having the transmission sprocket ^maUer than the axle sprocket.
If the reduction is to be three to one, that is, if the crank shaft revolves three times to once of the axle, the axle sprocket will have three times the number of teeth that the transmission sprocket has.
On shaft driven cars, the reduction is made at the axle drive gears. The gear on the axle is given as many more teeth than the pinion on the driving shaft as is neeessary for the reduction that is required.
In the worm drive (see pages 32 and 35) the reduction is governed by the angularity of the teeth and not by the ratio. In other words the size of the worm could be ehanged Vithout its changing the speed. (The angularity of course would have to be the same in both cases.)
To make the point clear as to just how the speed reduction is brought about in the worm drive, imagine the screw thread on a vise shaft which draws the jaws together. If that thread is coarse or has only a few to the inch, the jaws would move towards eaeh other rapidly and of course would take some power to move it; if, on the other hand there were quite a number of threads to the inch the jaws would move slower but it would take less power to exert the same pressure.
The reduction on side chain cars is sometimes made at the bevel driving the jack, but usually at the sprockets.
Bacing cars, or high powered touring cars for use over good roads, apply this redue- tion for the direct drive, but by the use of gears in the transmission may bring the speed of the wheels to the speed of the crank shaft, or even more.
When the "gear ratio" of a car is spoken of, it is this reduction that is' meant. A car spoken of as having a "gear ratio of 3% to 1" is one in which the drive shaft makes 3% revolutions to one revolution of the road wheels on the high gear.
STEERING, SPRINGS AND BRAKES. 23
INSTRUCTION Na 3.
^STEERING, SPRINGS, BRAKES: Principle of Steering. Springs and Brakes.
**Steering. The principle : Pulling on one of the reins swings the horse to that side, in steering a wagon. The shaft or pole is attached to the axle, and the axle is pivoted to the king pin, all swing with the horse.
If you go straight ahead, the front and rear wheels of any vehicle move in straight lines. To make a turn to one side or the other, the front wheels are swung so that they are at an angle with the rear wheels.
Whenever the front wheels stand at an angle with the rear wheels, the vehicle will turn, and it will continue to turn until the front wheels are swung back to a straight line again.
In a horse-drawn vehicle, the front wheels are square with the axle, for wheels and axle swing together. (See fig. 1, chart 14.)
In an automobile, the front axle does not swing, but each wheel swings on a pivot at the end of the axle.
It would not be practical to steer an automobile as a horse-drawn vehicle is steered, for the axle would have to be very heavy to support the weight, and besides, it would be so hard to swing it that steering would be difficult. Another reason is that the body would have to be raised up high so the wheels could go under it in making a short turn.
A fixed front axle is always used on automobiles. The pivots on which the front wheels swing must be as close to the hubs of the wheels as possible, for the closer they are the less leverage there will be to overcome, and the easier it will be to steer, also less liable to break.
When a wagon or automobile turns a corner, it moves in the arc of a circle.
In a horse-drawn vehicle, the front axle, because it swings on the king pin, always points to the center of the circle (see fig. 1.) Notice that both wheels and the axle are perpendicular to the same radius of the circle in Sg. 1.
The front axle of an automobile is fixed and cannot turn, and therefore ^^y its pivoted ends point to the center of the circle (fig. 2.) Notice in fig. ^1 tJiat the axle does not move, but that each wheel moves.
When running straight ahead, the front wheels of an automobile are ^vi^are with the axle. When turning, the front wheels are not square with ^^ axle, but at an angle with it.
Because each wheel is square with its axle end, and both axle ends point ^ "tie center of the circle, each wheel is square, or perpendicular to, a radius ^' ^tiie circle. If both were perpendicular to the same radius, which they are ^^^, the wheels would be parallel with each other.
Thus while the front wheels of a horse-drawn vehicle are always parallel ^^ each other, the front wheels of an automobile turning a comer are not P^^^llel to each other on the same radius.
*See pages 684 to 691 for "adjusting brake" and pages 691 to 693, "adjusting steering."
«Mw. Sometimes the driver will notice he can turn his fron.t wheels farther to one side than the other.
^^^ is dne to two causes: (1) the steering knuckle arms are not properly lined up; (2) the tire
^ 'Wheel may strike the steering knuckle thrust arm.
• It is also noticeable that an automobile has a tendency to travel to the curb when running on the
**^% of atreeta. This is due to the oval surface of street or if wheels are "cambered" too much, see
**8«e also, page 601.
DYKE'S INSTRUCTION NUMBER THREE.
|
^= |
|
|
^ |
h^J |
Showing how a Front Axle of a Showing how the Front Wheels of
horse-drawn vehicle gives the direc- an automobile give the direction
tion a horse-drawn vehicle runs. the car runs.
Front Axle.
1— Front Axle
2— Steering Knuckle
3— Steering Knuckle
Ann 5—. Rod
t>— Steering Arm . Thrust Bod 7— Knuckle Thrust
Arm
Steering and Oonnec-
tions. 81~Steering Device
Housing 63— Steering Column 64— Steering Wheel 65— Steering Arm 57— Spark Lever 68— Throttle Lever 71— Spark Lever, bell crank connecting through bevel to spark lever on Wheel 72— Throttle Lever, bell crank con- nee ting with throttle lever thru a shaft, thru steering column, with t h r o 1 1 le lever. 68 W— Worm Wheel S— Sector.
Sj)ark Lever (67) connects by a rod (which runs through the hollow steering post) id operates through bevel gears the Bell Crank (71), which in turn operates the timer I the engine or contact box on magneto, and advances or retards the spark in linders of engine.
Throttle Lever (68) connects by a rod, through bevel gears, and operates the bdl ank (72). which in turn is connected by a rod with the throttle valve on the carbure- r, and controls the speed of the engine by oponing and closing a valve which Imits or cuts off the gas supply.
3ART NO. 14^Ezplanation of Steering. Steering Gear, Parts Spark and Throttle Lever System on the Steering Device.
and Oonneetlona.
STEERING, SPRINGS AND BRAKES. 20
The steering mechanism must be so arranged that the front wheels are parallel when the ear is running straight ahead, but stand at an angle with each other when turning a corner.
Each of the pivoted axle ends (2), which are called steering knuckles, has a steering arm (3 and 4) projecting from it.
The ends of these two arms are connected by a rod called a drag link or tie rod (see fig. 5). When the drag link is moved endways, both wheels move with it.
The two steering arms are not parallel, but incline a little toward each other. If they were parallel, the two wheels would be parallel, no matter how the drag link was moved. As they are not parallel, moving the drag link moves one of the wheels through a greater angle than the other, depending on the direction the drag link is moved.
The old style of steering arrangement was a lever and rod running from the driver's seat to the steering knuckle. This old style arrangement would reverse and was unreliable. In striking stones or ruts in the road the wheels could be thrown from side to side, and the driver would be obliged to grasp the steering lever firmly to keep the car straight.
A bad place in the road might throw the handle out of his hand. While this is good enough for a light slow speed runabout or electric vehicle, it would be very serious with a large, heavy automobile.
A device must be used that will swing the front wheels when the steering wheel is turned, but that will keep the front wheels steady, and prevent their moving the steering wheel.
This is called an ^irreversible steering gear, and while it is made in many ways, the chief types are the worm-and-sector, and the screw-and-nut or worm-and-nut, all shown in chart 14.
*'The worm-and-sector type consists of a worm (w), .which is attached to the lower end of the rod moved by the steering wheel (64). Meshing with the worm is a sector wheel (s), so that turning the steering wheel turns the >^onn, and moves the sector wheel.
Attached to the sector is an arm (65), which is connected to the steering knuckle by the connecting arm or rod (6). The end of arm (65) and arm (7) we ball shaped, and fit in a socket on the end of rod (6) so that the fit is always tight, whatever the angle between the arm and the connecting rod "jay be. The socket is often movable, with strong springs on each side to hold "le parts together, and to take up some of the shocks of the road.
The worm and sector are contained inside a metal case to protect them "om dust, and to hold the grease in which they are packed.
**The worm-and-nut type steering gear shown in chart 14, has a nut through which a worm passes. Instead of a ** sector" the nut is used, ^e worm is fastened to steering rod. Turning the steering wheel moves the oot up and down.
One arm of a lever fits in a groove on the outside of the nut, and the other end is connected to the steering knuckle by a connecting rod. Steering gears are usually built so that wear can be taken up.
The breaking of any part of the steering connections is more likely to cause a wreck than the breaking of any other part of the car, and must be watched carefully. The parts must be kept tight enough to prevent play, but i&ust not be so tight as to make steering hard. All parts must be kept lubri- cated, and the connecting rod, tie rod and knuckle joints are usually packed ^ grease and protected from dust by leather pockets that buckle over them.
*A Hetring gear ia smid to b« irrererslble when an ordinary road wheel impact will be insufficient ^ tarn the steering wheel. This is simply a question of reduction between the steering worm and C*ar, the greater the redaction, the less reversible the system and likewise the slower the motion af steering the road wheels in relation to the movement of the steering gear. Therefore a heavy <ar will be normally less reversible than the steering Kear on a lifhter car. **8ee also, page 691.
DYKE S INSTRUCTION NUMBER THREE.
Hajr elKpilo r«&r sprtaf «iic^or«d cfi pint oa «m
3. A
FIf. 8» A hilf-elliptic spring for front. Tig, ^. ., •prlng for th« rear. Fig, 2. Throe biilf-elliptic «prinjf very pnpuUr type of spriof for retr iUxpensioD.
Fig, 10. Bumpsra hrt pkccd on tho front and quit* oitea on th« roar of tbo car to protect the rftd]»tor iiad lamps und rear of ear. See also, puge 730, 514
yif.v
Fig. 9. Friction type of shock abaorbvr conaisti of A single arm, A. sod a doubls arm, B, ^riction- allj joined by bolt, 0, luid adjuAtlQg nut, H. Arm A works beltreen ibe two memboni of arm B. giv- ing a ttraigbt op -and- down movemont, and tbe arm A being made of tpring tteel altowa for any side- ftvfay. The arm A carries a flanged cover, D, form- ing a cup-like space on each side. lo these tnaces •re placed the friction platea, which are telf*ltibri' ealinir nnd highly impervious to wear. By screwing •nfflclcntty on adjusting out. H» any desired degree of friction may be obtained,
Adjustiseiit dial, F, and indicator, G. provide in^<..,w i.f « enuring the correct tension for the car* A pensating sprine. E, takes up any little
\i itically. keeping the friction uniform
afu . ...._ „,^justment has been made.
The arms A and B are joined to the frame and ftzla by two ffictionat joint*, vhich also can be ri rtgulated, Abo^e type I* the * 'Hartford.'* •#♦ ' page 732 for the ** Conn e<rti cut.'*
half-elliptic spring for ttie r«ar. Fig. 1, A full eUiptie I for the rear. The cantilever spring page 27 is a
Fig. 7. Atr irprlng or plunger type shock absorber consists of an air chamber made up of two lectioDa,
one of which tcteecopes into the other. The outer eeetion is attached to a bracket on the frame of the cur (A). The inn«r sec- tion is attach- ed to one end of one of the springs, (B).
The cham- ber la partly filled with oU« through the filling -plug bole unditr the cap (C). J T h e milDg- plug is flttod with an ordin- ary Schmder tire type of air valvo through whk-b the chamber may be cbarKcd with air at any desired pressure^ by means of au ordinary tire pomp.
Th« oil In the chamber seals the packings of th« teloBCopiDg joint and prevents the air from leak* ing out.
The tDftchanlsm inaldo tho chamber is a tmaU oil pump wbich is worked automatically by the up and down flow of oil past the flat piston (D). when- ever the air spring Is compress- ed or extended. A trifling amount of oil which is always passing by the packlnjirs when in motion keeps them thorough- ly lubricated The surplus drama into a collecting pocket, and the auLomatic oil pump delivers it back into the cushion chamber.
The oil passage surrounding the piston D is purposely re- st rieterl in order to retard tho quick reaction of the spring, and thus prevent the disagrea* able and dangerous catapult «£> feet that is so apt to throw paasengers from thetr seats when the car is patsing over "thank - you -mft 'ami,** ear tracks or other road obstruc- tions.
All of the time that the sprlsf
uiTiM^ Is in action, air is being drami
"**^ in through filtering matorial 1&_
B the "breather" E. and blov
out through suitable pasaag
in such a way as to keo^
telescoping joint free of dtui and dirt. (Westinghouse.)
{SImTp
OHABT NO. 15 — SprinjEB. SIiocIe Absorbers.
g^mM
STEERING, SPRINGS AND BRAKES.
27
^Springs — see chart 15.
All yehicles intended to move at more than a very slow speed must be provided with springs. Springs not only protect the occupants from the vibra- tions of a rough road, but also keep the machinery from being shaken to pieces.
The size and strength of the springs depend on the weight of the vehicle. Springs that are too weak will not give sufficient protection and if they are too strong they will not have enough resiliency.
Types of springs in general use are: Full elliptic, three-quarter elliptic, half elliptic and cantilever.
Tlie fuU-eUlptic was formerly used od a great many cars for the rear, as per fig. 1. In some instances it was used in front.
Other types of rear spring suspension are shown in figs. 1, 2 and 3, also the cantilever, fig. 4.
The cantilever spring system (fig. 4) is probably the most popular present day practice. The illustration shows how it compares with the ordinary half-elliptio principle shown in fig. 3.
In the cantilever spring the forward end is shackeled and the axle attached to the rear end. The center of the spring is attached to a trunion or bearing on the frame. Thus the spring has a certain amount of movement about its center. One good feature of this form of spring is that it reduces the unsprung weight of axle. The shaded parts of the respective springs show the comparative amount of unsprung weight. In the cantilever form of spring the heaviest part of it is supported by the frame.
The half-elliptic spring (upper fig. 8) is used to a great extent for the front.
^Breakage of a spring means breakage of one or more of the leaves. Breakage almost always occurs in the ex- pansion that follows a heavy compression, and not dur- ing the compression. In other wordsy it is the rebound that breaks the spring.
Because the leaves slide on each other, they wiH wear and squeak if not properly lubricated.
To lubricate between the leaves it is necessary to
relieve them of the weight they carry. This may be
done by jacking up the body, or taking the springs apart,
and spreading heavy grease or graphite on the leaves.
_- ^. ^ „4_^, This is quite a job and is seldom done (also see index
Th« thr««-qiuirter •lliptie re«r in,a.,i-«fi^^ ^Jr.^ »n
•priar A type leldom lued. ''lubricating springs.'')
Shock Absorbers — see chart 15.
Ab breakage will come during a rebound, devices called shock or jolt absorbers are attached to the springs to check their up movement, also to prevent jolting on rough roads.
There are two types of shock absorbers in general use ; the friction type and the air or plunger type.
Hm friction type is shown in fig. 9. All these movable frictional parts offer a con- •taat reoetanee to the vibration of the spring both ways, and it is easy to see that when fke wheel strikes an obstruction, the arms come together, but instead of the flying back, as does the free spring, it is retarded by the friction and moves gradually to its normal position^ since tiie frietion is always the same, while the tension of the spring diminishes as it approaches its normal poedtion. See also, page 732.
ns air or plimgsr typo is shown in fig. 7 chart 15. There are other types of plunger type shock absorbers, bat the two mentioned are most popular.
*8m rtpeir mbj^et for repairing springs.
28
DYKE'S INSTRUCTION NUMBER THREE.
/tea, mi^BLB ACrmO SAAfO
n\
^
CfiABT NO. JU — Brakes and Brake Syatema. Explanation of tha "Bunning'* or Foot Brake and
the ''Emergency" or Hind Brake. The band brake oentlly operates the internal brake InaMa af
iAe remr brake drums or the brake on trautmisaion shsft. The foot brake operates the atemml
^rsko oa Ihe outnif/e of rrar dniins. Thi* m nifuli^rn prartico.
STEERING, SPRINGS AND BRAKES. 29
^Brakes — see chart 16.
An automobile is equipped with brakes, usually on drums on the rear wheels, so that its motion may be checked or stopped when running or so that it may be held on the side of a hill.
In a horse-drawn vehicle with steel tires, the brake shoes press directly on the tires, but as this would quickly ruin rubber tires, brakes for automo- biles are of other types.
Because of the weight of an automobile, its brakes must be powerful in order that it may be stopped suddenly when necessary.
Practically all automobiles are fitted with two sets of brakes, called the running service or foot brake and the emergency or hand brake.
"""The foot brake is applied by pressing on a foot pedal (16) and is the one most in use because of its convenience, and because it is used most when ninning. The foot brake is also called the service brake.
The usual method of connecting the running, service or foot brake is by a contracting band on the outside of the brake drum on rear wheel hubs called the external contracting band brake.
The emergency or hand brake is usually applied by a lever (17) at the side (or center) of the driver's seat, so placed that he may apply his whole force to it. The emergency brake is seldom used while running. It is usually applied when the car is left standing, in order to keep the car from rolling down an incline. It connects in almost every instance with the internal ex- panding brake inside of the brake drum on rear wheel hubs, but occasionally will be found connected by a contracting band over a drum mounted on the Diain transmission shaft.
The foot brake pedal is the right pedal on most all cars, see ''operating a car."
Types of Brakes.
Therefore summing up the types of brakes we might say there are but two distinct types in general use; the external contracting and the internal expanding type.
The external band brake is a flexible steel band faced with an asbestos composition — called Raybestos or Multibestos.
Setting the brake causes friction between the brake drum and the lin- ings, hence the use of asbestos composition.
Band brakes are of two kinds: Single acting and double acting, the latter being an improvement over the former.
The single acting band brake (fig. 1, chart 16) only binds when the drum is revolving in one direction, having very little grip when the drum is re- irolving in the same direction in which the band is being pulled. This form is going out of use for automobiles, for it cannot be depended on to hold the car from running down hill backward.
The double acting band brake (fig. 2), is taking its place, for it holds with the drum revolving in either direction. In this form, both ends of the brake are attached to the lever or pedal, and so arranged that while one end is being pulled in one direction, the other end is being pulled in the opposite direction. This binds on the drum so tightly that it may be depended on to hold the car in any position.
*Th0 nmainf braks it now known ai ths "foot brake." The emergency brake U now properly criM tiie ••kAAd brake."
8m pttc* Mft for "adjnatinf of brakea."
30
DYKE'S INSTRUCTION NUMBER THREE.
The brake shoe is a band that may either be drawn around the outside of the drum, called the external band brake, or expanded within it so that it bears against the inside wall of the drum, called the internal expanding brake. Sometimes the internal brake is made of metal.
The external type of brake is usually of the double acting band brake type, and is always placed on the outside of the brake drum attached to hub of rear wheels.
The internal expanding brake acts on the inside of drum (IB, fig. 7) and may be a metal shoe or metal faced with asbestos composition, but more frequently a band faced with an asbestos friction composition.
The internal band brake formerly con- sisted of two shoes of metal, but the modem form is shown in fig. 4, chart 16. When the lever (B) is raised the wedge (C) forces the internal brake against the inside of the drum. This brake shoe is lined with Raybestos or some similar material.
A combination of internal expanding and external contracting brakes are shown in fig. 4, chart 16. Lever (A) operates the external brake and lever (B) the internal brake. (See also fig. 7 this page, and page 689).
FIG?
Fig. 7. — ^A combination of an Internal •xpandlng and external contracting brake lyitem on brake drum of rear wheel hub. OB ii the outer or external and IB is the inner or internal. B ii the hand brake rod operating the internal brake. H, foot brake rod operating external brake. Ad- Juitment of external brake is made at F. Q and 0. Adjustment of Internal or hand brake la at A. It is turned up or lowered io at to have 1-64 inch clearance between brake drum and brake. (See page 691 for * 'adjusting brakes" for further in- formation.)
Brake Connections. There are two methods usually employed for the hand brake; (1) by con- necting hand l^ver with the brake on transmission shaft; (2) by connecting with ti^e internal expanding brake inside of drums on the rear hubs. This
latter method being the one in general use. The foot brake on most all cars connects with the external band brake on rear brake drums. It is used most and requires more attention.
Brake Equalizers. When the foot brake pedal or hand brake lever is applied, the pull should be the the same on each brake on each wheel. If one brake rod is longer than the other the brake effect is not equal on both wheels, and this has a tendency to make the car skid.
To overcome this, a brake eqnaliier is used, the principle of which is shown in figs. 5 and 6, chart 16, and page 204. This is a rather crude illustration in chart 16, but it clearly explains the principle. In chart 100 the idea is more clearly explained. The brake equalizer, however, has been greatly improved as shown in illustration, fig. 8. Also page 32. In- stead of an equalizer, the rods (R) are placed in bearings and the rod (P) connects with foot brake and rod (H) with the hand brake.
If a brake squeaks, it is an indication that it is dirty and needs cleaning The dirt clogs the pores in the surface of the lining and glazes it over. Qaso- line or, better, kerosene will remove the dirt. The wheel should be removed and the linings cleaned with a stiff brush, such as a tooth or nail brush.
Fig. 8. — Note modern method of con- necting the two brakes in rear.
AXLES, DIFFERENTIAL GEARS, BEARINGS.
31
INSTRUCTION No. 4.
AXLES, DIFFERENTIAL OR COMPENSATING GEARS, BEARINGS: Front Axles. Rear Axles. The Differential: principle and application; the bevel and spur gear. Bearings: ball and roller.
Front Axles.
The front axle of a modern car carries most of the weight of the engine, and most at the same time withstand the shocks and jars that it receiveB through the steering wheels ; it must therefore be strong and stiff.
Front axles are of two ^es: tabular and solid (figs. 1 and 2). Formerly axles were made of heavy steel tabet» but steel drop forgings with a cross-see- tion of the form of the letter I, is con- sidered to give better results.
The center of the axle is usually bent down, so that it is the lowest point of the car except the wheels; this is done in order to protect the mechanism from being struck by high spots in the road. A rock or stump standing up high enough to hit the fly wheel, will first
itrike the axle, which is strong enoupch to withstand a blow that could easily
dimage the engine.
The steering spindles are that part of the front axle on which the front wiieeb revolve and are made of nickel steel, heat treated. The steering spindles are sometimes fitted with either roller or ball bearings. The steering tanudde is that part which fits into the yoke of the axle. The steering arm (66) of the device (page 24) connects with the steering knuckle thrust arm (7), and movement of steering wheel, then guides the direction of the wheels.
♦Bear Axles. There are two types of rear axles; the dead axle and the live axle.
Dead axles are stationary, with the wheels running free on the end of ^e, and are usually made as shown in fig. 3. The wheels are usually revolved l>7diain and sprocket (see charts 11 and 13), and there is no provision in axle itaeU for driving wheels.
Live rear axles is the name given to axles that revolve with the wheels, and are known as plain live axle, semi-floating axle, three-quarter floating axle, fnll-floating axle.
A live axle on any type is made in two sections, the differential be- iog placed between its inner ends, this makes it necessary to support the axle parts in a strong housing and to brace it, in order that the parts of the axle do not sag or get out of line.
The axle is contained in a housing which is a metal cover entirely sur- ronnding it; the differential gear, which is in a smaller housing of its own, being also inside of the axle housing. The housing extends to the wheels,
*B— pagM 644 to 646 for mako of axloi uiod on loading oari and pago 66f for pointen."
'roar axlo
32
DYKE'S INSTRUCTION NUMBER FOUR.
A
Eir«nul BfAkr
J a If nut
Axlf
All* Mi»Diiat
Din«r#»(ial Beirini
Constxuctlon of a Bear Azle — (Harmon). lUustrating rear axle complete with bevel driving gear (E). Differential (bevel pinion type). The actual driving axles do not support any dead weight. The road wheels run on ball bearings (I) carried on the outer sleeve or casing of the alle. The details are aa follows: — (A) propeller shaft connection. (B) driving pinion shaft. (C) ball thrust bearings. (D) bevel driving pinion. (E) large bevel. (F) differential gear. (G) half of driving axle. (H) tubular outer casing or sleeve. (I) ball bearing for wheels. (J) driving ends of axle (squared or keyed). (K) roller bearings in differential case. (L) drum of internal and external brake. (M) hub of detachable wire wheel. (N) casing enclosing bevel gear and differential.
Note — The power is transmitted from driving bevel (D) to large gear (E) — this being bolted to the case of the differential (F) — thence by the inside pinions to each half of driving axle. It Is usual to * 'anchor" the outer casing enclosing the differential gear to the chassis by means of torquo or hound rods bolted to the upper and loiwer points of the gearcase which counteract the tendeney for the whole casing to twist round from the reaction of the driving effort. On some cart the raar springs are made to serve as torque rods.
Fig. 3 — A single chain driven live rear axle now obsolete.
Fj^. 4 — Overtype wprm drjv$ rear axle with inipf^e- tloa cover plate re- nioveU eJcpo»lng the gear.
tfuLfm Mt0im
Fig. 2 — Full floating live rear axle with roller bearings.
OHABT NO. 17— Bear Axles.
AXLES, DIFFERENTIAL GEARS, BEARINGS.
88
and is enlarged at those points to take the ball or roller bearings. These bearings ran between the axle and the inner side of the housing, or as shown in figs. 5, 6 and 7.
There are also bearings at the inner ends of the two parts of the axle, close to the differential. The axle housing of this type must be heavy, as it anpports the weight of the car.
Types of Bear Axles Explained.
Plain live axles: have shafts supported directly in the bearings at center and at ends, carrying a differential and road wheels. This type is now prac- tically extinct.
*Fiill floating type of rear axle: the weight is taken from the axle, and mpported on the housing through which the axle passes (fig. ^).
The hubs of the wheels are outside of the housing, and the bearings are between the inside of the hub and the outside of the housing (fig. 5).
The axle passes through the housing, and the ends that project are square; oyer these square ends fit caps that screw or are bolted to the outside of the hub. Thus when the axle revolves, the caps transmit the movement to the wheels. As the wheels run on the housing, the housing supports the weight, the axle serving only to turn the wheels. By removing the caps, the parts of the axle may be drawn out without removing the wheels, which hold up the car whether or not the axle is in place.
By jacking up the car to take the weight from the wheels, they may be drawn off the housing. The live axle is not continuous, but is dividad in the center (see chart 18).
In the "geml-floatbi«" type, more properly called the ''fixed hub*' type (see figure 6), the driv- ing shafts turn freely within the housing. At their outer ends they are fixed in the hubs of the wheels and earry the bending stresses as weU as the torque. The hub of wheel in fig. 6 is fitted to shaft (P) with Woodruff keys and nut (N) which serve to secure wheel to shaft. Hub cap is merely a protection to end of hub.
In the "three quarter fioating" (figure 7) or better the ''fianged shaft'' type, the housing ex- tends into the hubs of the wheels as in the ''full floating" type, but the ends of the driving shafts are connected rigidly by flanges with the wheels so that the shafts take almost all the bending stresses and all the torque. In the flanged shaft axle, espe- cially when only one bearing is used under the cen- ter of the wheel, the stresses are quite similar to those in the fixed hub type.
In the "fuU floating*' type of axle (figure 5) all the bending stress due to static force and skid- ding force is carried by the housing. The driving shafts turn freely within the housing and bear only the "torque" or stress of turning the wheels. The shafts are said to float within the housing.
In the full floating axle the shafts can be more easily removed for repairs. This is an advantage. It is necessary to make the full floating somewhat heavier than the fixed hub type for the same capacity.
*8m Alto index for "axlea, full floating;" and ''removing axles." aee pages 669 and 932.
Ib th« fan flostlBf Azle the entire differential can be removed by unscrewing 4 bolts (aft«r ««vcr pUte U removed). In the % floating, two gears must be removed first, before differential •u be taken oat. and in the temi-floating. the entire housing must be removed from car, see page 669.
^
^
ric. f Ty*t-9mmUT /lMn'«( «r fUmtfJ Sk^l
86
DYKE'S INSTfiUCTION NUMBER FOUR.
^Bearings.
Every part of the car that moves with a rotary, sliding or other motion is supported in bearings, which together with proper lubrication reduce wear and friction.
There are three different types of bear- ings in general use; the plain, roller and baU bearings.
Bearings are called upon to do two kinds of work; to take a radial load or a tbmst load or a combination of both.
A radial load is load or pressure perpen- dicular to the shaft supporting the load. For instance, the wheel bearings of an automobile, when running on a pyfectly level road are subject to radial loads.
Thmst load is a load or pressure parallel to or in direction of the shaft. When the automobile strikes a curve a thrust load is imposed on the bearings in the wheels — that is, to the side or endwise.
fWe might iUiutrate tb0 relation between thmst Mid ra41u loada In this way: A man could be eoniidered ai being subjected to pure radial load when walking on an absolutely level surface, flg. 8. but when this man walks alons a hillside, with- oai either ascending or descending the hill, as Illustrated in flg. 9, he is subjected to a combina- tion of radial and thrust load ; the thrust load hav- ing a tendency to push him down the hill.
If a atralght roller were called upon to take a thrust load as well as a radial load, it might be compared to the man in flg. 10, he would need a crutch to prevent his toppling over. Therefore a ball thrust bearing (flg. 7) would be necessary at end of the straight roller bearing, per flg. 12.
Plain bearings are usually on the main crank shaft, cam shaft and connecting rods of an engine and take a radial load.
Plain bearings can also be designed to take thrust loads.
BoUer bearings are used in the wheels, rear axle, transmission and other places and when stralghti as per fig. 2, they can only take a radial load. The roller itself runs over an inner race and inside of an outer race, case hardened.
When a roUer is tapered, it runs over a cone type hardened race (fig. 1), and inside of a outer race, arranged as per fig. 11 and pa^e 687. This type of roller bearing will take a radial and a thrust load without the use of a separate thrust bearing.
The groove in the race and roller, fig. 11, take the thrust load as well as the con«t shape of race.
A straight roller bearing, to take a thrust load as well as a radial load, would require a separate thrust bearing, fig. 12 and flg. 9, page 676.
Ball bearings are also used on the wheels, roar axle, transmission and other places.
They are di- vided into three g e n- end classes; cap and cona^ anno- 1 a r and thmst*
The cup and cone bearing is shown in fig. 4, and is used on many cars in the front wheels. This type of bearing is used ex- tensively on bicycles. It is designed for radial loads but is capable of wit&tanding considerable thrust also. It is adjustable.
L^i^i] S^ bearing is a bear- 1^^^^ r^'Ti ^°fi> with an inner and outer race, which is grooved and hardened. They . ^^^^^ are not adjustable.
LJ IV ii Jl Pji "single row" of 9*^ HBHI^aii^^,^ balls, per fig. 8 and 5, or " double row, " &g, 6. The single row takes a radial load. The races of the double row are so shaped, that it will withstand considerable thrust as well as a radial load. It is used where space would not permit the use of a separ- ate radial and thrust bearing.
An example of where a bearing of this txp* it used is shown in flg. 4, page 82. Note the double row bearing is shown on the rear end of the worm taking the thrust (which is eoniideiable). and also takes a radial load.
The ball thmst bearing is shown in flg. 7. This bearing can be used only where the load or stress is strictly a thmst or end to end load.
This type is often used in clutches and it ex- tensively used on the propeller shaft driying the propellers of motor boats.
The two parts the balls touch ara called races. The one or two balls at the lower aide support the entire weight and must be strong enough to hold up without being crushed. In automobiles, the balls are large and run in size up to 1 in. di. hardened and polished.
Sometimes balls wear flat or crack; if so a click will be heard and must be replaced with perfect balls at once.
*See page 681 "adjusting front axl«> t>oarini;8" and page 669. "removing rlhr axle shafts.'* tFrom Automobile Dif^est.
L
CLUTCHES. 37
INSTRUCTION No. 5. *CLUTCHES : Cone, Disk and Plate Clutch. Universal Joints.
Purpose of the Clutch.
The word "dutch" as used in connection with automobiles^ indicates a device attached to cars having change speed gears of the sliding type, which permits the engine to be connected with, or disconnected from, the trans- mission, so that the car may or may not move while the engine is running.
The clutch is connected and dbsconnected from fly wheel of engine by a foot lever.
When disconnected from fljrwheel of engine then there is no connection between the engine and rear axle.
When clutch is connected with fljrwheel of engine then the power of en- gine is connected with rear axle — ^if the gears of transmission are not in "neutral" position.
If gears are in neutral position then the power of engine would end at the end of the secondary shaft of transmission (see page 38).
While other types of transmissions require clutches, they are of special kinds, and will not be referred to in this lesson. (The Ford, for instance, uses a different principle.)
Because a steam engine has behind it the pressure of the boiler, it can be called on to supply much more than its regular horse power for short intervals.
A gasoline engine has no reserve power to call on, and cannot deliver more than a fixed horse power.
When the gasoline engine is required to start the car, it must overcome the inertia of the car. This might be greater than the power of the engine could accomplish, and the engine might be stopped instead of the car being started.
If the clutch made an immediate connection between the engine and the drive, the power of the engine would have to instantly overcome the inertia of the standing car.
The power of the engine coming from the revolving of the fly wheel, and the explosion that might be occurring in one of the cylinders, it would probably be stopped instead of the car being started.
If, however, the clutch is made so that the engine takes hold gradually, the inertia of the car will be overcome, and it will move faster and faster as the clutch permits the engine to apply its power more and more.
This is done by making the clutch in such a way that when it is applied, it dips, instead of instantly making a connection between the engine and the drive.
When the clutch is "let in," it connects the crank shaft of engine through the fly wheel with the transmission through the clutch shaft, and if the gears are in the "neJutral" (gears out of mesh) position, the counter or secondary shaft in the gear case of transmission will revolve without moving the car. See illustration page 50.
Olntches have two chief parts; one part (usually the flywheel, see chart 19, fig. 1), is attaehed to the crank shaft of the engine, the other part (cone or disk or plate) is at- tached to the dutch or main shaft of the transmission (see page 48, fig. 1). (134.)
When the two parts are separated, that is to say ''clutch thrown out" by the clutch pedal, they are independent of each other and the engine can run without moving the car.
*8m Dyka't working model of the clutch and gear box. For repairing clutches, see index. For mako of elnteh oa different ear*, see "Specifications of Leading Oars*' — page 548.
\
C^."--^
.2.rjiz &s ifr
"1 Fig. 1— niustrates • tzw the cone type ' cf clutch is fitted I into tlie fly wheel.
Ill ,: stmt ion showa ?a.z.v in section aa if :::: in half. The : : - :- is perfectly ::rcu!ar, but cone shaped and fitted
^ -^r.h leather which !
' irrir? the inner sur- j fa?e of the fly ! wheel rim when -•lurch is "In," "Which it always is, u::!-?«s thrown
; *;out" by the ' ; olutch foot pedal
. I Note in illustra- I lion position of cone [when clutch ii ! "in" and "out"
* Also note clutch
CE . page 50. ::• threw clutch out. At
I .
.:or ^h.lIt. Noti- tirivo
P -7 ARE POlMTS V.HERE POWER TO REAP AXLE CAM BF C
> povor :- transmuted from engine to clutch, thence to secondarr
■ :•;. • ..••:. >l.aft. drive pear (O), secondary ihaft gear I
.• drive:; ^^mf i - h'..-:iug gears (X) on square shaft (T). '
.:'•■-! i% "out." at which time the elntch '
/. ■ .•■-:; t.':i' drive and drlTen gears are in *'nen- ,
I' ■.' f:-.- ii. end of clutch shaft, as per fig. 3,
,U ;ution: N'"'.'" tl.*- p-wf-r from enji:;'' i:-* trar.smitted to the clutch shaft only V:o\liiti-h \vi.- f. Ill tli' rin: of tKo :"v v;hov\ .'if disk or plate type, then by the
. ., ,., ,.v :!:..!.. I • r.-li-- t»;.t tyj.o -.f rlutch).
!■ .• '\-i>K'\ uiiii ii.irinc, but runs ftee at all times in
' ^ ' 1 i- ...1 .• ;.:i ..{' .'i.^'li I- .••.liiifctril with the clutch shaft so that
• .,1. .iinr! ri.u:-t nl-" tun.. Hut obstTve that the cone slides on the
. , "..', •..;■! v.. :!•:!♦ ;i .Mil h" piKii' 1 out by pedal OP in by the spring. ...I.. . out. i.f ily \\''M"-i power ends at the fly wheeL V iu. I Ml. i)«>\vt»r riids at t!io cud of the secondary or countershaft— if geare
I '
.,iO to VOVt»lVl\
Jl.i \ .I'l- in :iIm-\ . •■.«• m.:i!iii -: .■•!" * ' i.oi!» tmI' ' and scc in figs. 1, 2 and 3 hon
I'l V\r''»"'^''^V''. tlio Puiposo of a Clutch and how the engine can run yet not drive the
,'.!.'. ...t ' ' au.l ' ■ »l'.itrh in.' *
CLUTCHES. 39
When the two parts are connected, that is, when the clutch is 'Met in'' hj re- ieaaing the elnteh pedal, the part on the transmission shaft is forced into a frictional eontaet with the part on the crank shaft or fljwheel by means of a powerful spring and held there. The two parts being thus connected forces the transmission to revolve with the engine and so drive the car, if gears are not in ''neutral" as has been explained.
The part on the crank shaft does not grip the part on the clutch or transmission shaft immediately, unless they are moving at the same speed.
If they are moving at different speeds, which is usually the case, or when the part on the transmission is stationary, the two parts slip. This riipping continues until the two parts revolve at the same speed, when they bind together firmly. When "thrown out" they muBt separate instantly.
A disk or any other type of clutch used with the gear type of transmission is placed in the same relative position; back of fly wheel, between the fly wheel and gear ease. Although the construction may vary, the reader will note that the dutch principle is nee* •osary on all cars.
Clutch pedals — The left foot pedal on all cars of standard design, is the dntdi pedal and on the right the foot brake pedal. See ''operating a car."
Types of Clutches.
There are four types of clutches in general use ; the cone, disk, plate, and fezpanding type.
The disk clutch (formerly called the multiple disk) is a clutch with more than three disks and can be a lubricated disk clutch or dry disk clutch. A {date clutch is one wherein one plate is clamped between two others.
♦The Cone Clutch— see chart 19.
This type of clutch is built into the fly wheel, and the fly wheel forma one of its parts. The rim of the fly wheel is broad, and the inside of the rim is made slightly funnel-shaped, forming the surface against which the other part of the clutch presses (fig. 1, chart 19).
The cone; the other part, called the '^cone," is, as its name indicates cone-shaped, and fits into the funnel formed inside the fly wheel rim. The surface of the cone that bears against the fly wheel is often covered with leather to give good grip (one large manufacturer uses fabric running in oil).
The hub of the cone has a square hole, so that while it may slide on the square part of the clutch shaft which connects to the transmission sleeve (see 134, fig. 1, page 48), still the cone and shaft must revolve together. The forward end of the clutch shaft rests in a bearing formed in the hub of the wheel, so that it is supported, and yet may revolve independently of the fly wheel.
A heavy spring presses the cone against the seat formed in the rkn of the fly wheel.
When the clutch pedal is pressed forward, the cone slides on the shaft away from the fly wheel, and separates from it, the spring being compressed (see fig. 1, page 38).
When the clutch pedal is released, the spring presses the cone against its seat, and if the crank shaft and sleeve are not making the same number of revolutions, the cone will slip. This friction makes the cone act as a brake on the crank shaft, slowing it, and at the- same time the cone and sleeve are speeded up, so that the cone and fly wheel come to the same speed.
dutch Operation — cone type as an example.
Fig. 2, page 38 (also page 50) — note the power from crank shaft of en- gine is transmitted to the clutch through friction connection with fly wheel, thence through gears, thence to drive shaft to bevel gear drive on the rear axle.
If engine is running, clutch could be "in" if gears are in "neutral" (not in mesh). K gears are in mesh with engine running then rear axle would revolve — unless clutch was "out."
*Sm repair nibjeet for adjasting clatches.
tl%« cinMindisK thoa elatch is yery seldom used. As has been previously stated, a succeasfu] ^ m«at be fairly light at the rim. but with the expanding clutch, owing to its method of opera-
^ this it almost impossible.
40
DTKE^ rXSTSCtmON Nl'MBER FIVE.
Cliiteh lAlnicatad Type.
F!^ 2 tk^-wM the paru of the dutch i^p- tsim tmsk otiMr. Th« dhks (A) ar* al- a vtm faa^ oa «Bciiie ■haft. th« tmaJim B. •:« anaehad U the tranwliakwi ahalt. 'At aad aaaU tfaka (B) as
Tte nri Sas^vs have pins czteadittf froai than, th« taia kaT3^ mlcs m that they may be alipped
disks OB their snds fit insido of tho
la* Urso ftaa^. a&d tbe opoaioga in tho
';ir^ i-iks 7«rai; tk« sMds or pint on the satall
laxf* so 7mm toroc^ thea. Thaa the outer cdgea
iisss ecoc in contact with the inner
af :h« larfe diaka.
ttSiAi aa will be seen from
±pzT* 1. «-3:<h is the dntch assembled, the
art ra^sccted only by the friction
t^« IsTfe and amall dislca. when the
rrrizf preasee i^* parts tofother. The entire
z'lizz'z is placed irside a easing, and mna in oil.
W)MBi tka dEieh pedal la priaaad forward,
:^e ei-x:eh is "thrown ont," the oil then
Siswv b«sw««n the disks, and when tho
;I'::ci is "is" and the spring presaaa tho
i:sks :c««tk«r. the oil is sqneesed ool froai
b<7v<c- s^cB. While it is being sqneesed
cc: : *■• ::::fich is slipping, and it be^s to bind
vh*z :b« pressure has sqneesed it out and
;he disk I in eonsequenco feel the eflteei of
:=* fr:^':ior- When the clutch is
one aet of disks may reroiTe isdtpendtfutly of tla oeker. for they are not connected in any way.
Hele-Shav XMsk CbitclL
In the Belfr-Sknw diak ditck (^. 4^ a aimaar prtsciple is adopted. The plates consist of a of alternate bronae and steel disks mzch tkinncr. T hey are eaRVgaiod to incrcaae tho grip. M HA!f tit rVttn s?« rotably ceaBocted by gioofea with the driring member.
P 0 aad %h^ mli^rs^u tMH with, the driven member. Wken the dutch pedal la released.
'- tbe dat<h 9pnx^ pt«efM tkeoe diaka together, and they all rotate aa a aolid
W%mu Ihc d«l<k p*d»^ is ■ - . . ....
separated^
Ike apring preaaaze ia removed and tho
Bef erring to the illussratioa (flg. 4) tho outer ott-ttgkt caae (1). to wkiek tke driving bronae platoa (16) are keyed, is bolted to tke flywked.of the engine. The In- ner eore (1) is keyed directly to the dntch ahafi and to it arc keyed driven sted platoa (IT).
The clutck ia akown spring (4) which actu preaser (8). To facilitate springs (26) are fitted between tho diaka.
engaged aa normally held by tht tea the ring (T) and tke aiidlB| itate quick diaengagement. amaiJ
The ease U oil tight,, provision bdrr of th« oil thr«titfa a plug (6) for the ^'^
AdittttRient^ »f# msde by means cf an sd|iutl^f nxiX {%}, and J c>ieaisit« epinniiitc or dragging is prcveiited by a eeue brake (10).
Fig. 4 — The HeleShaw corrugated disk clutch- lubricated type.
CadUlac— Dry Disk ClutdL
Fig. 6— The drlvliig disks **A'- are covered on both sldoH with a friction material, composed largely of as- beatosi and aro driviMi by six keys in the clutch ring •Ml" whioh is bolted to' tho engine fly wheel *'Q."
TI16 driven disks • * U " are not covered. These disks aro I'lirriiMl on tlio clutch hub **E'* and drive it through ail hi'VM <»n the hub. Tho clutch hub is keyed to the IrKMHiniNHion Bliuft **1'\**
Wlioii tho clutch Is engaged by allowing the clutch ppdiil l»» «*«»nii' towar«i8 you, tho spring ''CV forces all of tho diNliN togt'lhor. Tlio resulting friction between thn iIIhUh "A" and *'M" drives the transmission shaft
' I'"* niiil till' riir. when tho
transmission control lever ! la hi iithiT Ihiin tlio neutral position.
Thorn iiro no adjustments. The clutch pedal should lin iiiljiifil«'i| orraHionnliy to compensate for wear on Ihn riiciii^ of tho clutch disks.
Thn.' In fiiio jioini * ' D * ' on the clutch for lubrication.
Tl.iiin mr 17 .H'i.| plstcii. havinir 9 driven disks and 8 driv- li.i .h.li. Ti.n iMill R|irini; is held under 300 lbs. compression.
Fig. S — Th9 Osdilisc difk rltitcb — Axj type.
////AUT NO. S50 Disk Clutches; lubricated and dry tjrpes.
CLUTCHES. (y^ J
Therefore there are three methods of cutting off the power to rear axle; (1) stopping engine, (2) by throwing **out" clutch, (3) by having gears in "neutral."
The usual method to stop car and engine — is to "throw out" clutch, shift gears to "neutral" and apply foot brake. After car stops tiien turn off ignition switch and stop engine.
Wlien startliig engine the gears are placed in "neutral" position by the hand gear shift lever. (Note fig. 2, chart 19; also page 50. Gears are now in "neutral" position.) Engine can then be started without car moving.
To 'start car after engine is started; throw "out" clutch with foot pedal — shift gears in mesh (usually to lowest gear sot), then gradually let clutch "in."
The term "clntch in" meaus, the clutch is aUowed to press into the fly wheel by tension of spring.
The term "clutch out" means it is held out by foot clutch pedaJ. If car was run- ning and you desired to coast, "throw out" clutch or disengage gears.
Wlien stopping — throw "clutch out" by movement of foot pedal. (Usually left foot pedal.) Apply running brakes (usually right foot pedal.) Shift gears into "neu- tral" and then let "clutch in."
The clutch is used more than any other control on car — therefore study the meaning of "clutch in," "clutch out," "gears in neutral."
When the change speed gear is to be moved to a higher speed after starting or at any time when car is in motion or engine running, the clutch must first be "thrown out," for the gears could not be meshed with the countershaft revolving and the square shaft stationary; "throwing out" the clutch leaves the countershaft free to move as neces- sary to mesh .the gears.
The cons clntch adjustments are simple. Examples are shown in the repair subject. See index. The "grabbing" feature is being done away with by insertion of springs^ usually about 6 inserted aader the leather. Slipping is overcome by clutch springs within the spider. See Buick clutch ad- justment in repair subject.
The Disk Clutch— see chart 20.
The disk clutch (formerly termed multiple disk), consists of a number of disks which are pressed together when the clutch is "in," the friction between them causing one to drive the other. This type of clutch is very compact, and is frequently built inside of a metal housing cast to the engine frame.
To illustrate the principle of the disk clutch, place a silver dollar be- tween two silver half-dollars, and squeeze them together between the thumb and forefinger of one hand. With the other hand, try to revolve the dollar not moving the halves. It requires only a slight squeeze to produce sufficient friction to make it impossible to move the dollar. ^
Multiple disk clutches are of two general types; those {hat operate in an oil bistth and those that run dry ; called lubricated and dry types
The lubricated disk clutch runs in oil; its disks are usually alternate . steel and bronze or all steel disks, and the type that runs dry is usually of steel disks, one set of which is faced with a friction material of woven asbestos fabric.
The lubricated and dry types are described in chart 20.
The Plate Clutch.
The S. A. E. term the disk clutch (formerly called the multiple disk) ; a « clutch with more than three disks. The plate clutch is where one plate is clamped between two others.
The single plate clutch is a popular type of clutch. It is a variation of the disk type, the latter comprising a large number of narrow disks, while the other usually consists of but three broad disks or plates* the ordinary type having two driving plates and one driven plate.
An example of a single plate clutch is described in detail in the following matter. In this type the clutch effect is created by wedging the plate. The type which will now be described is the Borg and Beck make (chart 20 A, and page 43).
42
DYKE'S INSTRUCTION NUMBER FIVB.
1 — Olotch-Oasing — cast with fly wheel. 2 — Oating-Oover — carrying adjustment-ring. 8 — Oover-Slot — for adjustment-bolt. 4 — Adiustment-Bolt — for take-up action. 6 — Adjustment-King — mounts thrust-leTeri. 6 — Thrust- LeTer (bell-crank) — ^mounts roller. 7 — Thrust-Roller — acts against thrust-ring. 8— Thrust-Ring — acts against asbestos ring. 0 — DnTing-Pin — for thrust-ring.
1 0 — Frirtion-Hinji— ssbpntoi.,
1 1— Friction Diflk — drir^n.
12 — Pilot B*llBearmg — fop end of abaft
13 — 01 nt^-h- Shaft — drlTen by di»k.
14— Thnnt-Sprlog — leli mi *' bel i -crank *■ tm
mUflion. 15 — Throw-out Oollai^— on throw-<mt iTe«Y«. 36 — Throw-otit SleeTe^ — eentered on abaft. 17 — TT) rnw-nnt Tf>kf' — runn -mt f^t ;ri j^. 18 — Thrust Bali-Bearing — takes throw><mt pu 19^Brake*PIate — rigid on throw-out yoke. 20— Brake-Oollar— keyed on shaft. 2 1 — Detachable-Oasing — self-contained dutch. 22 — ^Mounting-Flange — bolts against flj whee 23 — Driving-Bolt — for thrust-ring (not ahowi 24 — Shaft. Brake and UniTorsal Oonneetlon (i
shown). 25 — Adjustment-Incline — ^take-up seat for roll 60 — ^Bell-Orank PlTot — mounts thruat-leyer.
Borg ft Beck Single Plate dutch.
Principle: This type of clutch runs dry. The action is best understood when it is ke in mind that among the revolving parts, only the driven group; disk 11, shaft IS and bra collar 20, can stand still when fly wheel is running; and all other parts being ''anchored to fly wheel must always revolve and drive with the latter.
Wlien clutch is "in:" The asbestos friction rings 10, though not positively attached either the driving or the driven parts, will, in practice, "freeze" to the unpolidied fa< of the inner case of fly wheel and thrust ring 8; and thus always run bodily with the : wheel.
When clutch is "out:'* The foot lever is applied which telescopes the coil spring (1 back, by action of the throw out sleeve (16) which causes the roller (7) to withdraw a sui eient distance from faoe of thrust ring (8), to permit the latter, with its companion fr tion ring (10), to "back-away'' bodily, from friction disk (11), thus releasing the disk fr< the friction-grip, anil pcrniitting it and other driven parts to come to a stop, while fly wh< and parts anchored to it revolve.
CHABT NO. aO-A— Principle and Construction of a Modem Single Plate Clutch — dry t3rpe.
Borg and Beck Co., Molino. 111.' -—soo nUo pngos OOS and 842.
8«« index for "Spf.'ifiratior* of Losidinir Cnrs." for cars ii«!injr this clutch.
C!LUTCHES.
43
tAdjusting the Single Plate Dry Clutch— per chart 20-A. Take up action: The roller seat face of the thrust ring (8), is formed on three, equal iaeeeedingy takeup "inclines" (26); the ring being \i inch thicker, at the high end of •aeh ''incline" (25), than at the beginning, or low end. The three thrust-levers (6), are mounted upon, and equally spaced by, the adjustment ring (6); and this ring is ad- justably mounted against the inner face of the cover (2), by means of the adjustment — bolts (4) of which there are two, through slots (3) in the cover.
When the bolts (4), are ''slacked," and shifted in their cover-slots (3), they control and shift with them the ring (5), the latter carrying with it the levers and rollers (6 and 7) — thus shifting all the rollers to new seats against the non-shifting thrust-ring; and, these •eata being further up the ring "inclines" (25), where the inclines are thicker in cross •eetion, the ring is necessarily thrust so much further toward the other friction parts, to eompensate for any friction wear, and to maintain, at all times, a perfect friction grip.
Therefore to adjust dutch, the clutch is held entirely out.
With the clutch thus held "out," it is only necessary to "riaek" the adjustment- bolts (4), tap either of them "clockwise," in the slot (3) on cover, a quarter or half Inch, or any other distance required, thus shifting the ring (5), carrying the levers and rollers to ■ew seats, upon thicker sections of the thrust-ring; and thus compensating for th^ frie- tion-wear which made the adjustment necessary.
If too much oil gets into dutch and causes slipping: In this case it will be necessary to unscrew the bolts (4) about three turns, have some one hold out clutch and let oil drain out. It is also desirable to squirt gasoline into interior of clutch to wash out the oil. If slipping continues the trouble is due to oil working into clutch housing and must be •eparated from main oil supply of oil pan of engine.
Removing clutch: First remove transmission. Mark clutch cover that bolts to flywheel with punch and corresponding mark on flywheel, in order that it is put back in •ame position. Cover plate must not be turned.
Replacing dutch: There are two asbestos fabric rings; one lays against face of fly wheel (10), next, to this comes the driven plate (11), then other friction washer (10). The cast thrust ring (8) comes next, but before installing, make sure the driving pins (9) tre in place in the inside of the fly wheel rim. Drop thrust ring (8) in position so that the three slots fit over pins (9). The adjustment ring (5) with its parts assembled to it ihould now be installed. The adjusting ring (5) fastened to the cover plate by means of two cap screws and cover plate bolts to fly wheel.
Olutch brake is provided which comes into action when the clutch pedal is pushed ill the way down. Purpose is to stop spinning of transmission gears when clutch is dis- engaged. The throw out collar (15) presses against the brake collar (20). The dutch brake is mounted on the transmission shaft and is faced with asbestos fabric.
If worn, trouble will be experienced when shifting gears into first speed when car is •landing. Clutch will appear to drag and will continue to drive transmission gears when folly duengaged, so it will be difficult to mesh gears.
To remedy, remove oil pan, have some one hold out clutch, while throw-out dutch and collar are examined; to see if collar (20) actually touches brake or not. If it does lot, the transmission should be removed and if brake friction facing is in good condition 10 need of installing a new one. See that the throw-out is not coming in contact with brake flange and should be adjusted so that these two points form a contact.
Note — always remember to drive with foot off the dutch pedal. Make sure dutch pedal does not strike or press against toe board. •
♦Unlyersal Joints. A universal Joint is a flexible connection between two
shafts, which permits one to drive the other, although they may not be in line. Refer to figs. 2, 3 and 5 and study the prin- ciple. Universal joints are usually placed forward and rear of the drive shaft (see page 50).
Universal joints are necessary on automobiles with shaft drive, for while one end of the driving shaft is attached to the transmission shaft, which is on the frame^ the other end is connected to the axle, and constantly moving up and down as the wheels follow the roughness of the road.
^^^^ ^ If no universal joints
were used, the shaft would jam in its bearings from the up and down movement of one end of it.
*UBiTerMl Joint! are alio called cardan joints. See pages 680, 681 for construction of ''universal Joints." tSee pages 668 and 842 for other adjustments on Borg and Book clutch. See foot note page 662. why gears of transmission arc snmet mes difficult to shift.
DYKE'S INSTRUCTION NUMBER FIVE.
-A
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Tli« «ticl&* of tliJi unit power
ii « ■ d cjliad«rt ca«t in hloek ; vkWet on tide, poppet tjrp*; d«« t«ehable cylinder beid dee index. ' Vylindpr b • b d, rtpUeint of/*)
Trttimnlitiiloo; lelectiv* %TP9, t •peedB «beiia »iid reTeme. Olntcb; rone t vpe. Gr«af sUn l«Ter; ball fttid locket typ«.
Left, foot datch pedAl Ukd ri^t, foot brkk* p«a«L
Power is trt>iti' milted to rear &z1e from end of trftnsmitiion •baft (npper out).
Fig« 1: A aod«rn unit power plmnt, iLe Dort.
PIQ <t L«aiwlrfl* CJMMrtt. TTi« * M'* T>»> a.r. TM * ii" ryjt* UJ
Tig, 3: Unit power plant wltb valves in the hpud and a detacbable eylioder bead. (The Oakland aU). Tbe bead it d^-iachrd with valvea. TbU di£fera from fif. 1, in that the bead i« dalaclLabl*. bot Ibe ▼aUei are not in the bead in 1kg. 1,
indcr bead.
Tbe Duick 4 cylinder enrinr unit power plant witb ralvef in the bead and deiacb«ble C7I- Note tbe Delro "ainfle nnif elaetrie system ; stMtinc motor, ganerator A04 Ifnltion la
Flf. 4: TUe Locomobile angina and datcb ftra la oa« nniti but the traasadssloa Is onirvrtal Jioiat (T. U. J.) between tbe cinteh and trAnsmistioD — tee alio page 41^9.
ttparata. Kola
CHABT KO. 21-~XrDlt Power Pljmt; engUa, eluteh aad tranamiasion mounted ia one unit Sep^nttfl Power Plant. Engine and dutch form one unit. Tranamisaion separate.
(Cbart 22 on paft 00}.
T]4a Bnirk 4 tylindcr car wai diieontlflned fa 101 T.
^im
46
INSTRUCTION No. 6.
TRANSMISSION: Principle of Operation, Lx)cation, Different Types.
Principle of a Transmission.
When a bicyclist wants to race on a level track, he gears up his wheel with a larger sprocket so that one revolution of the crank takes him farther. Tet if he takes this wheel with this large sprocket on the pedal shaft, out on the road where there are hills, he must get off and walk or exert an extra lot of power. This clearly shows that if a bicyclist wants to speed while on the level and yet take all hills, he must change the drive sprocket.
The same principle applies to the automobile — therefore the automobile is provided with not only two .changes of gears (instead ot sprockets), but it has three and sometimes four changes of gears, which gears are contained in a gear box usually placed back of the clutch. (See page 38).
The principle upon which all change-speed gears work is the fact that when two cog-wheels or spur gears are meshed together the larger wheel turns more slowly than the smaller wheel.
Ab an example, a cog-wheel with 10 cogs, in mesh with a second wheel having 20, would revolve twice as fast as the latter, the explanation being, that when the 10 cogs of the smaller wheel have moved round once they will have engaged with only 10 cogs of the larger wheel, and therefore will have tamed tiie larger wheel through only half a revolution, that is, that it will be necessary for the smaller wheel to revolve twice in order that the larger one may revolve once.
•With this piece of elementary information, we will observe that in the gear-box (see below) there are two shafts — the upper one coming from the engine through the clutch, and the lower one continuing to the back axle.
Each shaft is fitted with three different sized cog-wheels numbered in the illustration 1, 2 and 3; those on the upper shaft are fixed to the shaft itself, but those on the lower shaft are able to slide on a keyway, to right and left along the shaft. The shaft is not round like the upper one, but is iqnaredy so that although the sleeve of cog-wheels can slide backward and forward, they cannot revolve independently of the lower shaft.
In order now to vary the speed of the car, it is only necessary to slide the cog-wheels (gears) along the lower shaft until the correct two gears come into mesh to form the gearing required.
The illustration, for instance, shows intermediate speed gear in mesh, but were we to move the gears to the right so that wheels 1 and 1 come into mesh, we should put the car on its first speed, that is its lowest speed, so that with the engine running normally the car would be moving very slowly, the driving gear being much smaller than the driven gear.
When, however the sleeve is moved to the left so that gears 3 and 3 mesn, the effect is reversed. Now we have the driving gear much larger than that driven, and the result will be that when the engine runs normally the car will be traveling at a very high speed.
*Tbis illustration ii intended to simplify the explcvnation. In actual practice the arrangement is sUfhtlj different (see page 46); the sliding gears are usually above, clutch shaft and transmission shaft are not eontinnoas as shown and drive shaft connects with transmission main shaft instead of foanter shaft.
TRANSMISSION.
c
TrMumiftsioB
Drive 8b«ft
Clutch
MJnWeraal Joint
I. Sliaft drire typ* o' transmission. Trans- mounted on frame directly back of clutch and i tttkT type. This type used to great extent rare cars. TraDsmission of the gear type.
Clutch
Fig. 5. Single chain drlTo type of pUnttirj transmisaloii. The transmission is mounted to the side of the engine. The type of transmission is the planetary type. This system Is now seldom used.
*ran8mission
m
Driving j
Pinion _ ^
Driving Chain ^
Doable chain drlTo typo of transmission, ion is mounted on frame and is connected :ears to a jack shaft. This type used to a tnt on trucks. Transmission of the gear
Fif . 6. Shaft dxlTo typ« of planetary trana Bdnlon aa nsod on the Ford. (See Ford Instruc- tion.)
\m tarm ot rrlotlon Drlv* Trmniaiaalfln^ S
Dvlth gfrm varlabl* trcm tmto^ ^^*-
io tmMlmm, ^ m
The friction disc type of drive of trans- Mi on the Carter Car. It is extensively rcle Cars.
Ff«. 7— The method of placing the gear typo ttaaa- mission on the rear axle. See also page 204.
'^Flg. 8 — Four speed selectlTe typo of transmission for a double chain driven drive car.
The only difference between this type and the ono ia (Chart 23). is that a jackshaft with bevel gears (N), la employed. (See flg. 8 above.)
When there are four changes of speeds, note that thara are three shifting forks (H. J and K). The drive fftar (B) is attached to the sleeve (A), which connects with engine drive shaft through the clutch.
A — Sleeve driven by engine.
B — Gear on sleeve.
0 — Gear on countershaft.
D — Low speed gears.
E — Second speed gears.
V — Third speed gears.
G — Clutch for high speed.
H — Rod and arm for third and high speed.
.7 — Rod and arm for low and second speed.
K — Rod and arm for reverse.
L — Finger in groove.
M — Guide plate for selective lever, also called a
"gate." N — Bevel gears to jack shaft. O — Idler for reverse.
24 — Location of Gear Box (Traiimlssion) Four Speed Selective Type Transmiflsioa.
is oil pape 50). *Sof' patro r.l (footnote) for 4 speed ratio of gearing.
48
DYKE'S INSTRUCTION NUMBER SIX,
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OHABT NO. 23 — Simplified Illustrations Explaining the Principle of Operation and the Ohaagv Qeaxs in a Selective Type of Transmission with Three Speeds Forward and Bereane. Note in modern transmisidoiis the transmission shaft (130) gets horizontally over the eoonti shaft as per page 44. Another change made in some transmissions, is the eUminatioB dogs (189): the gear (128) fits internally into the main drive gear (8G-1). See page SO.
*Al«o called "secondary shaft."
SUDirtO GEARS DIF
48 The Selective Gear Type Transmission.
This type is preferable, due to absence of noise of gears and ease q| operation. The gear change ratio or gear desired, is ** selected" by movement of the gear shift lever and the shift can be made without one gear passing through an- other.
Belatlon of the gears to the clutch is shown in fig. 7y and llg. 2, page 38. Principle of the selective type transmission is shown on pages 48 and 60.
Referring to fig. 7, note power Is transmitted ftom fly wheel to clutch, thence clutch tfhalt to gear O and 8, through sliding ^car for 1st or 2nd speed. For high speed, smaU dog elutches on sliding gear X, on square shaft (T), mesh with dogs on gear O, which makes the drive direct to rear axle, see fig. 3, page 48.
Operation of the Oear Shift Lever. There are two types of gear shift levers; the "gate" principle as per figs. 4 and 2 below, and the "ball and socket" type shown in fig. 1. The latter being used more than any other type.
A itanplified explanation of how the parts operate is shown in fig. 4. If the reader will first refer to page 48 he will understand just how the shift lever operates in relation to the shift bars (146 and 147) and shifting gears (SG-l and SG-2). Further detail will be given below as follows: ^ _
^^ By moving lever (73) in, to the
left, the arm (145) engages with gear shift bar (146). Then by moving it (73) forward or back- wards, the sliding gear (8G-1) is moved to "second" or "high" speed engagement.
Fif. 4: View showing how the gear shift- tag tow and selector connects with the ■Uftinf bars. Lever is now in * 'neutral" position, bat if pushed to the inside it M'ould ikift the inside bars (146)— if pushed to osUide position it would shift the outbide btrs (147).
/
By moving (73) out, to the right, this action causes arm (145) to engage shifting bar (147) which shifts sliding gear (SG-2) forward; forward move- ment of lever (73) throws slid- ing gear (SG-2) in mesh with "reverse" speed gear on counter shaft, while a backward Biorement throws (8G-2) in mesh with '*low" speed gear.
__ _ When lever (73) is erect and in between the two slots as
shown in illustration fig. 4, the slots which (145) work in are in line and all gears are out of mesh, or in "neutral** as it is called. For instance, the gears in fig. 2, page 48 are out of mesh, and slots on shifting bars are in line, therefore gears are in neutraL
Gate type: by studying the il- lustration fig. 2 on page 48 and figs. 4 and 2 on this page, the reader will readily see how the gears are shifted.
The lever (73), the gate or selector (76), and the other parts are numbered and named.
Note this lever moves side- wise as well as forward and back- ward (see figs. 4 and 2).
The ball and socket type of gear shift lever is identically the same principle except the move- ment of lever (73), fig. 1, is in a ball and socket instead of a
gate. Note arm (145) serves the Pig. i. — Ball and Bocket type same purpose as arm (145), fig. 4, of gear shift lever (73) is now above This tvne ia the tvrie "tanding upright in cent»»r of aoove. inis lype is me lype ^j^^ .o^ket and is in "neutral** in general use. position.
tng. 2. — Oafce type of gear shift lever is now in "neu- tral" position (M). The hand or emergency brake lever to the nght is "aet" oatil ready to sUrt car. (1) la **low speed" position; (2), "aecond or intermedi- •U;" (S) U "high" speed; (E) reverse. Movements rsry on different esrs. (See iadez "gesr shifts of Issd- iBff cars.")
*Vots ths movement of gear shift lever in fig. 2. This is the type used on the Overland model 85.
na B0TeB«it of Iffvsr (7S) in fig. 4 vsrlss slightly from movement of lever in fig. 2 this psgs. Wm laffrnrrn If lever (78) in fig. 4. it shifted in to the left and back, we would have 3rd or kigk ipesA; if to tiM Uuft forward. 2nd spaed; if to the right side and backwards. 1st or low speed and if Ui tts tit^t side, fonrsrd, nffscse speed. (Set fig. 4 this page and fig. 2. page 48). TTkls is the standard 8: A. E. three speed gear shift. Illustration is that of the Overland, see SMM 490, 497 snd 858.
DYKE'S INSTRUCTION NUMBER SIX.
OHABT NO. 2S&— Principle and Operation of a Single Plate Olutdi (see page 42), fl^lectiye Tj9 of Trannmlwrion and Method of Driving Bear Axle. A modem Unit Power Ptant Tb clutch may be of any one of three types; cone, disk or plate. The tranemisrioii is a thre speed and reverse type.
(Ohmrt 38 i» on pace 48).
CJEIANQE SPEED GEARS. 61
How the Various Speeds are Obtained By Shifting Gears.
NOTE — The dutch is always engaged or in — unless held out by clutch pedal. Therefore gears must be out of mesh or in neutral before starting engine.
When shifting gears, engine is supposed to be running, therefore always hold clutch out while moving the change or shift.
Never shift from high to low gear, unless ear is slowed down to a very low speed.
Obtaining Various Speeds. Before describing the operation of changing speeds, it is most important to aotiee in chart 22, that the main shaft of the transmission (4) is not square eontinnously right through the gear box. One end (E) works free into end of clutch shaft, so when gears are in ** neutral" or not in mesh, there is no con- nection between clutch and transmission. A study of fig. 3, chart 23, will assist the reader in understanding this. Also note remarks under ''clutch shaft'' in chart 22.
''Neutral;" by observing the position of gears, it will be noticed that none of the gears are in mesh except the main clutch drive gear (9) (called clutch gear), connected with the clutch shaft and the gear (SS) on the countershaft. If we then follow the dotted lines and arrows it will be noticed that the coun- tershaft (22) and gears (23, 21, 20) thereon are free to revolve.
Low or 1st speed: the gear shift lever (1) is brought to the center, and then drawn side wise until the lower end of lever engages with shift bar which oprates (6). This gear (5) is then moved into mesh with gear (21). The power then is from gear (9) to (SS), thence (21) to gear (5), thence square shaft to propeller or drive shaft.
Intermediate or 2nd speed — is obtained by returning the gear shifting lever to "neutral" (straight up and down, position illustration shows lever now) ; then putting end of shift lever (1) in shift bar which connects with (7). Push lever forward, this will slide gear (8) into mesh with gear (23). Note dotted lines then for the transmission of power.
High or 3rd speed — also called "direct" drive: Pull lever (1) straight back. This will shift sliding gear (8) over gear (9).
The drive is then direct through gear (9) and gear (8), through square shaft to rear axle. The action causes gear (9) to partially mesh inside of gear (8), as gear (8) is fitted wiht internal teeth. The former method was by means of "dogs" (139), fig. 2, chart 23.
The engagement of these two gears cause the top transmission or square shaft to be engaged direct with the clutch shaft and continuous right through to rear axle.
During the time that the direct drive is on, it will be noticed that the countershaft or secondary shaft (22) although doing no work, is still running. In a few instances, makers have arranged that this should be thrown out of action as soon as direct drive is on, but owing to the diflficulty in connecting it up again when the second speed is wanted, it is now generally allowed to remain in mesh.
♦Reverse: When the "reverse speed" is required the gear shift lever IS brought to "neutral," then pushed forward to mesh gears (5 and 20). There are now five gears in operation instead of only four, as for first and second speeds, and the result is that the square shaft (4) turns backwards.
*T1m rcrerie pinion it set lower down in the transmission case and slightly nnder the counter- «Uft hMiire It in not possible to s^e it. Charging gears, see v&iscs 486, 488.
Th« Xiocomobll* and Pierce Arrow use a four sneed transmlBsion. The direct or hi;;h gear drive ii OB the fourth speed. On the model 22 and 22A Winton the direct drive was on the third speed and the fourth speed was geared slightly higher than direct drive — see page 583
62
DYKE'S INSTRUCTION NUMBER SEVEN,
0if7JU<£flfP£
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p/srOA/jRUNK TYPE
kOMlTHNCCASTMl/ T^WrrLB. 'CO^A/£Cr/NC
mo
'CAA4S
C/fAA/H ViAFT
Fig. 1— The Oasoline Engine; an internal combustion type
P/5rcA/'
£00
Tf^^armB
=3^=^
r^Am ^^SjOoit-£/f T^^AMAt^
SfO^S QF PISTON
mo
SHAFT
CA!S^UNK^
OmNEif
FijBLSi/FF4.Y
Fig. 2--Steam Engine; an external combustion type.
MOTOR.
5/fAFr
freAff Atj^B.
Fig. 3— The Electric Motor and its source of electric supply; the storage battery.
OHABT NO. 25 — ^The Three Motive Powers; Gasoline Engine, Steam Engine, Electric Motor.
Note — An eccentric (E) on a tteam enirine is for the same purpose as a cam on a gaaoline engine: i. e. to open the valve. Although, the word "explosion" is used, under fig. 1, the correct term U com- bustion"— see seventh paragraph, page 58.
ST^ACe
j^SArrEFY I
THE GASOLINE ENGINE. 63
INSTRUCTION No. 7.
*THE GASOLINE ENGINE: General Explanation, Cycle Prin- ciple Explained. Construction of the Gasoline Engine. Assembling a Four Cylinder Engine. Speed Control of Engine.
General Explanation. There are three motive powers for automobiles. (1) the gasoline engine, also called an **intemal combustion type of engine in which the fuel combusts inside of the engine, between cylinder head and piston or the combustion chamber. This type of engine could use either gasoline, kerosene or alcohol, but in this treatise we will deal with gasoline as a fuel. (2) the steam engine is an external combustion type. The combustion taking place under the boiler, separate from the engine. (3) the electric motor (shown in chart 25), derives its power from an electric storage battery.
Gasoline engines: We will deal with the gasoline engine type of auto- mobile. The gasoline engine furnishes the motive power to drive the automo> bile.
Engines for small cars are sometimes made with but one, or perhaps two cylinders (now obsolete). A few motor cars formerly had engines of three cylinders. The majority have four, six and eight. BHve-cylinder engines hardly exist. Seven-cylinder engines exist in a special form for flying ma- chine, as the Gnome revolving cylinder type. The ttwelve-cylinder engine is also coming into prominence ; motor boats indulge in engines with as many as 12 to 24 cylinders. But whether the engine has 1 or 24 cylinders, the ex- planation of how it works or the principle, always remains the same.
All gasoline engines work on practically the same principle. It must be a four cycle or a two cycle type (four cycle is dealt with in this instruction). The valve arrangement may be different, but we describe the various types of valves further on in this instruction. The ignition may be diflPerent, but we cover all forms of ignition. We mention this so that when you see an engine with a diflferent ignition or a different valve arrangement, remember the prin- ciple is just the same on all engines (except the two cycle type, which have no valves. The principle of combustion and ignition is similar, however).
Gasoline engines belong to the class known as internal combustion type of engine. This name is used to distinguish them from steam engines, which are of the external combustion class, for the heat that a steam engine turns into power is produced outside the engine, under a boiler.
In a gasoline engine, the combustion, or in other words, the burning of the fuel, takes place inside of the cylinder of the engine, the fuel being gasoline.
When a mixture of gasoline vapor and air ir set on fire, it bums with great rapidity and produces intense heat, which expands and develops the pressure against the head of the piston, which operates the crankshaft of the engine. This combustion is so rapid that it is usually spoken of as an ex- plosion; and that word is often used, although the word combustion is more correct.
*For enirine repairs and adjuttments, see subject of repairing. **The gasoline engine is also called a "hydrocarbon*' type of engine.
tThe "tweWe" cylinder engine was formerly referred to as the type used on motor boats, where th^ twelve cylinders were in line. The "twin six" is referred to as the type used on automobiles, with cylinders placed •'V** type. However, both terms are used. "Twelve or eight cylinders *V* type " would be the proper term.
mot*— Th« word motor ii often nsed to deiicnate tlie engine, but if one wishes to be technical and correct it should always be referred to as engine. The word "motor," however (owing to the popu- lar practice), is used in many instances in the book.
00£a
The Four Cycle Gasoline Engine *nd Its Parts
Wbeo Jo doubt as to the oajxie» of any t>Arts of the eogine refer to this chart
The type of Tslvet (hoth intake snd eshanst) oo this engine are called ^'mechanically operated valves,'*
The type of cylinder 19 the ^*T*Head type/* iviih the exhaust valves oo one side and the intake valves on the opposite.
tOBAftT NO. 2&^A Four Cycle Gasoline Engine Showing a Sectional View T hend type cylinder, valves are of the poppet type and are rnef'hanically operated- Wrth the T-head type of cylinder the int^ake valves are placed on one side and the exhaust valves on the other side^therefore two cam shafts and two cam gears are required. 'Sea index for Two Cycle Eofistt.
le
3
TUE GASOLINE ENGINE. 66
The difference is that an explosion is instantaneous, while the combus- tion of gasoline vapor and air, although very rapid, is not instantaneous. The eombustion takes place within the cylinder of the engine.
One end of the cylinder is dosed, and the other is open, the closed end being called the cylinder head. Within the cylinder is a piflton, sliding back and forth.
The space between the piston and the cylinder head is called the combus- tion chunber.
The back-and-forth motion of the piston in the cylinder is called recipro- cating motion. In order that it may turn the wheels, this reciprocating mo- tion must be changed to the motion of a wheel revolving on its axle, which is called rotary motion. The reciprocating motion of the piston is changed to the rotary motion of the wheels by means of a crank shaft.
The piston is connected to the crank shaft by a connecting rod, so that it moves in and out as the crank shaft revolves. One complete turn of the erank shaft, by which the piston is moved from one end of the cylinder to the other, and back again, is called a revolution. One-half of a revolution of the crank shaft moves the piston from one end of the cylinder to the other, and this is called a stroke.
It jamat be remembered that there are two strokes of the piston to every rtvolntion of the crank shaft; one down-stroke and one up-stroke.
A steam engine is called double-acting, because the pressure of the steam •eta on both sides of the piston.
A gasoline engine is called single acting, because the pressure acts on only one side of the piston ; on the top or side nearest to the cylinder head.
The combustion that causes the pressure that operates the engine, takes place between the cylinder head and the piston, in the combustion chamber. nie combustion should be timed to occur so that the greatest pressure is ex- erted when the piston is nearest the cylinder head. The pressure causes the piston to slide the length of the cylinder, from the head toward the open end.
In a steam engine, the pressure of the steam forces the piston to slide lint one way and then the other.
In a gasoline automobile engine the pressure from the combustion acts on only one side of the piston, forcing it to slide only one way. After being forced downward, the piston must be brought upward again, and this is done by a heavy *fly wheel attached to the crank shaft. With the downward mo- tion of the piston, the fly wheel starts revolving. When once started, the fly wheel continues to revolve until friction or some other resistance stops it, but before this can happen the pressure is again exerted, keeping it going.
tThe fly wheel being attached to the crank shaft, they revolve together, and because the piston is connected to the crank shaft by the connecting rod it moves with them. The piston moved downward by the pressure, starts the crank shaft and fly wheel, and then the fly wheel in continuing to revolve moves the crank shaft and piston.
Because a gasoline engine does not operate with continuous pressure, during its action the piston first moves the crank shaft and fly wheel, and then the fly wheel and crank shaft move the piston.
Before there can be a combustion of mixture in the cylinder, the mixture must be drawn into the cylinder, through the inlet valve.
When in the cylinder, the mixture must be prepared, so that it ignites, bums and expands with the greatest possible rapidity and heat.
•Largwr Hj whMls «r« used on single cylinder engines than on mnltlple cylinder engines, becaase there are not as many firing impulses to two revolutions of crankshaft on a single cylinder engine.
tThe fly wheel is nsually fitted securely to tapered end of crankshaft and flange, per (92) page 62. It mast Ve secnre. else a knock would occur, per page 638.
DYKE'S INSTRUCTION NUMBER SEVEN,
[ CHART NO. 27— Dlfl6r«nt Tiews o! th9 Outsido o! a Four Cyliodor Gasoline Engine with ^^m_ cylinders oast In pairs. Valves are mechanically operated. Exhaust valves on oae
^B side and the intake valves on the other side. Ignition by magneto. Water clc
^^ dilation by pump.
r KOTE— 'Tlim 'i'" h<>ad lypc of vng^ine could be roastnucted with tho inlet tnd ej^hauxt reverted if necetMry. I Por iattfttico, ialet could be oa the rifbt vido of engine ftnd exbsutl on ih« left tide, at thown In chart 9A. |
I iChMH No, 28 on page 60).
THE GASOLINE ENGINE. 67
After the mixture has been burned, the useless gases must be removed, or exhausted from the cylinder, to make rooin for a fresh charge of the mixture.
These successive events must occur in their proper order, for if any one of them fails, or it is not performed properly, the following event cannot occur, and the engine will stop running. *These events are (»lled a cycle.
The Four Cycle Principle.
There are two distinct cycle principles; generally spoken of as ''four stroke cycle" and **two stroke cycle" principles. The two cycle engine is generally a small marine type of engine and will be dealt with under marine engine instruction.
The four cycle engine is the type used for automobile work, therefore we will deal with this type throughout the automobile instruction.
The cycle is thus composed of: 1st, the drawing into the cylinder of the mixture; 2d, the compressictn of the mixture; 3d, the burning or ignition of the mixture and the forcing downward of the piston by the pressure pro- duced by the burning of the mixture ; 4th, the removal of the burned and use- less gases left after the combustion.
The cycle is performed during two revolutions of the crank shaft, or, what is the same thing, four strokes of the piston.
The first event occurs while the piston makes a downward stroke, during which the cylinder is sucked full of the mixture, just as a similar stroke of a pump or S3rringe sucks in a liquid: this is called the inlet stroke or suctien stroke.
The next stroke of the piston is an upward stroke, during which the mixture sucked into the cylinder is prepared by being compressed, and at the end or top of this stroke it is set on fire, or ignited : this is called the compres- iloii stroke.
When the compressed gas is ignited the pressure from the combustion forces the piston to make a downward stroke; this is called the power stroke.
The next upward movement of the piston pushes the burned and useless gases out of the cylinder : this is called the exhaust stroke.
In principle the gasoline engine is like a gun. In a gun the shot is fired by exploding powder behind it — ^in a gasoline engine we explode gasoline be- hind the piston in exactly the same way.
There are some differences, of course When the charge goes out of the gnn, that is the end of it. But in a gasoline engine, after the explosion drives tiie piston before it, in order to get any work out of the machine, this piston must come back and a new charge must be exploded behind it. The burnt gases and heat must be disposed of and all of these things must be done over and over again very quickly at exactly the right time.
Valves are arranged to open and close at the proper time to admit fresh gas and to let out the burned gas, and the positions of the piston, valves and earns for each function are shown on chart 29. Note the direction in which the cams are turned by the cam gears.
Explanation of The Four Strokes.
Fig. 1: In the first diagram, chart 29, the piston is at the beginning of the down stroke on suction, and the arrows show the direction in which it is moving.
Fig. 2: In the second diagram, the piston has completed its suction stroke and is now starting up on its compression stroke.
*The word Oycle really refers to the complete operation of the four itrokeB of piston to complete the cycle CTolntion. Therefore to distinguish the engine with four movements of piston, from the engine with two movements of pistons to complete the cycle evolution, we will call them: "four cycle" and ''two cycle" types of engines.
DYKE'S INSTRUCTION NUMBER SEVEN.
VALV£ OPEN
EXHAUST
Hift.tTCAM6£Af?i
^HAfrC£AfiTO/^iiS y± REVOlOftort CAM^ iSrffKH ANQ CAM TUf^N^ V^ R£VOLUTfO/V.
£X^ CAM SHAf £r. CAM
rCftANK S/tAi PRIV^ 6SAA '/a. Size Of CAM 6£A/r.
FIG VSUCTfON STROH£Dom FIG Z.POW£R STf^OAE oow
FI6.5.
POSITION
OF
CAMS.
iNLir
CLOSEO
MXHAUSl VALVe
tNUT VALVi LfFTiR.^ tNLET CAM §iAfl^
inlbt cam,
tNierCAtiS^MfTX
FIG.2 COMPRESSION STROHeofi FIG 4. EXHAUST STROAE u
Fig. 1. Snctlon stroke; note charge of gas being taken into cylinder from carburetor by the suction of piston through the open inlet valve. Note inlet valve opened by inlet cam. Note direc- tion of travel of cam, also note this stroke is also called * 'admission" or * 'inlet" stroke. Fig. 2. OomprMsion stroke; note both valves are closed because nose of cam is not raising either of the valves. Note travel of cam.
Fig. S. Power stroke; note the spark is now occur- ring, therefore the compressed gas is combusting. (Bee page 61, note in actual practice, spark occurs before combustion takes place.) Both valves are closed. This stroke is also called "explosion" or "working" stroke.
Fig. 4. Exhaust stroke; note the exhaust valve cam is now raising the exhaust valve. The burnt gas is being forced out the exhaust pipe through muffler. This stroke is also called "scavening" stroke.
When piston reaches top of ezh&nit itroke the ;
ton will have completed the four strokes, or two eri
revolutions, and cam shaft one revohitioii.
The next stroke is the suction stroke again. Tli
four strokes are repeated over and over again aa 1
as engine runs.
The above explanation of the foor atrokes la «splAl
with a "T" head type of engine, supposed to be
in half and standing in front of engine.
The "L" head uses but one cam shaft, there is
one inlet and one exhaust cam for each cylinder. J
the same as a "T" or "round" head cylinder or
type of four cycle engine. The principle ia identiei
the same.
Fig. 6, iUnstrates the morement of tiM earn; note
cam moves 90 degrees or one-fonrth rerrdhition, e
time the crank moves 180 degrees or one-half t\
lution.
OHABT NO. 21)— The Four Cycle or Four Stroke Principle Explained, ejele" engines. (Chart No. 28 on page 60. Ohart 80 on page 70).
See index for
THE GASOLINE ENGINE. 69
Fig. 3: The piston has now completed its compression stroke and the compressed gas is being ignited by the spark at spark plug gap. This Ignitioii of the gas causes the combustion to take place and piston travels down with foroe, the amount of force being governed by the amount of com- pressed gas which was admitted to cylinder by throttle of carburetor. This down stroke is called the power stroke.
Fig. 4: The piston has now completed it^s power stroke and is coming up on exhaust stroke, pushing burned and useless gas out exhaust valve.
Note the inlet valve is raised to admit the suction of gas (Sg. 1) and •xhanst valve is raised to permit the burned gas to be discharged. During the other two strokes (compression and power strokes), the valves are elosed.
fThe reason for first cranking an engine to start it is due to the fact that a charge of gas must first be drawn into cylinder by the suction stroke, then eompressed. After the gas is ignited, then the force of the power stroke, win give more turn to the fiy wheel which carries the piston through the other three strokes until power stroke is reached again. (See page 116.)
Therefore, during three strokes (suction, compression and exhaust), the engine is not developing power. There being only one power stroke out of the four.
In starting the engine with the starting crank, the spark lever (chart 88) must be retarded so that combustion occurs when the piston has begiln to move downward on the power stroke, otherwise it will fire before piston reaches the top and run backwards for half a revolution termed '' kicking or baek firing.''
Additional Explanations of the Four Strokes.
As explained four evnents, called the cycle, occur in the cylinder of a gasoline en- ciae during every two revolutions of the crank, or, what is the same thing, during every four itrokes.
The strokes of the piston during the events of the cycle (as stated previously), are
^ the:
-"Inlet" or suction" or "admission" or "inspiration" stroke, fig. 1, chart 19. 9d— "Compression" stroke, fig. 2. 8d — "Power" or "firing" or "working" or "axploflion" stroke, fig. 3. 4th— -"Exhaust" or "scavenge" stroke, fig. 4. These wiU be dateribed in their proper order.
^floctton stroke; the inlet stroke is a downward stroke of the piston, sucks in the aildoaive mixture. Note fig. 1, chart 29.
The speed of the engine is governed by the amount of gas drawn into cylinder lirongh the throttle valve of carburetor (page 66). If high speed is desired, it is ■•eeasary that all of the mixture possible may be sucked in, for it is clear that if the ^Under is only partly filled not as much power wiU be developed as would result from a fun charge. There must be no obstruction in the inlet pipe to prevent the mixture from entering the cylinder easily, and the inlet valve must open wide enough to admit tha fun charge. (Bee chart 28, 33 and 106.)
Afl the inlet valve is mechanically operated, the cam must be adjusted (by having the lalat cam gear properly meshed with the crank shaft gear) so that it will open the valve promptly as soon as the sucking action of the piston commences, which it is just beginning to do in fig. 1, chart 29. Note the cam is just starting to raise the inlet valve.
If all the openings into the cylinder, as the exhaust valve, the spark plug, piston rings, relief eock, etc. — are not tight, air or gas will be sucked into the cylinder through them at the same time that the charge enters through the inlet valve, and this would destroy the proportions of the mixture.
If the inlet valve does not open soon enougli, the piston will have made part of its stroke before the charge begins to enter; if it opens too soon, part of the burned gases from the previous power stroke will be pushed into the carburetor.
*8«e Djke's worklaf model No. 1. of the "T" head type of gasoline engine, and the four cylinder > Bod^ for the "L" head type of engine.
tne piston of A tteam engine roovea at toon as steam is admitted to the cylinder— beeanae ...Jtaro «ziata in boUor — therefore it is self-starting. There is no pressure in a gasoline engine on- m H la nuiniaf — therefore it is not self-starting. The crank shaft must be turned by hand or an dortriea! or mtehanical device.
eo
DYKE'S INSTRUCTION NUMBER SEVEN.
^ Sparle Plus virs
Fig. 1. In t]il8 view we are looking it the end of the engine. Imagine end cylinder cat in half.
The object Is to llliutrate how the gasoline from the tank flows to the carburetor and fllU the float chamber until the float needle cuts off the flow. The gas, mixed with air, is then drawn i&to the eylinder by the suction of the piston on the suction stroke. Dnring this suction stroke tho inteke ▼aWe must be opened by cam (nose shaped affair at bottom of valve lifter) to permit gas to enter cyllndtr.
After the cylinder Is filled with gas, which is the purpose of the suction stroke, the intake and ax- baust valves are closed and the piston on its np stroke (compression stroke) compresses the g»t. At the highest point of compression the gas is ignited by the spark at the point of the spark plug aad the piston is forced down with considerable force; this is called the explosion stroke. As the piatoa travels up again the burnt gas is expelled through the exhaust valve which should open at this tfaBa^ and permit the burnt gas to pass out through the exhaust pipe and mnfFIer, this fourth and last stroks to complete the operation, is called the exhaust stroka.
Tka spark oeenrs aft spaxk plug whan piston is almbst aft tha top of coaproa- slon stroko. (8ee Pig. 3. Ohart 29).
This spark fs cansod to ooenr by a coil and battery be- i n g eonaeeted to- gether at the rlfflit time by a "timer or commntator" bon- Uct.
The tlBMr arm is roTQlvod by tko euu ahaft to which it is attached. Thereforv It revolvea onee and makea one contact during two revolu- tions of crank shaft, if a single cylinder engine. If a four cylinder, there would be four contact aag- ments for arm to touch during one revolution.
If a magneto ia used for igniton, as in Pig. 1. then the magneto is run from cam shaft and con- tact is made by an ' 'interrupter* ' arm at the right time. See Chart 83.
CHABT NO. 28— Elementary Principle of Carburetion and Ignition; explaining how the gas is sucked into Cylinder by down motion of Piston and how the Spark is made to oecnr at the correct time.
(Chart 29 on page 6>3 )
THE GASOLINE ENGINE. 61
«
If it closes too soon, the cylinder will not get a full charge; if it closes too late, part of the mixture will be pushed out of the cylinder on the compression stroke.
fComiiression stroke. The next stroke up of the piston is the compression ftioke. Am the piston travels up, the mixture cannot escape, therefore it is compressed nntil it oeeupies only the space between the inside head of cylinder and head of piston.
Power or explosion stroke^ at this instant the spark should occur, which ignites the compressed gas causing the piston to be forced down with considerable force. This force or pressure is governed by the amount of gas and compression space in top of cylinder when piston is at its extreme up position.
Too poor or too rich mixture will not bum as rapidly as a proper mixture, and must therefore be ignited sooner.
In getting the proper time for the ignition of the mixture, it must be remembered that it is necessary for the spark to occur at such a time that all of the mixture is to be burned just as the piston is at the top of its stroke — ^when the gas is compressed to the highest point.
The contact on timer or commutator, or the magneto contract breaker in the igni- tion circuit, is so arranged (see chart 33), that it may be moved, in order that the spark may occur in the cylinder at the instant desired by the driver; that is, the spark ean be made to occur early or late by movement of the hand spark lever. AdYtiUBing the spark is to move the timer or contact breaker, so that the spark will ignite the mixture (early) before the piston reaches its upmost point in the cylinder. Betaidlng the spark is to move the timer so that the spark occurs later in the stroke, in some as the piston reaches its upmost position, or even a trifle after.
If tlie spariE is advanced too much, all of the mixture will have been burned be- fore the piston reaches its upmost point, so that it will be necessary for the fly wheel to force the piston upward against the pressure until it gets to its upmost point. This strains the engine, and causes a sound that is called an ignition knock; a hard, metaUie sound that may be prevented by retarding the spark.
It is seen from the foregoing that the qieed of the engine may be also oontroUtd (in addition to the gas throttle lever; see chart 33) by adyanclng or retarding tbe ipKkf the speed of the car changing accordingly.
Brhanst stroke: during the exhaust stroke, the cylinder is cleared of the burned and useless gases that are left from the power stroke.
Toward the end of the power stroke, there is still pressure in the cylinder, and whfm, the exhaust valve is opened this pressure will cause the gases to begin to eseape.
As the exhaust stroke is an upward stroke of the piston, the piston will push out tkrongh the exhaust valve all .of the burned gases that do not eseape by their own
Baek pressure, caused by the muffler or obstructions in the exhaust pipe, will prsTont the burned gases from escaping as freely as they otherwise would, and idl may not be pushed out by the time that the exhaust valve closes.
If all the burned gases are not pushed out of the cylinder, it will prevent a fuU ehmrgo of fresh gas from being drawn in, which will cause a weak mixture and a weak eonlosion.
no ezhanst valve closes as the piston reaches its upmost point, or a little after it, the inlet valve opening as it closes.
The exhaust valve and its seat are exposed to the full heat and flame of the burning mixture, and are more liable to warp or pit than the inlet valve.
It must be watched, and if there does not seem to be perfect compression when the engine is cranked the probability is that it needs grinding to seat it properly.
A proper mixture will be entirely burned before the exhaust valve opens. An Improper mixture that burns slowly, may still be burning when the exhaust vidve open% and will heat the exhaust pipe and muffler so that the pipe may become red hot. Such a mixture wastes fuel, and may result in a fire. It may be corrected by making a eorreet adjustment of the carburetor and spark, which will be explained later on.
fHoi* on word "compression** — the word "{'ompression" as used by motorists in such terms ss "SoeA oomprossioB" or "wtak compression" refers rather to the compressibility of the engine than to the aaonnt of pressare actoaUy obtained in the cylinder, which, of course, varies very mneh with tho smonnt of icas admitted to the cylinder durinfr the suction stroke and also to condition of tho piston rings and other parts which miirht leak and cause the pressure to decrease.
62
DYKE'S INSTRUCTION NUMBER SEVEN.
A — Upper balf of crank case (42), (turned upside down) showing the main bearings (95). Note lower half of one of the main bearings at top of illustration.
-Upper half of the crank case (turned upside down) showing the crank shaft (92) in place in the main bearings.
0 — Upper half of the crRnk case (turned upside down) showing the connecting rods (93) fitted to the crank shaft (92).
D — Upper half of the crank case (turned upside down) showing cam shafts (104) and cams (105). Continued on page 64.
Key to Engine Parts.
Crank Case —
Upper half (upside down) 42
Crank case — lower half 90
Crank ahaft (4 cylinder) 92
Ply wheel ^ 44
Starting crank 48
Main bearings 96
Connecting Bods 93
Crank pin bearing 94
Wrist pin 96
Piston 97
Piston rings 98
Piston pin 96
Cam Shafts 104
Cams (nose shape, which raiae the
Talres) 105
Valve plunger guide 106
Oears —
Drive gear on crank shaft 109
Cam shaft gear 110-111
Magneto gear M
Pump gear 118
Cylinders —
Cast in pairs — ' 'T* ' head 89
Inlet \aive caps 40
Exhaust valve caps 41
Pet or relief cocks 116
.Outlet water connects with radiator. . .116 Studs for cylinders 117
Pump — (Water circulating) 49
Intake water connection 118
Vatres — (Mechanically operated) —
Intake gas valves 119
Exhaust valves 120
Valve springs 121
Manifold- Inlet gas pipe (supports carburtlor
and passage of gas to cylindera) ... 45 Exhaust pipe (passes to mufner and through muffler the burnt gas is dia- charged) 47
Ignition —
Magneto, supplies eleetrio current for
igniting the gas — ^run by gear 58
Magneto distributor 122
Contact breaker on magneto 228
Spark plugs 56
OHABT NO. 81 — Explaining how a Four Cycle, Four Cylinder Oasoline Engine is Constmctad. If the reader will start with illustration (A) and study each carefully he will note different parts are added until the engine is completed.
VOTE: — The S. A. E. now designate the lower part of crank case as the "oil pan^' when containing no bearinga. If it contains bearings, it is termed lower crank case. S. A. £. further designate crank cases of the **^it jhq^e" and the "barrel type." — In the barrel type the crank shaft is removed from one end of erank ease. The bearing caps being removed through hand hole plates. Type shown here and most used, ia the "split type*' with the bearings completely in the upper half as at (A). (Chart 80. see page 70.) -
THE GASOLINE ENGINE. • 88
Types of Engines.
Ab previously mentioned there are several types of engines, all of which work on the four cycle principle. In order that the reader may more clearly understand we will give an outline illustration of some of the different types of engines in general use, see pages 70 and 71.
The type of engine used more than any other type for automobile work, is the four and six, the eight and twelve V cylinder type of engines are also popular. We will confine our attention, however, principally to the four.
Building a Four Cylinder Engine — showing the construction, step by step.
Before the reader can thoroughly grasp the meaning and purpose ef the parts, we will build up a four cylinder T-head type of engine as shown in eharts 31 and 32. We shall then describe what each part is for, and the vari- ous constructions o£ the different parts by different manufacturers.
Khnuik caie: by referring to tg. A, we have an aluminum crank case, upper half part, wUeh we lay on the floor, upside down, so that we can see the bearings (§5).
Tlie beartngB are made in two halves. The bearings are usuaUj made of bronze or white metal and are termed ''bushings" instead of bearings when removable or renew- aUa. The bushings are fitted into bearing caps.
(thin paper or metal strips) are placed between the two halves of the bearing ■0 that when wear occurs a ''shim" can be taken out and the lost motion taken up. Bee index.
Tbe erank diaft (92, fig. B), wiU now be fitted in jthe bearings. The bolts are tightened so that there is no lost motion.
oannectlng rods (93, fig. C), will now be fitted to the crank shaft. The lower half of the large end of the connecting rod, caUed the connecting rod cap, is removed, ■0 that it ean be fitted to the crank shaft. It is then tightened carefuUy, and shims in- nrted so that it works free on the crank shaft, but good and tight, so that thtere wiU be no lost motion. If there was lost motion a knock or pound, which would cause wear, would be the result.
Tlie cam shaft (104, fig. D), with the four cams (105, nose shaped) are now atted to its bearings. In this engine there are two cam shafts; one with four cams for raiMng the four inlet valves, and the other one, with its four cams (105) to raise the four exhaust valves.
The nose of the cams are so placed that they are divided equi-distance apart so that n^en they revolve they will raise the valves, by pushing them up with their nose, at a eertain given time. The timing gears which operate the cam shafts, wiU be explained further on.
The crank case, is now turned right side up, after having fitted the lower half of the erank ease (90) (oil pan). This lower half holds the oil, which the crank shaft splashes in (lubrication systems explained farther on).
The piston or wrist pin (96, tg, £), in small end of connecting rod, is shown in the next iUustration. This holds the piston to the end of the connecting rod (details of eaeh part wiU be explained further on).
After the fonr pistons are fitted to the connecting rods, the cylinders (89, fig. F), are fitted down over the pistons, being careful not to break the piston rings (98, fig. B). (Treated under repair section.)
The cylinden* (39, fig. F) are bolted to the crank case by nuts fastening to studs (117, fig. E).
The valve lifter guides (106, ^g, F) are fitted in holes in each side of the erank ease that thdy wiU come in line with the exhaust valves on one side of the cylinders, and the inlet valves on the other side.
*TMlinleallT th« term "crsnk case lower half" should be **oil pan" and as the term "enuik mam lewer kalf'* it used only when it contains the bearings, whereas in this and most enfinee the taw«r half is merely an oil pan.
64
DYKE'S INSTRUCTION NUMBER SEVEN.
E — Upper and lower half of crank ca^e with Iow«r li»lf of cr&nk cam (90) bolted to upper half (42), The uppL*r ball of crank cjisd it now turned right iide up. The pistons (97) and piston pin or writt pins <90> are showa — alio the studs (117), to hold cylinders in pises.
X* — Tbs eylindsrs (39. cast in pairt^ — ^..-pt* head typo) are now holtDd tn crank e*se. The TSlve plimgor guides (106) are also fltted. The erankib&ft drlTS sw (100) Is fitted to erankfihaft (92). The two camshsft gears (110) are next applied to the cnmshaft (104).
O — This view shows the Intsks vslres (119> in oylinders, intake pips (45) with eu- bttrstor. fltted to eylinders, also ma^sCo (SB), mounted and geared to one of ths cam e^ftri.
-Showb eiJbaust vslTSS (12O4 opposite side of engine)
- •liar * —
with exhaust pipe (47 )» t^llef cocks (41) circulating pump (49). The flywliest (44) la also moiiDteJ on end of crankihaft,
^CEBAET KO. 82— Oonstruction of a Pour Cyclo» rour Cylinder Gasoline Bngtno, Continued. Oar-
ibnTetor, ignition and water circulnting tiyst^m added.
THE GASOLINE ENGINE. 65
Valve lifters are now fitted through these valve lifter guides (see shart 26), wUeh raise the valves through the action of the cams.
gear for drlvliig tbe timing gears, called tlie crank diaft timing gear (l^l), is keyed or threaded to end of the crank shaft (92); this gear drives the two timiu gears (110 and 111).
^The cam shaft timing gears are keyed to the earn shaft (104), one gear and shafl to operate the inlet valves (119), fig. G, and the other gear and shaft to operate the ez- kanst valves (120), fig. H. The gear case is filled with grease and a cover is plaeed over the gears. (On modem engines the gears run in oil.)
Tke inlet valves are placed in their seat by passing them through the inlet valve cap holes (40).
The exhaust valves are placed in position, on the opposite side of the cylinders, in the same manner.
The inlet manifold (45) fig. G, is now bolted to the inlet valve side of the cylinders, and the carburetor is connected to it.
The exhaust manifold (47) fig. H, is bolted to the exhaust side of the cylinders, and is soBBected with muifler (48) at rear of car, by the exhaust pipe (47); see chart 6.
The exhaust valve ci^Ni (41) and the inlet valve caps on the opposite side are now screwed in place — tightly.
The priming cups also known as compression or relief cocks (115) fig. H, are screwed into the exhaust valve caps.
epark plugs (66) are screwed into inlet valve caps or in center of each eylinder se per page 64, but usually over inlet valves.
The fly wheel and starting crank (44-43) are fitted to each end of the crank shaft. By referring to ^g 0-92, the reader will note the end of crank shaft tapers, and ai flange is also turned on this crank shaft. The fly wheel fits to this taper and bolts te l^e flange, as there positively must not be any lost motion.
The magneto (53) fig. G, is bolted in place on a brass base provided for it, on the side ef the engine. An extra gear (which will be explained further on) is operated by the earn shaft and drives the magneto, which generates electricity. The electricity is die- tributed to the four spark plugs (66) at certain periodical times by the distributor cm ■agaeto (122) fig. O.
We now connect our wires through switch (66, see chart 1) to magneto. This switch is to cut off or turn on the electric ignition.
The drcnlating pump (49) is connected to the water jacket of cylinders. The gear (113) driven by the cam gear, drives the pump, and keeps the water in eonstant eireulation, which keeps the cylinders from getting too hot, not over 170 to 180 de- grees Fahr. We now connect rubber hose (51) to metal pipes on radiator (60), see chart 1, and also to our pump (49) and belt up our fan (62), which is run from the same shaft. The radiator is filled with water by unscrewing cap (60, chart 1).
We now connect the gasoline fuel pipe (62) from gasoline or fuel tank (68, see chart 1) with carburetor.
fStaxting the Engine.
We now have our engine ready to run (we will presume it has been fitted to car as shown in chart 1).
We now put the gear shift lever in "neutral" position, so the car will not move when the engine begins to run.
The starting crank is revolved, which turns the crank shaft, timing gear and moves the pistons, (see chart 26). The crank shaft timing gear revolves the cam gears which in turn revolve the cam shaft, and which in turn revolves the cams.
When the cams turn, one of them with its nose pushes up one of the eight valves in one of the four cylinders. (There is one intake and one ex- haust valve for each cylinder.) We will suppose that this valve being raised ii the inlet valve of No. 1 cylinder. As this valve is raised the piston will be going down on the suction or intake stroke, as explained in fig. 1, chart 29, and dnwi in a charge of gas.
*Tkm gtmn sr« timed m shown under Talve timing.
fBm psc* 89 ^hy it is neeessary to start s gasoline engine.
DYKE^S KSTBCCnOX NXMBEK SEVEN.
rif. 1 HhBuumtizu: tte pruicipto •! •ptanc aad ctosiiiff tte tlirottie ▼&!▼• on
Se^ Chart $ »nd r.o:«^ P:«. ^ ard 5i>Uov the rod Indinc ttuoufh the steering column x^' mnd not>f how :t <vcin«fts at i7? , with carburetor.
OiK'r.inir the butt^rlr throttle Tmlre ^i the cmrboretor admits more gas into the ejlindfx, thereby :n<iy«s:zir the speHL Qosing this Talre reduces the 8p<«d.
At tne $aa^e titfte the thn>ttle Wrer is "^dranced.* the spark lever, which shifts the <»nfac: bry^ker on the saci^eox » "adnaced" alaa
If A ti^er wx:i: a .nv/. *v«f« cif i^\a<KK » VMiL tkca the spark \tTtr (see page 60)
Tli^ ob^'? ia 4i\*T.',x^ :ke ^^^Mtt a» tite tk^ottle is epcMd, is to canse the gas to
H44iCTO
L_.
CIS CT^'C^ ^>^cc1ga1i^«NK^
CHART NO. SS-XlemeniaxT Principle of Ooatral of Speed of
motion of the throttle oad $i>ark.
; cxplaininf til
THE GASOLINE ENGINE. Vl
The suction stroke is now completed; the gas which was drawn into the g^der must now be compressed. Just as it is compressedt the electric ipirk occurs at the point of the spark plug and ignites the gas.
At the moment the gas is ignited, the force of the explosion forces the piston down and this force gives momentum to the fly wheel, which will keep the crank shaft in motion until another piston in one of liie four flinders has drawn in and compressed its gas and fired. The cycle opera- tkm explained in chart 29, is repeated over and over again in each cylinder. (See page 116, how a 4 cylinder engine fires.)
Control of Speed of Engine.
After the engine is started with starting crank (self starters will be explained further on), the speed of engine is controlled by opening and clos- ing the throttle of the carburetor which, when opened admits gas to the cylinder. The more gas admitted the stronger the explosive force will be, hence more speed. The gas of course, is admitted through the inlet valve during the suction stroke.
The opening and closing of throttle is regulated by hand by means of the throttle lever (fig. 1, chart 33 and 106) on the steering wheel, or by a foot pedal connected with the same throttle lever called an "accelerator." (See index.)
Oarburetion; the carburetor is connected to the inlet manifold by the inkt pipe, and the gasoline flows to it from the supply tank through a imall brass or copper pipe, called fuel pipe.
Pure gasoline vapor will not bum, but must be mixed with air before it ean be used to develop pressure. The mixing of gasoline vapor and air in the proper proportions is called carburetion. To give the best results, the mixture of gasoline vapor and air must always be in correct proportion. (See index.)
There is a passage through the carburetor into which the air is drawn as the piston makes the suction stroke. The liquid flows to the carburetor an3 is brought into contact with the current of air. The gasoline turns to vapor, ind is absorbed by the air, the mixture being sucked into the cylinder on the inetion stroke.
The quantity of mixture that is drawn into the cylinder during one suc- tion stroke is called the charge. Details of carburetion are given in Instruc- tion 12.
Ignition; when the throttle is being opened and the engine begins to ipeed up, it is then necessary to also "advance'' the time of ignition in other words, cause the spark to occur sooner than when engine was running slow.
A spark lever is usually placed on the steering wheel along side of the throttle lever, which is connected by a rod and bell crank to the contact breaker box on the magneto or if a coil and timer is used, to the timer. (See ehart 33 and 106.)
When the spark lever is moved, it also moves the contact breaker box en magneto or commutator, which causes the spark to occur **late'* or **early" according to the movement of this lever, (chart 33).
The reason for advancing the spark is as follows: To begin with, the diarge is set on fire, or ignited, at the proper time by an electric spark.
The current of electricity that supplies the spark is produced by a bat- tery, or a magneto or dynamo driven by the engine.
The exact instant for the ignition of the charge depends on the kind of work to be done, the speed of the engine, and the quality of the mixture. If die charge is ignited too soon or too late, the engine will not run properly.
68 DYKE'S INSTRUCTION NUMBER SEVEN.
The time of ignition, or instant when the electric spark sets fire to the charge is controUed by means of a commutator, timer or contact breakei which is advanced or retarded by the driver by means of a spark lever on the steering wheel.
We have up to this time supposed that the spark occurs exactly at the moment when the piston reaches the top of the compression stroke. Now, this would be its correct timing were it not that the gas takes quite an ap- preciable time to explode after being ignited, an interval let us say of 1/24C of a second, so that before the gas has had time to burst into a full explosion, the piston, on account of its great speed (suppose it is traveling at 1,50C revolutions per minute), will have traveled about a quarter of a stroke down the cylinder before being affected by it. This means a quarter of everj power stroke wasted.
*Th6 advance of spark; the remedy for this is to make the spark occoi a quarter of a stroke earlier; that is, make it occur when the piston has com pleted but three-quarters of the compression stroke so that the full burst ol explosion and the piston arrive simultaneously at the top of the stroke, or oi top ''dead center.'' This is called advancing the spark.
The retard of spark; suppose the engine is now running at only half th( speed, say 700 revolutions per minute. During the exploding or ignitinf period, which we assumed to be 1/240 of a second, and which remains th( same, the piston, with its speed now reduced, has not time to trave so far, and the spark therefore need not be so much advanced.
Again, when the engine runs dead slow, say at 100 revolutions pel minute, which is slow for a motor car engine, the spark requires hardly an] advance at all. So that we see at once that the faster the engine runs th< more the spark must be advanced, and that the slower the engine runs th( less it need be advanced, or, to express it in a more usual way, the mon the spark must be retarded.
Let it be clearly understood that to ''advance" or "retard" the spark means to cause the spark to occur earlier or later relatively to the position o: the piston. It does not mean that the spark is made to occur more frequently or less frequently.
QaastlOB. — ^How can the spark be made to vary as to the time at which it tak« plaeef
Answer. — ^In chart 33 a device is shown on the magneto which is caUed a ''eoatai breaker." This is usoaUy placed on the end of the magneto armature shaft whie! Ifl operated by the cam shaft. It is nothing more or less than what we might eall rotary or revolving electric switch. For instance, suppose the contact is made o dead eenter, but should it be necessary to advance the spark, the contact breaker ea be tamed, by means of a spark lever on the steering wheel. This wiU cause th •park to be turned on earlier or before the piston has reached the top of the stroke.
Qaeetionw— Suppose I do not advance the spark when the throttle is opened aa engine ie running fast, what thenf
Answer. — The engine wastes say quarter of every explosion stroke, and fails t run to powerfully as it would were the spark properly timed or advanced.
Qneetion. — What if I advance the spark when the engine runs slowly f Answer. — Then there will be a fierce struggle inside the engine; the piston fightia to eomplete the compression stroke, and the explosion, which has occurred too oooi trying to force it back again. And which winsf If the engine is working f^l briik^, the piston overcomes the explosion; otherwise the explosion drives back th pieton, and stops the engine
This is why frequently when an engine is cranked it "kicks back"; the spar has been advanced too far, and the piston can't overcome the early explosion.
QneeHon. — ^How can I tell when the spark is too much advanced?
Answer. — ^There will be a sound in engine as of a hammer striking the top of tl pieton. The engine will be said to knock, and the more the spark is advanced %l louder wiU be the knock.
*Not«. — Lag in the explosion stroke ii ftUo dn* to the electrical apparfttas prodneinf Iho spark, m pagoa 808 and 248. *8eo aUo pat** B05 to 809.
THE GASOLINE ENGINE. 88
Qnestion. — ^And what should make it knock f Does the piston strike the top of ejlinderf
Answer. — We have already pointed out that this is impossible, as the length of the stroke is invariable; neither does it appear that it is caused by a general looseness throughout the parts of the engine, since new engines knock as much as old ones.
A possible explanation, and one which has received some support, is that the charge in the cylinder detonates in much the same way as certain solid explosives. A piece of gun-cotton, for instance, if laid upon an anvil and lighted with a match, bonis silently, because it has all the space to expand in that it requires, but if instead of its being lighted it be struck with a hammer, it goes off with a loud report.
Now, in the ease of the gas exploding in the cylinder, if the piston - is able to ■ore away from it easily and thus give room for the expansion, there is no noise, but if, as in the case we are discussing, the piston moves against the explosion, like the hammer falling on the gun-cotton, the result is a report.
The knocking is not always detected easily by the novice, who will probably con- foM it with other sounds on the car, but when once it has made itself evident, the •park should be instantly retarded until the knocking ceases.
The strains set up in an engine which is allowed to knock may seriously damage eonneeting rods and cranks.
An engine should not be slowed by retarding the spark. If it has been noticed hy the reader during the last few paragraphs that it is possible to slow an engine by retarding the spark, let him at once understand that this is the last method by which it ever ought to be done.
It is not only unscientific, but is also wasteful of fuel, unnecessary work for the engine, and causes rapid pitting of the exhaust valves, the gases passing through them Sb an incandescent form.
The correct method of slowing down or Increasing the engine speed is to shut or epen the throttle valve, which is situated between the carburetor and the inlet valve, bj which the amount of fuel supplied to the engine may be regulated (see illustra- tioB, chart 33, fig. 1). Then as the engine varies its speed slower or faster, the spark ■hoald be retarded or advanced accordingly.
The mle therefore is to let the engine speed follow the throttle and make the spark foUow the engine speed; or to put it in another way, to drive economically, keep the throttle valve closed as much as possible and the spark advanced as far as possible, short of knocking or tendency to knock.
Retarding the spark too much produces heat, see page 319.
Ignition.
Qonsists of a spark plug, a source of electric supply, which may be either a mag- leto, generator or battery and coil. If the latter system*, then a timer or commutator is ued to make contact from the battery to the coil, causing a spark to occur at the points of the spark plug. See fig. 5, chart 39 for an early form of commutator — more modem ■ethods will be treated further on.
The spark ping can be placed over center