tm9-750mediumtanksm3m3a1andm3a2

8/3/2019 Tm9-750MediumTanksM3M3a1AndM3a2

1/82

RESTRICTEDTM 9-750

May 9,1942

!WAR DEPARTMENT

TECHNICAL MANUAL

""ORDNANCE MAINTENANCEMEDIUM TANKS M3, M3Al"AND M3A2


2/82

IT TAKEScareTO KEEP AN ENGINE RUNNING

During recent army maneuvers most engine failure was

due to improper care.

To keep your tank running, be absolutely

sure to:

yldle the engine always at minimum 0 1800 rpm except when shifting gears.

VChange engine oil at 25.hour intervalswhen operating in dust i never longer

than 10 0 hours ullder ideal conditions.

y Clean air cleaners daily.

I Turn handle 0 1air Slter at least oncedaily. Drain at 25 hours.

y Warm engine to at least 80 F .b.lor.

moving tank.

YSloP tank il oil gets hott.r than t90 F .

RESTRICTED

*TM 9-750

TE BNTCAL M.ANnAL}No. S--750

WAR DEPARTl\{ENTtVaSJTIN(l'TON, May 0, ',042,

ORDNANCE MAINTENANCE

MEDIUM TANKS M3, M3A1, AND M3A2

CJTAl"l'ER 1 Op . ti ,ei a mg instru ti 118SECTION I G .encral - P,uagl'apbs

II. Descl"il~tion and tabl~l~~t~d-d~~------------- 1-3T v 'LOPber~tlO:linstructions and cOl :~ r~ ;~ - - - - - - - -4-5

u rication -------- 6-14

V. Inspections --- 15-18

VIT

VI.Gen~r~l care - ; l~d-~ ; '~s -e~ .~~- t i~~==- - - - - -19-24 Materiel affected b ------- 25-32

VITI A Y gas __

C

. . .rmament -.--------------- 33-34IIAPTER 2 O1'O"a1 . ---------

S.

. to llzatl.on instructio --------------- 35-37}X;TlON I G " ns. en ral mformation on .II E ' ,. maintenance

quipment and pecial t 1 -------m. E nz in e an d a c c e s .00 s _~ . , 80ne5_

IV. Fuel sy. tem.,., -----------------

V. Cooling 5yS t r o~== - - - - - - -VI. Clutch --

VII. Propene~-~h~ft------ ------- --- ----------VIII. Tl':111Smision -d-l-ff------:--l----------------

) erentra a 1 .brakes ' < net steerin


3/82

TM 9-7501-4 ORDNANOE MAThTTENANOE

CH.Al'TER 1

OPERATING INSTRUCTIONSParagrapbs

SECTION I, General 1-3

II. Description and tabulated dat,a__________________ 4--5III. Operation mstructions and control :: i______________ 6-14-IV. Lubrication 15-1

V. Inspections 19-24VI. General care and pres rvation 25-32VII. Materiel affected by gas 33-34VIII. Armament 35-37

SEcYI'ION I

GENERALPurpose a nd scQpe_______________ 1Coutent and al'I'angeuleLl _ 2References __ _ __ 3

1. Purpose and scope.-These instructions ar ptrlJlishetl for theinformation and guidance of the personnel of the w-:ing m-mschargedwith the operation maintenance, and repair of tlris llmtrrieL Theycontain descriptions of the major units and their function in rela-

tiouto

the othercomponents of

thetank, as well as instructions for

operation, inspecti n, minor repair and unit replacement,2. Content and arrangement.-Chapter 1 contains informa-

tion chiefly for the zuidanoe of opera till,,. personnel, Chapter2 coutaius information intended chiefly for the guidance of personnelof tile using arms 'ioing maintenance work.

3. References.i=Appendix I l ists al l tandard N omencla ire Lists,Technical Manuals, and other publications for the materiel describedbel' 'in,

SEvl'ION II

DESCRIPT ION AND TABULATED DATADescriptlon _

'1':.lblll"Ii('ti flulll

Pa ragraph.,!

is

4. Description (figs. 0 to 5 rncl.) .-a. The medium tank is anarmored, fulJ-Ll'adt-layillg vehi 1 " powered by a nine-cylinder, air-

(

MEDIUNf 1'A.. xr S M3, 13Al, Ar:Tn M3A2TM 9-750

4

3


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TM 9-7504

FHHJL1~o-Left rear v iew of tank.

4

MEDIUM TANKS Ma, M3Al, AND M3A2TN 9-750

4

cooled rHdial aircraft type engllle located in the rear of the hull. ThellIeuinm tanks M3) M3Al, alld M3A2 diner principally ill the construc-tion o rthe hull. The M3 has a riveted hull j the M3Al has a cast andupper hull j the M3A2 tank hull is of welded construction, All infer-:nation contained in this manual is applicable to all three of the-semodels. All models may be powered by either a gasoline or Dieselengine. The operator steers the vehicle by mCU11S of two leverslocated in the front end of the hull. The vehicle ha-s five forwardspeeds and one reverse, The tank is wired for radio installationund for an interphone system within the tank

FIG n ne .J.-'l'o p v iew o r ta nk .

t., The armor plate is considerably thicker than on previous mediumI :1111,,.;, The armor of the front upper section, cupola, and turretHid,',,, is 2 inches thick; the armor on the sides of the h nll and therl',ul.i. lower sect ion i s 11/:l inches thick,

r: The turret is 60 inches in diameter and can be rotated by meanso[ a hvdraulic system) or by hand, The cupola normally rotatesII' i1 .1 1 1 11 1 'uuret but can be rotated independently by hand.fl.. TIH'If\ is an auxiliary electrical generating system in the tank,

" (lI iS iK I i I I~of a, ge1lE~rating set powered hy a single-cylinder gasoline,"lgll('. This unit charges batteries, heats the engine and fighting1'1 '1IIIJII'I.IIl(m" i, and supplies current to operate turret traversingIIIP",IH! lIiHll1 it lid rud io.

5


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TM 9-7504 ORDNAl'l"GEMAlNTENANCE

Inl- e r-w N

'Ii OJ)w 0


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TlVI 9-7506 ORDNANCE MAIN' l'ENANCE

SECTION III

OPERATION INSTRUCTIONS AND CONTROLS

ParngraphGenera] inform ation on controls________________________________________ 6Inspection before operation______________________________ 7Starting instructions for gnsollne engine_____________ __ 8Start ing Instruct ions for Diesel cnglne_________________________________ 9Eng-i.n tesL______________ _ 10

Operat ing yeblcle___________________________________________________ J]Stopping e n g iJ 1C_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _12Cautiona, -_____ _ _ 13

Cold weather opet tnrns with power on both tracks at all time

(fig, 6).(2) The levers are provided with rubber grips. The lower endsare mounted in . ucb way as to permit relocating th lever l)OsjtjO]1Sto suit the convenience of the drivel'. Both levers are equippsrl withswi tches for firing he rna hine O'uns in the front end of the tan kd. Brolcee-> (1) Seroice b1'akes.-Pulling huck imultaneou 'ly on

both steering levers slows down 0'1' stops the vehicle, depending onhe effort applied.( 2) P rw ki'l1_ q7mzke.-The parkingbrake level' is located on the Ief

side of the driver, back of the steerinz lever. It is a iranemissior;typB bralc and 8ho~ud 11 VB1' be 'used 101' any purpose other thwn'P(lll'lei?1.

e. CZutch.-'rhe clutch pedal is located to the left 0 the transmis-sion housing convenient to the driver's left foot. To perrni shift-ing of gear: ,;, th~~clutch is disengaged by depressing the clutch pedalWhen the pedal is depressed, the ensrine will run jc1le.

10

TM 9-750MEf lIUU 'l'Al"I{S M3, M3Al, A . ! " IDM3A2 . 6--7

f. Gear' sMfti71.g.- hiftinO' of O'ears In th" tr " fh ' . . ' " I all S lIUSSlOl 1 ' 01 ' speedc anges IS accomplIshed by the O'c'U'shift ha nd I . 1 J t . . " the t-i '" ' c eVel ocateCt on the1 u.nS11l1SSlOl1 to re rizht of the driver The P iti f h -hft l' ~ . OSl IOns 0 t e zear

S ~ ever for the various speeds are shown in fizure 7 '1 h b.,sil lf t lev r is e . d . I 1 . ",e zear, . . . qmpI e wi 1 a at h which prevents accid ntal shift-~Ilg into first .speed or reverse, Ths latch must be released by press-il1g tl wn the button on top of the lever before shifting into fi tspeed 01.' reverse. 1'5

4

5

RA PD 2712

FWURE 'f.-Gea, shift POSit ions.

7. Inspection. b.efore operation.-a. By d1'ivC1'.-(1) Cbecks oilI IIii k level, adds 011 if necessary.(~) Checks transmission oil level, adds oil if necessary.( . 1 ) Checks for p.resellce and condition of D.Te extino-uishers.(") Checks for 01 1 or fuel leaks on floor offiD'htino- compartm t(") th t t . 0 '" ' en ..) ~esa s eermg levers, clutch pedal, and gear shift lever

cllll'ndc freely and over he full range.(G) ,Bes that ?attery switch is open and voltmeter reads zero.(7) Sees that fuel shut-off' valve is closed.(H ) Clos s battery switch and sees that voltmeter reads 24 or more

vlOlls.

(D ) 'I'1I1'ns on lights and siren at order of t ank commanderI); Hy, IlIlIk f:olllffn'!'nder-.-(l) Checks final drive oil levels. .

(i) hccks gasoline level.

11


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TM 9-7507-8 ORDNANCE MAL"


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TM 9-7.508-11 ORDNANCE MAINTENANCE

(3) Check for unusual noises in power train and e:ngine.(4) Check magneto swjtcb on 3 positions. .9. Start ing' instructions for Diesel engine.-Af er _PI'estartmo-

inspection the Diesel engine is stnr ted as follows:a. Actuat he decorupresi ion lever to put the engine on decom-

pression.b. 'I'urn the snzine one complete revolution by hand.c. Put Ue engine back on compression.d. Insert the proper cartridge in the cartridze starter and fire. .10. Engine test.-a. As soon as the engine has started the 01]

pressure gage should be watched. If the gag does not indicate oilpre, sure within one-half minute the engine should be shut down andan investigation made. In cold weather when the oil has not beenpreheated, keel) the engine throttled to 800 rpm until the oil tern-perature O"ng reads 800 . . ,b. liVal'lTl the engine up at a speed of 80 0 rpm until the OJ 1 pTe -

sure is between 50 and 80 pounds, which is normal for thi speed.This warm-up hould be 'OD inned for at least 5 minu es afterwhich the speed may be increased to 1,000 l'pm. Should oil pI'essurefall off a an increase 'in peed, the engine should be throttled backfor further warm-up before speed is again increased. A thorough'varming up is recommended.

c. When th oil temperatur gao-e read 0", open th hand throttleO"ntduaHv until the tachometer reads 2,000 rpm and then .lose therhrottle gradually until the engine speed drops to 800 rpm. Checkfor smooth easy I1.cceleration of ellcine , Check the oil pressure., ~

nnd the oil temperatnl'l f\,nd note t 11 8los' of speed when the engineis '.witched to one magneto at n, time. Til> speed should not Iropmore thall 75 rpm below t,lmt attained when operating 011 bothmagnetos.

11. Operating vehicle.-a, Gencr-al.-The drivel' should be thor-oughJy familiar with the :tllllet.ion and operation of al~ the cont.~'olsand instruments before atternj tiJlg to drive he vehicle. Reviewof paragraph 6 should be made in case of doubt.

b. Opemtio11.-With the driver in the driver's seat, the engineat idlinz speed, and all inr trurnents showing normal -eadings, thedrivel" is then ready to drive the vehicle,

(1) Release the parking brake (located on floor to the left ofdri vsr's sea.t),

(2) Dis-engage the dutch by pressing the clutch pedal down to thefloor and holding it down,

14

MEDIUM TANKS M3 M3Al, AN')) M3A2TM 9-750

11-12

(3) Depressing the latch, move the gear shift lever into secondg(,


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TM 9-75012-14 ORDNANCE MAINTEN NeE

swit h on the instrument; panel to the "off" position. Whe11 theengine ha stopped, move the ignition switch to the "off' position,and shut offthe main fuel supply valves.

b. jJi(!8 l engine.-To stop the Diesel engine idl a. 00 rr m for4 or 5 minutes. Put the hand tlnottle in the extreme ciosed position.

Caution.=D not shut. off the fuel l ine valves. If th se valves areshu off, it is possible for air to get. into the injecting ystem, result-ing in air locks.

13. Cautiol1.s.-a. After initial warming, tll tal1k engine must beoperated at appreciable engin speeds (~ ,800-2,100 l'P!n) except forbrief periods at 1500 to 1600 rpm. OlltJJ1ll()US operation of thi typeensrine at. idling speed will shorten the useful life of the engine eon-siderahly by causing increased wear and overheating. On no occasionexcept shifting gears including military ceremonies, will idling of theengine at Jess than 800 rpm be permitted. W11ile the damage to theengine is not immediately apparent, the total life of the engine willb greatly reduced.

b. The enzine should be idled at about 00 rpm until the engine oiltemperature gage indicates a temperaturevise of about 100 F. beforeoperating the vehicle at full speed and under load. This is necessaryto prevent damage to the engine workillg parts. Avoid rapid move-ment. of the accelerator. since this causes a spray of O'asoline to be in-jected into the cylinders. Thi gasoline washes oil from the cylinderwalls and cause. excessive wear,

. Do not. attempt to star the enzine by "towing" 01' " cast ing" thevehicle, To do so may cause serious damnze to the engine and trans-

mission, To star the engine, USe the electric starter or hand starter.d. Care must be taken not to place any object in a position where itwi11block the flow of air from the cylinders, Blocking off any } linderwill cause overheating and preignitiol1 in the cylinder so affect d.Care must also be taken not to block engine oil cooler.14. Cold weather operat ion.-J 11 ont'l' hIlt the ank engine may

be itarted and operated with a minimum of difficulty in very 'oldweather it will b necessary that the following precautions be takenprior to startinz.

a. Before stopping the eruzine in cold weather, pull out the oil dilu-tion valve operating button, which is located under the engine oil tankand hold the valve open the a1propriate rium bel' of econds , dep ndingupon the anticipated temperature (see char in pur. 17). The oldermodels have manually operated alves: later models have a solenoid-operated valve whi his contrulled b.' a button on the ins trument [JRneLIn case the valve is manually operated the engine compartment must

1 6

MED! ]\ -{ TANK M3, M3Al AND M3A2TM 9-750

14-16

11(1~lppl1 ed and the valve checked to make sure .it is dosed. Following:I ~hllt-do\i',rn 011 diluted oil the engine must be operated at least 20nuuures when next. started to insure the evaporation of the gasoline inI JH \?il. The oil dilution line must be disconnected a all imes exceptdunll'" weather when dilution is absolutely necessary U11dthen the oild i lu tion sys em must not be used except when .old startine onditions:1I'e anti" i pated,

b. If clo ed buildings or shelters of any kind are available the tankshould he placed in thesa shelter, and some method of heatinz provided.'1':lke due precautions against fire hazards from leaking fuel 01' oil .

I.' s~ld\ sh~lters areBOt.

available tanks which must be kept avu.ilnblajol' Immech:tte use ma,y be ~ept Warm COli iderably above prevai1ing1!'lIlpel'atul'es by coverIng WIUl a tarpaulin.

n. 1 -\ short tim~ .before starting the engine it hould be heated bylIWans of the aUXJ)ulI'Y geneX'lltol'set accordinv to the directions zivenin section XII, chapter 2. '" b": Under extremely cold conditions it may be necessaty, in or-del' to

:l1


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TM 9-75016 ORDNANCE MAINTENANCE

b. The handle on the disk type oil filter (fig. 10) should be turnedone complete revolution (in either direction) ead~ day. !f exam~a-tion of the oil hews any appreciable arnoun of dir or discolorationthe filter hould be removed and exchanged for a new one.

RA PO 4232

lrH1URE (I.-Engne o il gya tem.

c. There is one breather connection, from the nose of he engineto the lef t ai l' intake pipe, to provide necessary v nting of the ngine.d. The oil tank (Iig. 11) is filled through the filler hole on the tank.

The cap for this hole is fitted with a bayonet gage which indicates

18

MEDI M 1'. NK M3, M3Al AN'O M3A2TM 9-750

16-17

Lil t ; )oil level. 'I'o druin the system, remove the cover plate locatedbelow the hull floor pla e directly under the oil tank. This permitsrvruova] of the drain plug.

17. Oil dilution valve.-a. This valve is used to permit easierli ,lIrlin a of tIle engine in cold weather by mixing gasol ine with the(1lll!inc oil. Before stopping the enzine in cold weather, pull out the

DRAI~

l~lOllm, lO.-DiSk tYJlP.oil !\I!el.

I 'l l 11'1' "iI",':d,i I I_ ! ! ;button, which is located under the engine oil tank(Ii" I J ). TIl(' button opens the ga aline valve and allows ga cline1 0 1urix willi 111 ( ' oil, The period of time to hold the valve open will.!")lI1111 Oil 11i(' 1.(',lllp'raLurc. To determine the period of time to1, ,01011111 ' \'1111"(' Opl'11 estimate the lowest temperature anticipated at

IIII' I , ':-;.1 l"~i 1)(' sl :1,r( i IIg. F'iud this temperature in the table given

19


11/82

TM 9-75017 OHnNANCE MAlK'l'E~ANCE

1"!GliRE n.-Ol tnnk aud coolur.

20

MEDIUM TAl\~& M3 M3Al AND "N13A2

T!VI 9-75017-18

1,('low and hold the oil dilution valve open the Jength of time in-

dicated opposite this temperature. in the chart.'l'emJ)rr",lure

( 0 F.J

+30+20+HI

{)

-10

-20-30

Dilution /.im6(8e('(i11


12/82

TM 9-75018 ORDNANCE MAINTENANCE

OiH. ond fin.' Drive EO 3

[See,~~I~) I.~~t~~~:~f1Ir~ Dr;"'", brei,. PIJI ,

LlM,.,ulund .. ,\,d

O i 6CTU11 i JL) , .n r r P l rM l.!L.;...dI".I,,"-I1

TUlllJIII:iHIoIID,,,v_fIIPIIiI1t..tA1.4v!!u.......

--IEY-IlItlnills. lw l . .. l i

'O~;MOil 5"".1$(1-

"~~ii.!L::~:...H...IIJbv... UF.1

D - D . 11 J''.4- UCialiu1-I,(IClO.1l1t.l'-l.OIlIl ,,(I

e._kl:l.n,c.r~ ..!;IalCa."

ClItd:5IM"...l lrCt. . uQ,

S.r.le-ed F'rom EngineCompartment

C lu tc h T h, ow." , Yol . B '9" CG[A l ia . . ., ,&1Dit . . . . t . r 1Hi~1iu.1 EO!"tiI:".~ko.ot.... ~r.1.l..,.t

la"~Io~)

A ir C le an er s EO!w:)....-!.I~..,.1 do .....:I , U" ,- O . .. ~ u .

~N~. '1

Sci.lin. 1.1 '9 ' . ' 0 'ISAE 1 11N. . .I_DI t(..t i ....

DiH. "nd F ina lO l i 'l l! !

I e-eTabfe)fH lb I )F_I , . . dllo"'.,~JlF~a~ Dr"~ D,JlI;.rt prill,1 ' I .K . .~o.d w:llll.r h~I ' 1

Se.vlc ed from Fightl"9Compartment

CG G , Shil t Sh. lt

EO P"~n9 Br.le (0;1hoi.!

E O U ni"en .o JJoint l o N p t. . ,Ir,Ul".l

EO Uni ' /e1$4' SlipJoin i lHot.."l[p~!t

EO UniVeJ1i61jOlnt [Nco' . 6~fiUJ~d

EO E ng ". O il Tan I { S T. bl .1I~a~. 11 l"Fillu.p, ~.r6~.LttU f

Serviced Frotn Ensinec.ompartment

D EO Clu tchS leeve (1 oilhol"l

Oif Fn~r,j N 1 l 1 J o71

EO Ai r C lean D "(1d)--'~I"".J&.""t1 "I;o!il..._I""'O~. ~1~trlrNa!. II

f.~ fiI1U

IN",!. I'C D

. t k M3 and MaA1 (Ordnance Depart-12 -Lubric.1.tioD instructions tOl" medtnm "~' S . . . . . Sl\'L G-I04.)FIGURl'l '. .a., No 1 located ou uurue plate instdc figbtlllg compartment,nent sca,ting ~(!IIlnd Shield hinges, p .. ephole protectors, pistol port111\'1'1 , ~h~HI' In!dtf'~, C.ontrol rod pin: Iln(l ]pver bushhlgs, erc., wtth p~t'Kjue oi l S&1 .E 304 , . 1\ "rlfl Illfl.,....

II> / '11/11/1< /0 Itt' IU/)Ii(;(ltcrl (11. N11Ie of ,'ngillc """"01/111 tor period,,, .j""'P~Uon.-Clulcht1111 . ' ' 1 I 11 . 11 I~ u r lC l eluich hub bct1. -lng.

I I I'''/IIIN I" ~" III/)r;o(l/ , ,1 by ordnoncc "",';ntenrJ.iJcc per801r.1


13/82

TM 9-75018 ORDNANCE MA1NTEr\ANCE

T U RR ET j -I YD R A UL IC D R !V ~

~-:-------- !f.. HO Hydr.!l.uJi_~Oil T.n~ ~F.'I~ . ly.s lI C ' o I < . t IIIT~ .MII r ~U ~ R.' . ._ . . . . .'IlC.p.~;]~ I) ~,f

'rUJic Tr~vi!!-nr.n9 G 1::~rJ and CG 1/4R.~ . . :=k

-KEY- --L u br lc u t . .

C . :J I. 3 0 M "t : h . i . n eG u n S . .. ..iveltL;a.lnr1ul~~9Ii.ai.1 ..14..".1

l~rFu 1i;~tJtl.co--CLIIJJ~GI.'!~a. tIo Lbt1p. . l~~ F.INItoI t~'bltr. u' F.~

tfO--+lr~r.wllt 0.:1

CUPOLA

t U Inr ,."mlimn tanks Mil audi\I:~AI-C("tln 1ed,FIOUl!f:. 12.-LullricaUoD illS [uc ous " _ H

24

MEDIUM TANKS M3, M3A 1, AND M3A2TM 9-750

19'-"-20

EC'rrON V

INSPECTIONS

I "'I'P' '! (l' _

I' "SIle{'U0)1 berore ouera ttou _

Parngmph________________________________ 19

201I,,~LJI'r'ti()l, c111l'ing 0llcl'atJon_____ 2111'''1'' "'1 ion at hal L _ __ __ 22

I , tSP"" r; 0 n arter opera t lou ~ _I',"';, .(1c i nsjiectlon _

__ 23

24

19, Purpose.c-es, To insure mechanical efIicieucy, i.t. i s necessaryIll:! I, t.anks be systematically inspected fit intervals in order that

dd\,\'ts rnay be prevented 01' discovered and corrected. before theynslIl!. 'in serious damage,I,. Cracks that develop in castings OJ' other metal parts may often

II" dd(,cted on the completion of il run by an examination for dust.1111Ii 0 i1 d eposi ts aroun d the cracks,

t', ,suggestions toward changes in design prompted by chronic faiI-111\1 or malfunction of a unit. 01' group of units; pertinent changes inI'IIHI'I'et ion or maintenance methods; and changes involving safety)nllil'il'II{'.Y, economy, and comfort should be forwarded to the office ofIIIP CiIIl.J't o rOrdnance, through technical channels, at the time they"""I,lop, Such action rs encouraged, in order that. other organiza-II"'IH 11I;IY profit thereby,

20. In spection befo re ope ration.i--c, By driv13r,-(l) Checks1111111111 ,h-vel : adds oil if necessary,

(:.!) Checlrs transmission oil level; adds oil if necessary,(:1) Checks :for presence [mel condition of fire extinguishers.( I) ('IIN'ks for oil 01' fuel leaks on floor of fighting compartment.I:' ) ,""I'I'S that steering levers) clutch pedal and gear shift lever

"I ""'11111 Ireely and over the full range.II:) ,""('('S tirut battery switch is open and voltmeter reads zero,Ii .) Nt't'f; that fuel shut-off valve is closed.I H) ('[()S('S battery switch and sees that. voltmeter reads 24 01' more

\ , ,11 . . .; ,

I II ) TII'IIS on lights and siren at order of tank commander,I III) Illsjl(\cts to see that hydraulic brake booster pnmp is deal' of

t' III' 1110'I'.~ IIn list pi pe ,I II) HI'IIIOVCS inspection plate 1 1 1 1 ( 1examines "tee" connection of

10 1ill", 111'1 'Hll'!' system, located forward of engine for leaks,t I:!.) .I'~xnlilines all hydraulic lines of brake booster system for

t'lllIn.II~' 1IIIOJ I"ose anchor clips,( 1 :1 ) t 'h ock s lev el of swnp tank of brake booster system,

25


14/82

TM 9-75020-22 ORDNANCE MAlNTE ANCE

7;. By tanJ.~eounn asuier> (1) Checks fin a 1 drive oil levels.(2) Checks gaso line level.(3) Oils throw-out bearing.(4) vYnl.ks around t.ank and illspects-a) For gU::loline 01 : oil leaks underneath tank.(b ) That outsid accessories pioneer tools, tow cable, shackles

and shackle pins, e '. are present.c) General .ondi tion of S[ rockets, bogie wheels, spring guides)

gudgeons track supporting rollers, and rdlers. ( l ) Tracks for wear. tigh nes ) and tension; end cOl1"tlections Tor

wear.(e ) Condition 0:1 'wedges and 'we,dge nuts.(f) ndition and tightness of grousers if us eel.(5) Turnsengine over by baud about two compl te 1:evolntions to

clear cylinders of' hydrostatic lock.(6) C~U1StlS driver to operate all Iights nnd rhe siren.(7) Sees tl1nt ammunition, flags field eqllipillellt and rations,

when carried, are properly loaded.(S ) Checks e l eva t i on and tru v e rs in g o f v e h ic leweapol1s.(9) Ter ts turret nIH] cupola to ~ee that it 111))' freely by hand

and that locking and t raversing mechruu: II func ion.(10) tart.' Homolite zonerator and then op 1'[1. tes turret by

power, hecking for sas of opera tion,(11) Has radio and antenna checked for operation.21. Inspection during operation.-a.. During operation the

driver .hould be alert to detect abnormal Iunctioninu of the ngine.

He should be trained to detect unusual engine sounds or noises, He,;hould gian :e frequently at th instrument 1 anel gage to see if theengine is fllllctioning properly. An unsteady o il gage pointer indi-cates low oil pressure provided that engine :-p(ed is fairly const~lJ1t.The s eering mechanism mu t be che ked for cl -arnnce before engage-ment, intensity of pull requi rcd for braking, pte.

'h . Only un ler exceptional eircurnstances should a tank he operatedafter indications of trouble have been observed. When m doubt theengine shouldbe stopped and nssistance obtained, Inspection duringoperati n II Iplies to the entire vehicle and should be emphasizedthroughout the drix ing instruction period.

22. Inspection at halt.-a. At each halt the operator should makea careful in pecticn of the tank to determin. its O'enenu mechanicalcondi ti on. Minor defects detected during the march together withiefect discovered at the halt should b corrected befor resuming themarch. If the defects cannot be corrected during th halt, FrapeI'

26

II/TEDIUM TANKS M3, M3Al, AND M3A2

TM 9-75022-23

II i."pw.;iLion of the vehicle should he made so that unnecessary delayIIIII.\' II( ' uvc ided andmajor failure prevented,lr . A suitable general routine is as follow:II) .\ 110W the engine to run a short time itt iclli n 0' speed (800 rpm) .

r,is! I'll fol' unusual noises, e(~) Nule uny unusual gear train noises.(:1) Clll'l'k fo r tran mission and differenti al oil leaks inside fighting

( 'u11I pn 1'( mcnt,( ,I ) Nole ~teel 'jng adjustment ,~;I) If baL'l'cb 01 1machine guns have worked loose, they sll uld be

:111.1",,11'(1.

Iii) Through the opening in the bulkhead examine the clutch throw-0111IJ(';ll'ilig" aud oil their outer race.

17) Wulk around the vehicle, looking carefully fo r fuel 01' nil leaks.(H ) H,('Jl\()vedirt from under the rack support railers and from be-

t II 1'1'11 Ilog:il' wheel arms,.(~I.) Examine tracks for adjustment and lor worn, loose, broken, or

InIf 'ill)g: parts.

( I (J ) 1~Isped ht~ll and fittings for missing, worn or 100,'e parts,( I I) J ('("1 stecl'mg bruke hous in es and gear case for evidence of

"I I'l'llI':1I illg. -

( 1~) ()11(:'.11\lool'S 0 engine compartment and inspect 01' loose parts1;0,,''' '1I)f1r11~di(J.n and leaks. '

( 1:\ ) Illspl\ct the l iO'hts , i f t raveling at night with J ights.I 111 ( 'lu '. l'k the amount of fuel in tlle tank( 1,,) Wipe> all windshields and vi 'ion devi es. On not use an oily

'Ii dlll.\' I'ilg.:J:i.. nspection after operation.-A the conclusion of each day's

III'I'I'IIII~III. [,he' tank commander should cause an inspection to be11111111, ,11111 it I ' to that made at Jmlts but more thorough and detailed,I I 11101"' :1 (, ,


15/82

TM 9-75023-24 ORDNAN E M.Al1TEN :NeE

h. Check and clean air cleaners during extremely dusty operations.i. Inspect light, siren, and winclshie~d wipers. Check for loss or

damaze of exhaust muffler and accessories. .j. I~spect the sighting an i vision de:ices f~r breakage.7 e.Inspect zuns and mounts for defective performau?e.l; nspect guns, sighting equipment, and nccessories to determine

whether covers are properly installed. .m: Inspect ammunition and sigh iog compartments for cleanliness

and orderly arrangement. . . .n. Replenish oil fuel, and ammunition,

o. For continuous operation U1 hot weather, battery water must bereplenished about twice a week.

'P .Check operation of turret.q. Test auxiliary generating unit.r. Check brake booster pressure gaO"e,which should read above

1,450 psi.s. Check oil level of booster system ump tank.t. Check:entire brake b os er system fOI" visible 1 aks,

b 11 . .' c ovu 0 parts at brakeu, Remove empty sue s, tW1 S, etc. nom m I",booster control valve, ." .

'D. Check tightness of steering brake bands and action of hydnwhcboosting by Ol)erating brake levers. . ..

24. Periodic inspection.-The following periodic inspeccions aleprescribed:

a . Datily check.

By "(~rivelTransmission oil level.Gasoline shut-off valves,Battery switch.Fire extinguishers.Engine tools.teering levers.

Clutch pedal and free travelControl linkage.Gear shift lever.Interlock retaining screw arid

plug.Primer.Starter.Accelerator.Instrument readings at 1,000 rpm.Ammeter.

B11 t(rnlr; com:mo.'1ulllr"

Amount of fuel.Engin ' oil 1 vel.Turn over engine by hand.Pioneer tool.Tow CtLble.Shackle and shackle pins.Guides and O"udgeons.Bogies.Springs.Idlers.Track supporting rollers.Sprockets.Trades.End connectors.vVedges and wedge nuts.

Gronsers.

28

MEDl M 'rANK M3 l M3Al) AND M3A2TM 9-750

24

By tank: comnuuuier

Equ ipmen t.Turret, por ts, etc.Lights.Siren.Shielding.Ammuni tion.Weapons.Gun mounts.Oil leaks.Fuel leaks.

Air horn connection.Engine noises.Is tank clean ~Turn CUll.O filter one turn.

l). liO-h01/11' clwclc.-(l) Remove, clean, and test spark plugs.(~) HPill eve 111agneto breaker point hOUSiJlgS and check points.1;\) HCll10ve carburetor strainer, bypass strainer and oil pump

By drfV61

\' oil IlIntCI".(Ji l p n-ssm'e gage.'I'r-ruperut.ure gage (c ug i n a

wn rm}.

I Ii IPH : '11800 rpm.~Jllgit'LIIS and plugs.( 'Ill k II n-lca e bearing oiled.'I'rnusruission oil petcock.11:lIgilll) noises.' 1 ' 1 ' 11nsmissicn noises.

\.!'.'l"ll.

I I) Check carburetor mounting bolts, air intake pipes for loose11 " ' 11 "r-Iumps, leaks, or cracked carburetor elbow.I fl) Check engine for any loose parts, nuts, bolts, l ines, connections,

.1 , ' .1(' ,) 1{( 'lI lOveany dirt accumulated under two lower cylinder heads.(7) Uhcck carburetor throttle controls for missing cotter keys and

II . I' 1111 ( 'rill iOB.

( H) ('lm'le 0"0vern or for operation and rpm (2,100).III) ('lw(1\ oil and gas line connections shut-off valves, etc. for11 " i I ,Illrl)lIghont.

(10) i < , 1 "111 ( )Veair cleaners C07nllletelyand clean.( II) ('II(',ek clutch operation and clutch release beariusrs :for proper

,1"111,1111'1'.

( I" ) H(PI':I t daily check steps and make our driver 's report..' !rlf/ hour oJwc7r;.-(l) Check all items on 50-hour and daily

11. ,'h~. Thoroughly check lubrication of the vehicle (follow lubrica-111111 , '1 1 1 11 '1 , ).

I 1 1 Ii I" I1III V{' engine from tank. (Fo llowin g paragraph 59, break/1 I "'1/',"'/ ; / IJ ' .~'IIJ/w're 8 pecified --fo llo w a ll step siln order.](:1) H\!I10\'( rIisassemble, and clean CUllO oil filter.(I 1\,1'1[111\'1' 1l11d olefin oil nr p strainer.!,,) 11 111 : . 1 ,II iI roulcr and lines.

28


16/82

TM 9-75024-26 ORDNAN E MAlNTE, A.l\TCE

(6) Drain oil tank and uemove hopper from tank, Inspect forsludge and dirt, Clean,

(7) Disassemble clutch clean it, and check for cracked or wornplates.

(8) Remove radio operator's seat, tunnel inspection plate, and tun-nel cover (rear). Break slip joint and front companion flange boltsand remove propeller shaft,

(9) Check joint in accelerator linkage. Clean out tunnel. Checklines and linkag ill tunnel.

(10) Clean fighting and sturine compartments and trace cause ofany excess oil

(11) Remove rocker bo x covers and ch ck nJI valve clearance .

SJ


17/82

TM9-75028-31 OR.DNANCE MAIN'l'ENANCE

spraying. It will brush satisfactorily as received or after the addi-tion of not more than 5 percent by volume of thinner. It will bedry enough to touch in 30 minutes, and hard in 5 to 7 hours. Forspraying, it may be thinned with not more than 15 percent by VOlU\lH'~of thinner, Lacquers must not be applied to the primer, groundsynthetic, within less than 48 hours ..c. Primer, synthetic, rust inhibiting, for bare metal, should be used

on metal as a , base coat , Its use and application are similar to thoseoutlined in b above,

d. The success of a job of painting depends pa,rtly on the selectionof a suitable paint, but also lUTglliy upon thB care used in prepttring

the surface prior to painting. All parts to be painted should be freel'rom rust, dirt, grease, kerosene, oil, and alknli,and must, be dry,29. Painting metal surfaces.~If IYH'lta

C

) parts are in need of cIpan-ing, tIle), should be washed in a l iquid solut ion consisting 0:1 '1 f2 pou lidof soda ash in 8 quarts of warm water, or an equivalent solution, thenrinsed in clear water and wiped thoroughly dry. Wood parts inneed of cleaning should be treated in the same manner but the alka-line solution must not be left on for more than a few minutes and thesurfaces should be wiped dryas soon as they are washed clean,When artillery or automotive equipment is in fair condition and onlymaned in spots the bad places should be touched with enamel, syn-thetic, olive-drab, lusterless, and permitted to dry, The whole sur-face will then be sandpapered with paper, flint, No.1, and a finishcoat of enamel, synthetic, olivB"drab lusterless, applied and allowedto dry thorough ly before the materie] is used, If th e equipment is in

bad condition, all parts should be thoroughly sanded with paper,flint) No.2, 01' eqllivuJent, given a COlLt of primer, ground, syntheticand permitted to dry for at least 1611Our5, They will then be sand-papered with paper flint, No. 00, wiped free from dust and dirt, amla final coat of enamel, synthetic, olive-drab, lusterless, applied andallowed to dry thoroughly before the materiel is used.30. Paint as camoufl.age,~Calllouflage is now a major considers ..

tion in painting ordnance vehicles) with rust prevention seconds ry,The camouflage plan at present employed utilizes three factors:colo!' gloss, and stenciling. Vehicles are painted with enamel, I;yn-thatic olive-dra,b, lusterless, which was chosen to blend in reasonablywell with the average landscape,31. Rem.oving paint.~Atel' repeated paintings, the paint may

become so thick as to crack and scale off in places, presenting anunsightly appearance. If such is the case, remove the old paint byuse of a lime and lye solution (see TM 9-850 for details) or remover,

32

MI I:DIUM TANKS M3, M3Ai, AND M3A2TM 9-750

81-34

lIui. ll I. alld varnish. It is jmportant that every trace of lye 01 otherpill ~II' I' ITHlver be completely rinsed of f and that the equipment be1,,'rllld,ly dry before repainting is attempted, It is preferable thatIIII' IIHI' of lye solu~ions be limited to iron or steel parts. If used onI~ ! lud, l.hc lye sulution must not be allowed to remain on the surfacel!'r HI(lre ,than a minute before being thoroughly rinsed of f and the. ,ud: l l 'n clVlped dry with rags. Crevices or cracks in wood should beIii Ii,:I with putty and the wood sandpapered before 1'e6111shinO'., The,111'1 II(( s I h IIS P reparad should be pain ted according to directions inI III I'lIgl'!tVh 29 ,! a~.. Pai~,tin~ ~ubri?at~ng de~ices,~Oi1 cups, grease fittings, oil-111 . 11 : -; .Il,l\([, ~aml!ttll~bl'lc.atmg devices, as well ttl; a circle about three-I 'J II ril l s uf, an inch 1n diameter at each po int of lubrication w iI I be1'111I1.lodWith enamel, red, water resist ing, in order that the' ma be11'lllllly ioca.ted. Y . Y

SE


18/82

TM9-75034 ORDNANCE MAI:NTENANCE

(2) In the event ammunition has been exposed to gas, it mll.s~ bethoroughly cleaned before it can be fired . . To. cl~a.n a.mmUl~lbon,a Honcon-osiv>decont.aminating agent or, If this IS not available,strong soap and cool water should be used. After cleaning, wipeall ammunition dry "lith clean rags, Do not we dry powd:-~eddecontamilnating agenl (chloride of lime) on or near ~~~Mnsupplies, as flaming occurs through the use of the chloride of limeon liquid mustard gas.

b. Decpnta'l'l~inat'i,on.-The following measures should be taken forthe removal of liquid chemicals (mustard, lewisite, etc.) frommateriel For all of these operations, a complete suit of impermeableclothing and a service gas mask must be worn. Immediately afterthe removal of the suit a thorough bath. with soap and water. .(preferably hot) must be taken. If any skin areas have come 11 1contact with mustard, if even a very srnal] drop o rmustard getsinto an eye, or if the vapor of mustard has b:en in~al~d, it isimperative that complete first-aid measures be ~lven wtth~ 20 ? I"30 minutes after exposure. First-aid in structions are given 111TM 9-850 and in FM 21-40. Garments exposed to mustard gas can bedecontaminated. If impermeable clothing has been exposed to vaporonly, it may be decontaminated by hanging in the open air, prefer-ably in the sunlight, for several days. It may also be cleaned bysteaming : 1 ' 01 '2 hours. If the impermeable clothing has been co~-taminated w:ith liquid mustard gas, steaming for 6 to 8 hours willbe required. "Var ious lands 0 1 'steaming devices can be improvisedfrom materials avn.ihble in the field.

(1) COlnmene !:ly freeing materiel ~f d~rL thr?ugh th~ use ~fsticks, rags, etc., which must be buried immediately after thisoperation. .. (2) If the surbce of the materiel is coated WIth grease. or ~eav!

oil, this grease or oil should he removed before dseoatamination ISundertaken. Dry-cleaning solvent or other available solven~ for ~llshould be used. with razs attached to ends of sticks. Followmg tins,o ..decontaminate the materiel with bleaching solution made by mixmgone part decontaminatil1g agent (chloride of Iime) with one partwater. This solution should be swabbed over all surfaces. Washoff with water dry, and oil all surfaces.

(3) All unp~inted metal parts and instruments exposed t.omustardor lewisite zas must be decontaminated with a noncorrosive decon-taminating '"'agent, mixed one part solid to fifteen parts solvent(acetylene t.etrachloride). If this is not available, use WUTm \~at:el"and soap. Bleaching solution must not be used" because of Its

34

MEDIUM TANKS Ma, M3A1, Al."VDM3A2TM 9-750

34-35

!!lIToH .ve action. Instrument lenses may be cleaned with lens tissuePUp('I' only using a. very small amount of ethyl alcohol. Coat all1 )11 1 : 11surfaces lightly with engine oil or sperm oil.

( I) III the event that a decontaminating agent (chloride of lime)I' 11011, uvailable, materiel may be temporarily cleaned with large\ ul 1.1.IWS of hot water. However, mustard lying in joints or in1 , ' 11111"1"or canvas web is not removed by this procedure and thusI\" j II n~mai 11 u constant source of danger until the materiel can bel'l"ol)t'rl'y decontaminated. Al l mustard was11edfrom materiel in this111111111('1' lies unchanged 011 the ground, necessitating that the con-111111 i11 : 11ntl area be plainly marked with warning signs beforeIIIIII 1111()111110nt.

( fJ) TIle cleaning 01' decontaminating o rmateriel which has beenJ '0\ 111.11111 im~ted with lewisite will wash arsenic compounds into the"II, IH'lsoning water supplies in the locality for either men orun uuu ls,

(Ii) L('athel' or canvas web that has been contaminated should110 , 'II.il)iJ(l(l thoroughly with bleaching solution. In the e-vent this11"1 ' 1111111 ' 111 .:is insufficient it may be necesaary to burn or bury such1I11I1"I'iu I.

, '. 1 .1 1I.lw ense 01 vehicles that have been subjected to gas attackII I1 II 11m l 'ng ine running) the ai r cleaners should be serviced by re -111'1\ IIII~ t he oil, flushing with a dry-cleaning solvent, and. refillingII IIh jill' ]ll'opl~r grade of oil. Instrument panels should be cleanedIII II,,, NililIe manner as outlined for instruments. Seat cushions I;hatIIII' ", 1111.11111 i II nted should be discarded. Washing the compa rtmsnts111'1I11I1J..:1 d.I' wit.h bleaching solutions is the most that can be doneIII 1111 ' 111 \ 1


19/82

TM 9-75035 ORDNANCE MAIN'l'EN ANCE

component parts of tl1f' tank. For more detailed instructions onoperation , care, and preservation of the guns and their mounts,refer to the various manuals for the guns (see appendix). Theammunition stowage chart gives the location of ammunition, Alsosee figure 13.

I,~, 'l'eu 100'r0l1 nrl Ilel ts " , , -1 ..30 fl In muni tton,1. Drfvers S"U t,2 , Ra di o 01>e.1"tO,.'. seat.3 . 75, nl ln gu nne r's s en t.4. 37mm gunner's sea t.

5. 37 -mm gun l oa dc rs s ca t.6. Tan,l;;:commnnder's sent.8. Cal .. KOmaehine gun,9, Cal. . 30 macnlne gun,

10. 37mm g"n.11. 7,fjrnm gun.12 . 2 ca l .. 3 0 m"-c hin e g un s.1 3. Pr o t ee tOS~Q pes. 25,14. 51 rounds 37 -mm ammun tuon ca rrle~ in 26.

j n. 20 rounds a7-Hnn : ,uni llunlt ion . .~rL 'I~nu tr'PIl 2!)O- nm nf! bel ts contt ti llLng 225

rounds C~~ll. _:~Oaru In lin ilion.

2251. ~"'lO ~!)O~rond 1u~1S contn,j uinground" cnl , . :10 ununuu iucn.22. Twenty!h" 100- 1 _I 22[ '-Tonnd bel t J _

II) 1OO-ro und belts _

:1 22!)-round Ilclw , _Ii InO-I'mlnd belts _

1()(I-I"(JllIld belts _I I :22~i-I'u und belts , _

:!:~ 2!i-rou lid belts,

7,200 rounds:21) InO-rOil I] d bel ts,

2,000 rounds

9,200 rounds

~2

20 _

51 _

13

11

179

Box rear 10ft corner (17, fig. 13).Box Tear right corner (24, fig, 13).Box 011 ' floor, d irect ly behind radio oper-ator ( 19, fig. 13).

3 rows mounted on racks 011 ~ul"ret wall(14, fig. 13),

Mounted on rack rear wall, fighting com-partment (15, fig. 13).

Above Homelite generator or) rack rearleft figlrting compartment (16, fig. 13) .

I III I., 20 r;OLI'OlOd magazines , __ Real' right corner rack, top 37~mm box.2 f iO -1OIJ 11d magaaiues., ___ In guns. 1 flO- round magasluos; ___ Box, left of radio operator.

I,:{{)O rounds.

I III In tray of cal. .30 gun feed box alongsidegun (21, fig. 13).

Turret platform.In combination mount .Box behind radio operator scat. with 37-

mrn su pply (18, fig. 13) .Beside propeller shaft boustng.Box over propeller shaft next to 75-mm

supply,Above propeller shaft housing.In trays under radio operator's sea t (20,

fig. 13).Above propeller slmft. (forward).01i tool box.

37


20/82

0..

~ !ba::: a: : f'),j (:} I>-'r

ir lt.:

TM 9-75035 ORDNfu~CEMArNTENM~CE

"= -:.-'":;l'-;

:;

'"'":; :,~I-

I....'""..Je; . ;

...J..J

W 1 tlhi :t:3; ,3:,

~ 02:

Z,

'l:t


21/82

TM 9-75035 ORDNANCE j\lUl.Dl'l'E"' ANCE

FIGUltE 10.- 'aL .30 bow guns.

4 0

TM 9-750MED'IUM 'l'AiTI'::S M3 M3Al, AND M31\2 35

(:J) 'I'ho ~U1l11el' sits in a seat on th left side of the gun mount.l i l t . ; I Csi t ion in relation to the gun does not change when the glillI ! 11'\':11(:11 or traversed.

(:1) ' 1 ' 116 '75-mm gll l l is traversed 15 in each direction by the J O ' N 6 r111I11t1",11('01 immediately in front of and facing the gunner. 10 k-II I, c' III riling of the handwheel traverses the gnn toward the)' i


22/82

TM 9-75035

hung one of the caliber .45 submachine guns M1928.Al for usethrough the pistol ports of the tank. Refer to figure 13 for ammu-nition stowage.

(7) The 75-mm gun can be fired manually or electrical~y. Thegun is fired electrically by depressing the button located m front

]'lG(lRg 18.-ProtectoscDpe.

of gunner, above handwheel, (See fig. 14.) The gun is fired man-ually by depressing a button located in the traversing mechanism,

b. Turret guns and moumi (fig, 15) .-The guns located in theturret consist of a 3'7-ll11ngWl ~f5o r M6 and a caliber ,30 machinesrun M1919A4 which are mounted together and move as one unit,1 :> ' ~The guns are traversed by turning the whole turret assembly, usingthe hydraulic system 01' by hand,

NOTE.-The gun tubes for the 37-mm gum; 1115and M6 are nut to be lnterebauged,

42

MED'IlJM: TAi""fK.& MS, MSAl, AND M3A2TM U 71,u

an

J.'q[, operation of turret traverse see section XIV,. chapter 2. 'I'll,..'.["I'H t i1Ig' handwheel is located on the left side of the 37 - 1 I l . 11110:'11'oIil'I,'I.Iy in front of the gunnel', Turning the handwheel CUIIIJI.(II'!'II wi( 11' l",'(\ depresses the guns. a maximum of 7 and 1'\1n i IIgrI,j('li:wise elevates them to a. maximum oi60. The guns anli"I,t!

LIF T B ACK TOTHIS POINT TOREMOVE PR ISM

INTERIOROF

TANK

EXTERIOR

FIGURE te.-Removal of prtsm from protectoscope.

t I,. II 10'11Ily by squeezing the safety grip and depressing theI II , III', nl the hydraulic traversing control handle (fig, 15) . . The

I "I' II ikt operates the caliber .30 machine gWl and the bottomII II, I, 1'1 H rutes the 37 -rnm gun. The gunner sits on the. left side

,o f I III' 1111)11111. and the loader on the right. Care must be exercisedIII ,p 11 , 111III() loader's hand is not caught in the automatic breech-IIi " I,. ," I1'(, figure 13 for ammunition stowage.

l'lljill/ll (/'il llt8.-A caliber .30 machine gun M1919A4 is mountedI. 1111 1 '1'1 '0111. The gun can be traversed 360 0 by rotating the cupola.

43


23/82

TM 9-7503-5-36 ORDNANCE MAl J'l'E'NA ICE

The gun ma.y also b tray rsed to a Jimited extent independent of thecupola. Maximum elevation is 60 0 and maximum depre sion 8%.The gun is fired manua Ily by squeezing the trigger.d. Bow guns (fig. 16).-Tl18 bow ~runs are Iocated in the Ief side

ofthe driver's .ompartment, projecting through the front plate, annconsistinz of two caliber .30 machine gUllS M1919A4 which are firedby the drivel:'. The guns are elevated manually and have no traverse.Traverse is accourplished by steering the tank. The ,

( I) J ' ush the master con trol . wi tch to the " on" position.d. (I JI(J(ilio-n.-The stabilizers should not be operated except when

I I I i ' 1 11 11 1,is in motion. A red glox from the light on the control1II'\I'~ :-;il.:rriiicshat the system is in operation.

( I) ....1 i f / ,ws .c ;a.dj'l,b,~t1l1.ent;.-After the sy -tem has warmed up turnII,, 'lill'III\~s adjusting knob lowly jn the dire ion of the arrow.\\'111'1\ 111(' gUl l begins tovibrute de reuse the ndjustment, until the\ ,11I'lIlllIg is oliminated, As 1 ' \ , check press on the breech suddenly111101 1'1+:1"(,. If the gUll. comes to rest almost immediately after aI'fllp displ: lnment it is properly adjusted. I may he. ne e SStlry

III I 111l11gl' II\(' stiffness adjustruen tram time to time as the viscosity,i I Ii II' oillIi:lnges.

I") H"'lIil (Jcl:iu8tment.-TJ1e recoil adjustment must be made byI, lid \I I!!'II Ii Ii ng the gun, Gradually turn the recoil adjusting knobIII j I", din'diOIl of the arrow until the point is reached where the gUllI, 1'1 IIlor:-;I'I ;wgillar position during recoil.

!'\ I 1'('/'/'O/,/!lal1ce.-\7Vhen the stabilizer equipment is running, the1111 1 I jII'v;lkd rn: depressed by simply turning the haudwheal. ThisI ' 11, ,11 , 1 ,"II!.':


24/82

TlY.[9-75037 ORD ANCE ]I.{AU'l 'ENANCE

and as il, sighting element. The vision device is located at the eyelevel of the gunner as he sit in position. A telescope sizh is builinto the doht side of the vision device. TIle entire vi ion device isreadily removed by pres. ing in the lever button located in front ofthe upper left portion of the headrest and then pulling on the ringfastened to the bottom of the housing. The telescope sight canthen be removed by taking off the bracket which fastens it into theperiscope. Extra visi all device and telescopes are carried in con-veniently located brackets so that rapid replacement can be mad when11 cessary.

46

:MED'IUM 'l'AI\TK M3, M3Al, AND M3A2TM 9-750

38

ORGANIZATION INSTR CTIONS:Paragrn phs

~I'I I H INI. General information on mainten al1ce___________ 38-,39II. Equipment ar d ipecial tools___________________ 40-41

ITI. Enzine and a .ccssorie 42-60IV. Fuel system__________________________________ 61-67

V, Cooling s y s t c l 1 l _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _68-69V L . Clutch .:._____ 70- 1V II. Propeller s h a f _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 82 4\' III. Transmission differential and steering brakes___ 85-90IX. Final dl'ive____________ 91-93

:\. Tracks and sLlspelisiolls_______________________ 94-99:\ I. Electrical equipment and instruments 100-118

\ II. Auxiliary generating unit , 119-121\ III. Hl.ubiJizers - 12:2-126\ JV. Turret, 127-131\ V. J'mparation for shipment and storug 132-134

SECTION I

I: 1';NlDHAL I~FORM vrrox ON MAINTEN NCEPllr(lgraJl~

"1 u --------------_ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ _ 38I I II I " II, '1 1111 .,1 1I[) t ing.,---- -- -- _ 30

'I,'l :kope.-u. The scope of maintenance find repairs by the crewIlInl ,,1111'1'uu its IIf he usinz arms is ietermined by the ease with whichII U III; i""1 (lIn b accompli. heel the amoun of time available, the. . , 1 1 1111"I'll .. 1 ( ' I ' 1 '< l in ,weather .onditions, t em p e ra tu re ,concealmentII II.', jiltl,\illiity 0hostile fire, he equipment availabl and the kill

,01 I II ' 11 I' 1' ~1 I 1111I '1 .All of the e are variable and no exact system ofI"' , I ,11111' ' :111Iw prescribed or followed,

' I 1111 ' l' I, II "w i ll ga r c the main tenance duties which may bepedo rmedII \ 1 1'1 ' II IIIIJ : I "1 11If] ~1llte 1111nee personnel. All other replacem en ts andI' I' I II 11III III'I){'rI'OL'ITIed by the ordnance maintenance personnel.

( I) 1'/lllilll' /tHl!)-E(]93,11:11~'IIIP,~1'I'vice and remove ( see par. 59).1 \ 1111111 ' ,.l.L \'XlI:IIlSl, and muffler replace.I'"d, \:11 \I' push replace,

47


25/82

TM 9-75038 ORD AN E MAl TTENANCE

(2 )

Val ves, clearance a ljust.Valves check timing.Valve rocker, replace.Oiling 8ystern.Cooler, replace.Cooler bypass valve, clean check, and replace.Tank, replace.Lines xtemal, lean and replace.St raine rs, clean .Dilution val ve, clean and replace.Cuno filter, disassemble and clean.Cuno filter, r pla ".Oil pressure adjust..Pump, replace.Temperature gnge, replace.Pressure ga,Q:ereplace.OooUng system,.Fall cowling, tighten and clean.Fuel S'ystem.Pressure l'cgn lating valve, check and replace.Fuel .ut-ofl ' valve, check and tigl Itell.\ ll'bure tol', l ' place.Carburet r bowl, drain.arburernr elbow replace.

A it ' cleaner, ieplnce and service.Gaskets. carhureror, to elbow to ruunif'old, replace.Lines, clean, repair, aud replace.Primer lines, replace.Prime)' pump, replace.Pump teplace.Filtel' rep lae and service.Tanks dean and r place.Eleot1'ical sy. stem.Magnetos, -eplace ,Magnetos, time to engine t.imi11g when illstnlling magnetos.Magneto points , adjust.Ammeter replace.Voltmeter) replace ..Switch, magneto replace.Switch battery re lace.Switch, starter, magnetic , replace.

Fuel cut-o ff. soleno id replace.

(3)

(4 )

(5)

4

TM 9-75038

(1\ )

ME'DWM TANK' M3 M3Al, AND M3A2

S( arter assembly replace., 'tarte r solenoid , replace.(lcnerator assembly replace,(hnerat.or ch eck ou t pu t.Voltage regulato r, replace.r~o()stel' coi 1, replace.Ba ttery charge replace 01' service.Si rcn, replace.Fuse block assembly, replace.( :0lIe .tor ring assembly service and rep lace.Auxiliary generator unit, servi e and replace.A uxiliury generator, replace park plug.\Vi ring rep lace .. J 'I':]('C trou bl e wi th light,Hpnl'lc plugs replace.I ~III ' ness,. ign i ion w i 1'e a ss em b 1y replace...,'I/ ,~ jlC1I8tOn.

1~(lgje and idler wheels replace.Holll~l', track supporting assembly, replace.l Iogip omponents, replace.TI':"'I,;, replace 01' reverse."'!':ll'k, components. replace.WIIl'I,1 bearings and oil seals, bogie or idler, replace,'l'I'llI'k. adjust.\'"III(I~ springs, replace.(il'Ols('l's,install and remove.

I 111 /1(lild turret,

I I

'l'11-!ld".ll 01' replace holts, nuts, and screws., '- 'PI li H, replace.l usulu l JOIl replac 01' reverse.\ II 1 ' 1111 ; - ; ,replace.1111'1'1'111 gun plate , rep lace .\ ' I Hio 11 device, replace.

"I 'II Ii pod, doors and peephole 'overs, service and replace.M IIllgll:II'(ls, repair or r place,1'1'(//I,wrissil!'tJ. mul driving 1I,nits.("111111, ndjust find service.( ""11, 11 Jl1 :1 (,('S 01' bearings, replace."i 11111 Ilrive assembly. replace.I i"III' 11':li11 nssernhly replace. (See not.)IIIII,~ 01 "I"'(wkd"s repla .

1"'III",II,'j' : . ;11111 ' ("servie , replac .

'J 49


26/82

TM 9-75038-39 ORDNANCE MAINTENANCE

Shift lever' replace,Steel'inO' band replace, (On latest models 2d echelon can 1'6-placebthe br~lm bands, On he older m.odel ' it. w~llb .nee.s-sary to take apart the brake drum and differential housings morder to remov the brake bands. In this case ordnance per-sonnel will perform the job.)

Steering brakes, adjust.Steering lever repla ceoTransmission replace, (See note.)

(9 ) Misoellaneous.

Painting.Cleaning.Homelite unit service and replace.Ln brication.Hydra,ulic steermz mechanism refill oil reservoir.Armament) service.Tachometer and cable, replace.Speedometer and cable) 1" place.

NO'rl':.-Th. using M'lD is nnthouleed to remove and reinstall engl ne and powertrain assemhlies, which includes ttl transmtssto and diffenmtLal 110usings.How '1'61', tl) replacement of an engine with another engine or U1e l:epJacementof a power tnlin !IsSem111ywith another Dowel' tratu assamulv must not be doneby the nslna aX'1I1S unless autnnrtzatton is receiv (1 f rom ordnance maintenance

personn I.

39. Engine trouble shooting.-Before starting any engine alwaysclear the cylinders of hydrosta ic lock by turnintr h~ engine .over wo

complete engine revolutions by hand. If extra l"eSlstHn~e IS felt orthe engine cannot be turned over, rernov the spark plugs JU.~e lowerthree cylinders to drain the rat ped fluid. If after draining theengine cann t be turned over, call ordnance p r onnel. If, ~n the ?t.hel'hand, the engi11ecan be trr rned over by hand and the engine fails tostar t 'af ter repeated attempts, anyone or combimLtion of the followingconditions may be the cause,

a. Engine fa.ils to turn 01!e'/" l .uhen starter solenoid is 7J1"essed.-(1)

First check the ba tery gl'Dvity, ,(a ) If reading is 1.150 01' less replace witb fully charged batteries

and have the discharzed batteries recharged.(0) If reading is :pproximi\,tely 1.280 the battery IS fully charged.(2) "ext check the condition of battery cable .(a ) Examine battery terminals for corrosion und. b att ry cabl for

shorted or broken sections. Clean corroded terminals "and replace

broken cables.

50

MEDIUM TANKS M3, M3Al, AND M3A2

TM 9-75039

I I,) Examine for loose connections and tiznteu clamps.I") O v er a te the starter switch to ascertain if it is functi al l i 1;,

"11 \" on e m an l isten at solenoid for click as button is depressed. If no 11t '!-i~ 1ieard, replace the olenoid 01' di sconnect the battery-starter111,,101' r-uble at the star er motor, and while another person operatesrh" ~ r:lI'lpr switch, hold the cable against the housing, A spark should"""111", 1 1 'it doesn't, replace the solenoid,

( I) If the tarter does not operate after s lenoid clicks starter1,,,"ld hI' replaced,l, I(n,lline mllrns bu does not sta1>t.-(1) Check the iznitioa

\ 1"111,

I II) ( 'heck the ]O"nit:iOllwires for breaks worn sections, and Ioose'"1Illl,,'liollS. Remove a wire from the spark plug and heck for1'111'11101' spark,

II,) I r the length of spark exceeds 3A ,inch, it is an indication thatIII 11"'lsl('1" coil and magnetos are functioning properly.(,) Next remove an upper and lower cylinder spark plug and

1 1111Ii 110 1'01" broken porcelain and corroded bum t or dirty elec-I I'" 1,.:. l l dir y, clean and adjust all the spark plugs, Replace allIII ,;I I'll 01' burnt spark plugs.

I d I II' t he spark js not of sufficient length, then check the booster]I II 1111, I III agneto.

I, Inspect the booster coil by Ii tening for a buzzing soundwhile the operator presses the starter switch. If abuzz is not heard, replace the coil.

) ('heck the output of the booster coil by disconnecting the

hizh tension line to the right magneto at the magnetoand turn the engine over by starter motor. The sparkwhicl occur hould be approximately 3 fsin h long.H the spark i. horter than % in 'h replace th coil.Do not attempt to adjust the park,

I, (IH(I; the magneto contact points (gap 0.012. inch}, In-spect the points for pitting or buming. II the pointsure pitted or burnt, it may be due to a loose or defectivecondenser 01' cverlubrication of the magneto. If thepoints are pitted slightly, the points may be smoothed\\1 i .I, H. -fine file or abrasi ve stick. (Adj ust " ap.) If thepi 1i Ills are badly pitted or burnt replace the magneto.1)(/ not attempt to repla e the points. If maznetc does1 11 ,1 . 1 '1 11 1 tion after pre eding check) replace magneto.

I'I I I""'k (Iu- I'Hel system,( I I '1 1 1 '1 ,1 ,( 11< "amount of f ue l in the fuel tanks.

51


27/82

TM 9-75039-40 ORDNANCE MAlN'l'ENANCE

(b ) Check to determine if the fuel valves are open.(c ) Examine the carburetor for flooding. (Carburetor will be

wet and Ieakin 0" . ) FIoodins is usually due to sticking of the floator leakage of the float valve. If such is the case replace the

carburetor.(d ) Cheek the fuel flow.

1. Disconnect the inlet line at the carburetor turn the engineover by u ing the -tarting motor, and watch for fluid

flow.:8. If no thbid flows di 'connect the carburetor inlet line at the

fuel pump and blow through the line to determine if itis plugged. If it is plugged clean by blowing com-pressed air through the Iine,

3. If t.be inlet line is open, the trouble may be i11 the fuelpump. Te t as follows: DisCOlIDect the inlet fuel Iine tothe fuel pump at the pump and if the line is open fluidshould flow. If fluid dues not flow the lines arepugged. Clean the IU e l lines. If fuel doe flow. re-connect the line to the pump. Now turn the engine overby starter rnotor: if no fluid appears a.t the dischargeside of th pump: repla e it.: if fuel flows, h ak thepressure of fuel being delivered by the pump (3pounds) .

(3) After performing rill the checks enumera ted if the enginewin not sta rt, substi ute a ]1'W carbu 'etm' and attern] t R start. Ifthe engine will. Dot start then remount the o'f"igv/'wl en .bur to!" and

call the ordnance personnel.

EQ< IPMENT AND PEOIAL TOOLS1'arn graph

GelleraL ------------ 40Fire extinguish i 1g systeru ----- 41

40. General.-The items listed below are carried with the vehicleand are strapped in place on th exterior of the hull or located inside

the vehicle in the most conveni n places available.

List of Cl}"lJ.'ipm(lnt Where c("rried

Ax chopping, sing1 hit, 5 lb On tank.Bel t. sa fe y - In tank,

Book Ordnance MotOl' (0. O. Form No. In tank.7255) .

Cable, ov,>mg --- ----- On tank.

52

MEDiUM TAi:>nr M3 M3A 1, AND M3A2TM9-750

40-41

Li.~1 o t cq'l('ipl!l(mt( , I 1 1 ' J lVlrel"1l ( ){W1"iml, I' \ " ~' . 1('1]( Ig1t (sun glare) On tank.

I II 111"11:-< (2) _ -I' I . I --- ---- --- --- -- Lin tank: 1 in turret.1,\ III;":IIIS Il'!'S, lire, carbon dioxide 4-1b f i J Id 1. .("). ' ., -e in tank' IlJ1 turict,

1';,llllgllisher fire, carbon dioxide lO-lIJ fi'll-d I t II" , . , 1 e n arur under turret.( OJI' IIlI"dlUl11 tank NI3).

I :I1I'~I,.s, uutomobilj, amber, pall' (QMC In tauk,I ,slid.

( IIIIIS(I'S (for medium tank M3) In tank11 " ) 111 ( " : tank-:- ---- -- In tank:I 'IIIIP, 1.lIspcdlOn M. T. 1113 with bulb In tank.1,1'\" 1 " ,l'ront door (for medium tank M3) In tank\ 111111 ) 1 " 1 "picl~ Ml (&-lb. head) On tank.I : 11111~lI'k.1% lll., keyed individually, 2 key On tankI Illillli. 12 b y 12 ft In tn.nk.)1!r11'I, D-ha.ncUn round point On tank.

11 "11p. leather, type D (1% in.) 13 in, long On tank.(III'" each for ax, mattock handle mattock11I'lId, and wrench).I ,u p, le:tther, type D (1* in.) 25 in. long On tank.I rill" tripod).

,\ III"slt~eld (for medium tank M3) In tank,\ (1 11 1)kit (No.3) is included with each tank.

I I. ~ir~ exttngutshtng system.-a. Operation.-(l) The fireI \111I~!IIShllll;! sy item IS entirely manual in operation. It i s there-I"II' imperative that there be as l it tle delay as possible in d' . I ._III' II ' . .ts if . . ' ISC lar g~ . u ~as, as 1 s. e .ect lveness IS material ly increased by catchin

llin 111 "1 ' III the begml1lIlO'.g

('I) To operate the ystem, pull one control handle t 'I hII 1 " ' . onlO an-I 1",:1 rc. ocated inside th tank at the turret basket bra 'ket adjacentIII 1111'.uol g~ges and outside tank above the motor com~artJl1ent.II II,. '~('('ond fire praor to recharging of first cylin [er pull other1111111"111handle. '

l\o'I:,-TuC' gas can also be released at cylinder by removing pull-o t < :",,11',,1 head and rotating manua l Tevar, u pill 111

I,. 1.)(~:~~7'iptio:t.~ (1) The fi re ext inguishing system consist s of a sup-IIiI "I \.,1 J bon dioxide gas stored 111 two steel cylinders each h ..

.'1 fl' . . " . aVlng aI II) uu I .y 0 0 pou~lds of carbon dioxide: manual release aear forIlldl'jll'lIdent ~pel"atlOn of each cylinder; and tubinsr to co:;vey the'II III Ihe engine COl~pal't.ment. The tubing is terminated in shielded

d I I~ 1 1 1rge nozzles which effec tively dist .ribute the gas.

53


28/82

TM 9-75041 ORDNANCE MAINTE Al'-,TCE

(2) The two gas cylinders are conn cted to the supply tubing bymeans of a doubl -check tee, which tee pr vents the 10 s of gas intothe crew compartment should one cylinder be operated while theother cylinder is removed for weighing or recharging.

(3) In addition to the built-in sy tem for the engine compart-ment described above, two 4-pound portable extinguishers are pro-vided for small fires in or about the tame Full operating instruc-tions are found on atinzuisher name plate.

0, Pri'nciple,-(l) The fire extinguishing sys tem uses carbon diox-ide as the extinguishing agent, Carbon dioxide (not to be confusedwith carbon monoxid ) is n t poisonous but L


29/82

TM 9-75041 ORDNANCF~ MArWrENANGE

ing a pin or nail in cont.rol. head shaft and turning. count~rclo?kwise(looking at J11aJJual lever SIde of control l~end) nntil c~utch pm. andarrow art> l ined up as shown 1Il fig 21. If systern has been operatedat evlinder replace pu 1I-(JIlt .pi nand s.en,}wu:e.

oJ I h 1 J a I to n UL 1\ :( >(:f>l'tain(4) J 11spect the orifices ill th e s ie (le. llOZZ es 'thcy are clenr o r al l forei gIl matter.

T O O PER AT E SYSTEM ATC YLIND ER RO TAT E LEVER

PIN A ND A RROW MU STLINE C JpWHEN CONTROLH EA D IS IN SET PO SIT IO N

CONTHOl HEAD

RA PO 5692-FJ(~ un Ii:: 21 .~F ir e. axt ln gu i : s i le . l : ' ~y~tCl!1 co Ii t:L'ol head.

(5) Reinstall the fully charged cylil\der as fo110\Y8: .(a ) Set cylinder in place and tighten e1amps~anc1t.-lgh~ t~ a~_o\:

1'01. any turning. 0+ cylinder that may be required III coml.ectm b

tubing. _ . . 1 ck t . d . lv(b ) Replace connecting tube between double-Cle . tee an va e

outlet.(c ) 'I'izh ten cyEn del" clamp securely. ." . .. '(d ) M ~'cecertain. control head i,s i n set. positiOl: (pm hned up with

arrow as shown in fig. 21) before remstallatlOn. Insert control

56

MED~ 'l.'A:i\'K& M3 M3Al, AND M3A2TM 9-750

41

Il


30/82

TN: 9-75042 ORDN Al'fCE :M:AIN'fENANCE

SECTION III

E GINE AND A ESSORIESParagrupb

42eneJ'al descrtptron - ---------------------- 43Construction and mstallutton __ ~ _

44ha ractel'istics_ ------------------- --------------------------------- 45Accessory case and drive mecbanism ~ _

46il pllmps ~ -------- 41Mr,nttolds - 4S

Ignition shtelrllng barness__________________________________________ 49

Magnetos ------------ - --------- ----- -------------------- --- ------ 50Spark plugs ------ 51

Booster coil., ---------------------------- 52Start l ------- 53Gen rator _

54'uel pomp ------ 55

arbur tor , ---------------------------------------------------- 56Ai l' clean ers ---- --------- ---- ----- ----- 57G orernOl" - - _

Engine Iubrlcntlon and Illbl'icauts___________________________________ 58Replucemen of englne_____________________________________________ 59Valve adjl1stments________________________ 60

42. General description (fig. 22) .-a. The Wright Whi.rhvindR-975-EC2 it single row, air-cool c1 ,radial, aviation type engine isused.

(1) Dir'ection of rotation (from real' 01' rnazn to end).C r an k s hn fL _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _lockwiseTach meter clnve____________________ 'ountel 'c lockwise

Fuel p ump _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _Do.Starter . Do.

Do.enera tor -- - -- - - - - __.

(2)

M:agneto _

C'irouit gaps.Masrneto breaker points gap 0.012 inchSpark plug gap mica plngs 0.012 inchEngine oil. _ .,Pressur should. be within foll wing limits:

Minimum 50 lb.

Qlta.~~~iI~~:~~~~~~~~~~~~~_-~_-~~~~~~~~~~~~__:_~~~~~~:_-~~ ~~~.Temperature at inlet : . .

Maximum allowable, degrees Fahrenheit 190Desired, degrees Fuhrenheit., 140

Do.

(3)

58

MEDroM TANKS: M3, M3Al, AND M3A2TM 9-750

42-43

t, '1'111' ! \\'0 magnetos, starter, generator, an i fuel pump areIlill'lIlkd 1111 I Ill' rear face of the rear crankcase section (fill'. 22). Tbe111,1,1",'1111' is mounted on the extreme lower end of the real' section,

I,I t Ii is sl'ct.i.on the flywheel end of the engine will be r ferred toII II \I' .. r1'1111[1' of the engi 11 and the other end will be referred to

IIII' """;)1'" of the engine. The terms "right and "left" are usedIII1II !'I,rl'I'('IIl'n to th eng-in as viewed from the real', H rizontal111111 \'PI'iil'it! positions of the engine will be reicned to with respect

I. IIIl JI"~ jj 1011 cd the crankshaft. Direc ion of rotation i. etermined1,\ \ 11'11ill;!; ll'om the rear of engine, 01' in the case of side drivesIII 1"IIllillg toward the crankshaft.

1.1 Construction and installation.-a. Oonstruetion.-The nine, \ 1111Ii,'I'S 01' til e engine are ra d:ial1y moun ted on the crankcase UJJd10 (111111 ,1 ~ l tl ll l 'd . A formed shielded conduit or harness contains all.111 II II 1I1g' fill' the enzine including the high-tension cables. Baffles'" III lilliI'd over and be ween the finned cylinder for cooling.

1 /" ,/ ,,1 1( //ili1l.-The engine is mounted in the tank as shown ill111 ' ' ' 11 'i'(

5 9


31/82

TM 9-75044---46 ORDNA r E Mi TENANCE

44. Characteristics.Wrigh t, rad ial, air-cooled.R-975-E 2.

Make and type _

Model aJ1d series----------------------Over-all diametel"-- -- - - - - - -- ---- - - - ---Weight inc luding a 'ce.sorie ---- -------Iorsepowel' ------ ------ ---------- ---umber of ylinders------------------

Clearanoo between valve stem and rocker .roller cold-- 0.010 inch.

Eirinz order (clockwise v' awed at mag-net~ e n d ) - - - - - - - - - - - - - - - - - - - - - - - - - - ]-3-5-7-9-2-4-6-8.

Location of No.1 cylinder------------- Top.

45. Accessory case and drive mechanism.-The acce ssory ~~s~. s ttached to the rear face of the crankcase and houses the gearlS L . . h th retos startertrain that chives the various acce series, sue as e magI,) 1O"ene ratO I" e tc. . . .. 1-" 46. Oil pumps (fig, 22) .-a. The supply of ~l] 1ll the engm~, 1 an~-case is maintained by oil pumps which draw o~l from the e~1g:ne 0 :1tanks Iocated at the bulkhea 1 between the eugme a~d ~ghtll1" COTIl-pa,rtments 01' whih chculate the oil within the engme Itself, Th~seare gear ~ype pump' whi 11 are support.ed on the, lower le~ Sl~~of the rear crankcase ection ill the case of the roam puml~ and,.the no e section in the cas of the other sca,venge pump. 1h mumpump is divided into two ections : a separate pres~lU'e ,pelrop and ac,,'LVeIlO"eump. This scavenge pump return the 0 1 1from the Upp~l'~ectionb of th sump to the oil filter. Tl1e scavenge pump located 11 1the nose s etion removes oil from the low~r I .tion of the.' n~np.Both return lines from the scavenge P,UlllPS ]0:]1 tosrether befOl.e~lLI~-nina into the Cuno filt 1". The main oil pump incorporat 8 (, pressuiX'eli~f valve which comprises a ~llr il1g-1oac1ec1hull ,thnt r ises ~vhen.thedesired pressure is reachecl and allows he exc ~- Ol~ to be dl'Ul:led intothe inlet side of the pump. Pressure regulunou 18 accomphshed byturning the adju ting screw '10 kwis ,to nl1~ the pressur and CO~lll-terclockwise to lower the pressure which raises or lowers the tension'h ' ( c: 22) The oil pres ure should be between 501ll t e spring see llg,. ' .and 80 pounds per square inch :in nOl'~a] operatIOn. ,

b. Replacernent.-To replace the 0 1 1lump assembly-t d utlet line at Y(1) Disconnect the inlet line at connec 01' an 0,

connection. .(2) Disconnect governor linkage at carbu1'etor connectIOn.

(3) Remove oil drain at governor.

45 inches.1,370 lb.400.9.

60

TM 9-750MI'JoDTrrM TANKe M3 ;M:3Al, AND M3A2 46-48

( I, 1"'JlIOVC the safety wire, itud nut, and plain washer fromIII" l'II,lil sl uds OJl the main pump casting and remove the pumpIIPIII 111l' section o r the crankca 'e. Caution must be exercised to11 '1 ') 1 i 'I II '1 ' i l !l Isnhstances out of the crankca .. se during the operation, 1 '1"11'1111 ' ni l purnp and zovernor.

Ill) Tn insl al l a new pump, proceed in the reverse order, being1 1 1 1, ,1 '1 1 1 I ( )Ii l l l ' up the drive geaJ' properly.

, '1 '" "1 ( ' : 1 . 11the sti-a i ner in thf' oil pump, remove the temperaturel'lill, 1 1.1 'n-moving the n ut h olc li nO ' the bulb in the re ess. R move1 11 .1 ,'1 "1 11 1strainer covel', . pring, and strainer. In replacing the11111111')' ljt~

sure that the ga. ket is ill zood condition and centeredI" "II'I'I.\' ill i ts recess.1'1. Mnnifolds.-a. Ituak e.-The intake pipes are fastened to the

1111111 . , 'PIIl't. connection of each cylinder by means of a flanze and11 , 1 " " ,'n II screws, The inner end of each il l ak p.ipe fits into the0 1dill 1')' ",[,l,tion o r the crankcase and is sealed in place by a rubberI Ii II,I! pack ing uni t./' 1\,jl/llI'I"~t.-The exhaust manifold is composed of wo sections,

'1111' 1 '1I'llit' l'ight side and oue for the 'left. ide of tho engine. The111'1i1:; hrunch pipes are mounte rigidly at the exhaust port flanges

III 11,1' (',\'lindeI'. The two outlets pass through the rear hull platesIII Ihl' III Iliners,

I ,.... II/}(')c/uwgc1,.-The upercharger is used to force fuel mixtureI l l Io l "1 pl'l~SSllre into tbe intake ports of the cylinder..t ,l/lIlIi/Old and mufller' 1 ',.'l17wval.-Certaill sections of the mani-

I.. l.h IlIlIy be removed with the enzine r maininz in the tank, TheI 1IIIJd"I!' manifold cannot be removed with the cnzinc in the tank,II" r ,,11"willO'procedure is 11 ed La remove the entire muffler a sembly :I I \ Rpmove rear top plate,I ill R(,lliove muffler: and elbows by removing 4 bolts on each

1111I11111i1l.!.!;lbow, The muffler ca n be disconnected from the engineI 1 11 11 1,,1.uauifold by unclamping the manifold .onnection and pI h-III~' !III' pipe on the manifold side up into the muffler in order to, 1 '111 II,, 1,'1'0 ends (see fig. 22).

Hi. Ignition shielding harness.-All parts of the ignition wir-III v hlll are shields I to prevent radio int rference, The shielding" " I ~ rructed so that if any part is damaged it may be readily

1 '10111"( ' "without discarding th entir shielding structure. The ends"I II . . 11111 tlui ts are eq 11 pped with an el bow w hich attaches directlyIII til l' ... hivlded spark pl110 and facilitates ea y removal, The igni-l!rd IIIII'III'~S should be inspected at regular intervals to see that all

II" 1"1111 : - :ure tight and that the conduits are nO L crushed or broken.

61


32/82

TlVI 9-75048

62

TM 9-750MED'RJM 'l'ANKS MS, M3Al, AND :M.3A2 49

119. Magnetos.-a. Description.-Dual ignition is furnished by111 '0 Il ln .g n t os mounted on the accessory case. The right magnetoIiI'PS the front spark plugs and the left magneto fires the rear plugs.' 1 ' 1111magnetos are equipped with au omatic spark advance, are!lidded to prevent radio interference, and are flange mounted.I ) , ,Jil,iU8tment (fig, 23).-Remove the br aker cover by releasing

j h, \ sa Fet.yl'il1O' on each side. Usinz a, feeler gage, measure the clear-1111


33/82

TM 9-75049-50 ORDNA~ CE MA1N'l'ENANGE

(3) Remove the two clistributinO" blocks and rotate the ~ng~newith the hand crank until the. wo marks on the rotor gear coincidewith the two marks on the magneto housing.

(4) Remove seal wi re from the three nuts which hold magneto in

place.

R A PO 4234

(5) Remove the three nuts holding mrurneto to accessory case.

NOTE.-Care mnst be tuk n that the cruuksluif t is nut tUl"IleUuntil the new

magneto is installed.

(6) Remove masmeto. .(7) In replacing the magneto put a few clro~s of ellgll1e oil on

the masneto eoupling and turn th magnet-o until the two marks onrotor o~ar coincide with two marks on the magneto housing. Themagneto may be lined up by tapping to each side. Continue with the

reverse of the above steps. .50. Spark plug 'S (fig. 25) .-a. The spark plugs used all this e~-

O"jne re the re{rular aircraft type, BG-314GS modif ied, and are radio... I:>

shiell1ed.

64

TM 9-75050

(J H"p/lIf(J/I.("nt wft(l renw'llat.-(l) t the time of the 50-haul", 111 ' , 1 ( ,III" whenever spark plug replacement is I O l U 1 dne e sary, the1111 1 '1 ' l ' i " i 'n IJ I Iplugs will be replaced by serviceable plugs.

(')) 1'1) l'i'IIW/Je the spade plugs !1'o,/n the en.qine.-(a) Remove the110111 IInd n'n!" top plate OY(>rthe engine.

RA PO 2756

I Ii 1 Remove the cable ennnection with 11 %-inch open-end wrench.r'PlllOve the spark plug from he cylinder recess with a spark plug1II"('Ilch (I-inch wren 'h No. 140).

(/") Remove inspection plate from bottom of hull unde r engine1'1 11'1purtm ent.

(Ii) To facilitate removal of front spark I lugs , remove inspection, "1'1l" plates on Ian cowling.

((.) The USe of a socket wrench with 11. unive rsal jo int extensionflwilitates removal o f certain plugs the location of which makesrr-uruva] difficult with all ordinary oclret wrench,

I f) Five. plugs Illay be removed from the front and five fromII,, rear of the engine by ma.dling down froru the top of: the COTJ-

~!H606-"'2--5 65


34/82

TM 9-75050 -51 ORDNAN E MAl "'rENA (;E

partment, 'The remaining plugs can be reached through the openingin the hull beneath the engine.

(3) Wilen installing spark plug in t]le engiTle do not use wrencheswith handle more than 10 inches long. It is possible to distort.certain sections of the plug if too much force is u eel in tightenillgthe plugs in the enzine cylinders, olid copper O'Hskets are to beused. When spark plugs are raplaced tlw threads should be cOI!tedwith anti:-;t\izp C()111POllllcl to ptevent "frpE'zillg' of the pll lg~.

FJOURE 26. l~lectdc starter.

51. Booster coil.-a. DeSC1'i7Jtion.-A booster coil is provid dwhich upplias all intense aux ili ary spa ,rk :)Cl'OSS the points of thespark plugs to facilitate engine, rarting, The booster oil switch is10 ated Oll lbe iustr-ument panel, and is used to connect the booster

coi l at s tart ing.I!. Replacem,ent.-A the time or the lOO-honr check, or whenever

boosterco il replacement is found necessary, the unserviceable unitwill be replaced by a. s erviceable one. Disconnect. cables with shielded.onnection to booster coil remove bolts holding oil to bracket, andreplace with new coil. Disassembly, servicing, and adjuctrnent ofth'e coil will be done only by ordnance rnnintenance personnel.

GO

MEDIUM 'l'ANXS 3, M3Al, AND ~3A2TM 9-750

52 -53

52. Starter (fig. 26).-a. Description.-A 24-vo lt di rect electi-i,III rtcr is used on this engine. The starter should be used only forf'l"illil,ing the engine. n, must uot b 1I. ed tu move the tank when the1'11g:i1lC is not fun itioning.

I). Hand (.,')'('l117cing.-Pl'ovjsion is made at the top of the tarter1111 i t for hand cranking.

r, Electrio (franking.-A starter switch is located on the instru-1III'Ill. panel.

rl . Stal'te1'.-If the starter fails to operate proper! it should bep'pplflced with 11 ierviceabla starter. The followm:o- procedure gives!lIP method for removal and replacement of the starter.

( 1) 1


35/82

TM 9-75053-55 ORDNANCE MAINTENANCE

c. Repla.celluyn,t.-A :faulty generator shou ld be replaced as f 'ollows :(1) Remove the terminal guard and disconnect leads.(2.) A11 leads should be marked to identify their proper position

for replacement,(3) Remove the four nuts holding the generator to the acces 01'Y

case,(4 ) Loosen the generator retaining bracket nut and slide the gen

erator to the rear.d. Oilleakage.-If excessive oil is present in th generator at the

time of inspection the generator. hould be replaced.54. Fuel pump (fig. 22). -u. Description.- The fuel pWD p is

mounted on the engine accessory case to the right of the generator.b. Maintenanee.-At the 50-hour inspection, check for leakage at

the joints and fittings.c. To remove and replace fuel pttmp.-In the event the fuel pump

fa.ils to snpply a sufficient quantity of fuel, the pump sno 1 11be re-place 1with a. serviceable unit,d. Th following procedure will he observed 01' removal and re-

placement of the fu I ump:(1) lose fuel shut-off valves. The two main valves are located

in bulkhead below oil tank.(2) Remove cap screws and open rear doors to engine compartment.(3) Disconnect fuel lines attached to pump.(4) Remove locking wires and nuts holding the pump to the ac-

cessory ca e.(5) Remove pump.(6) To replace pump reverse tbe procedure.55. Carburetor (fig. 22) .-0. Description.-The carburetor is at-

tached directly to the intake manifold in the bottom of the enginecrankcase.

b. Maintenance.-Once the carburetor is properly installed verylittle attention is needed between major engine overhauls, A fuelstrainer is located at . he rear center of the carburetor and may bereached by the removal of the large square-headed plug at the bottomof the carburetor. A small squareheaded plug is provided as a drainin t.he bottom of each float chamber. The strainer and drain plugsshould be removed frequently to remove the accumulated dirt. Thefuel supply should be hut off before removing the plugs. T~le entirecarburetor should be inspected to see that all parts are tight andproperly safety-wired.

c. Replacement.-Should it. become necessary to remove or replace

t,he carburetor the following procedure should be followed:

68

MED'lUM '1' KS M3 M3Al, AND M3A2

TM 9-75055 -56

(r ) Check to see that fuel shut-off valves are closed.(~) Disconnect the fuel line and drain lines,(:3) Disconnect the fuel cut-off and accelerator linkage.(l) Disconnect air intake connections at flexible connector.( I }) Remove the locking wire and the f ur bolts hold i ng the car-

hlll(tO' to the intake manifold base and remove carburetor. Dis-!'OIII1Cctil' intake pipes.

(Ii) To replace carburetor reverse the procedure outlined above.d. Ar1justment.-A her a new carburetor is installed it should

hI' udjusted to the engine, Two adju: tments are I rovided, one forIdling speed and the other for mixtur qua.lity, The throttle ad-justment on the carburetor (see fig. 22) is set so that the enzinei d l os between 300 and 40 0 rpm as read on the tachometer. TheIII ixture control lever is moved to the righ (lean) until he engine))('gins to run unevenly. The 1 vel' is then moved one notch at a timeIII the left (rich) until the engine operate evenly. .56. Air cleaners (fig. 36) .-0,. Desciiption.-Two air cleaners of

Ihe oil bath type are provided, one at the right and one at the leftn~lr ngine compartment.

b. 1 J Iaintenttnce.-After each 50 hours of normal engine operationHI' daily in extremely dusty operation, ervice the cleaner in thefollowing manner (see fig. 36) :

(1) Remove the six wing nuts from bottom P ate of cleaner, andIIIke off bottom plate.

(2) Remove cup and flute assembly by liftine up slightly andIwisting in a counterclockwise rotation. Take flute assembly out,or cup.

(3) Empty dirt nrid oil :from cup, and clean thoroughly, Refilll'lif' to proper level with oil specified in figure 12. Care should be(uken not to fill cups over the oil lev 1 mark.

(4) vVhen replacing the cups, make sur tha,t the cup assembly isproperly latched.

(5 ) Place the bottom plate Oll the cleaner and fasten with thumb-'IIWS.

r, ReJ~lacem,&nt.-.n the event it becomes necessary to remove or1'l'l'iac' the air cleaners, proceed as follows:

(!) Remove 1'e[


36/82

TM 9-75056-59 ORDNA, CE MAINTENANCE

d. Olean.filter.-Wasb filter element with cleaning fluid or gaso-line dry, and blowout with compre .ed air in reverse direction tonormal air travel.

57. Governor (fig, 22),-1 'he zovernor is used to regulate andlimit the speed of the engine after the enzine has been manuallynccelerated. This prevents dangerous overspeeding. The unit islocated OJ) the accessory case below and slightly to the left of thegenerator. The governor i sealed and should not be tamperedwith.

lrlGUHH 28.-11101] JJ lin g Or engine.

58. Engine lubrica tion and lubricants. -a . pecification8.-Refer to section IV, chapter 1.

b. En,qine system (fig, In.-Oil is drawn from the oil tank anddelivered under pressure by the oil pump through a filter to all thenece. s ary bearings and other I arts of the en zine through drilledpassages. The engine scavenge pump returns the oil to the oil cooler.The preSSllre relief valve on the pump is adjusted to prevent theoil pressure from ex ee ~jng 0 pounds.59. Replacement of engine.~a, Facilit ies must include the nec-

essary engine stand and hoisting fncil .i tiss.b. To re1TW'e engine (see fizs, 9 and 30).-{1) Open master

switches beneath turret . .

70

MEDLUM '.1'ANl


37/82

TM 9-75059 ORDNAJ."\f E MAINTENANCE

(14) Disconnect clip holding temperature (TaU cable at generator(%- inch) . Replace screw.(15) Disconnect tachometer drive cable by unscrewing knurled nut.(16) Remove conduit and wires at generator. (Pliers, screw

driver, and ~ -inch open end wrench.)

F'H::UU...: 3-0 .-Ho .i st ing o f ~_ngine , side vlew.

(17) Remove conduit and wire from starter at starter. (Pliers,offset screw driver and o/i6-inch wrench) ..

(18) Remove magneto grouncl wires and booster wire at junctionbox.

(19) Remove upper shroud section (%Il-inch wrenches).(20) Remove inspection plate una r hull (%-tl'h "Tench and

hydraulic 600I' jack).

72

TM 9-750MED'IUM TANKS M3, M3Al, AND M3A2 59-60

(21) Di connect. conduit and wire at cut-off solenoid and removeclips from banjo.

(22) Remove accelerator rod clevis PUl beneath engine,(23) Move slip sleeves on exhaust pipes away from joints (%ij-inch

....enches).(24) Remove engine steady rest bolts (lY4-inch socket and exten-

sian' !lIs-inch open end wrench).(25) Disconnect ground strap from banjo (%6-inch wrenches).(26) Disconnect primer line at rinht of cut-off solenoid (% 1\-

and %-inch wrenches).(27) Disconnect oil PI' sure line at right of cut-off olenoid

(i}1- and %-inch wrenches).(28) Remove sta .ter solenoid and bracket from brace (%6-inch

wrenches).(29) Di connect breather line (crankcase to expansion tank) at

forward end of metal tube located over top of engine. CHose clampconnection. )

(30) Disconnect 2 muffler pipe support brackets from banjo(,56-inch wrench).

(31) Remove tire extinguisher bracket tube and horn a. sembly frombulkhead (%6-inchj L-inch; 11,1.-inch).

(32) Remove bolts from companion flange (~I 6-inch wrenches).(33) Instal] ] i ting sling on enzine,(34) Remove banjo bolts (pliers, two i%6-inch wrenche ).(35) Lift engine from compartment with A-Itarne. Set in stand,

Insert banjo bolts and C-clamps if necessary.

NOTu:.-Keep all nuts, bolts , screwaatc., in tool box until ready for Installn tionagain.

c. To install enqine.-Revel'se the above procedure.60. Valve adjustments (flo. 31).-Valve timing check an i clear-

ance adjustment (with enaine cold) :

a. Remove rocker box covers and ga kets from all y lin ers.b. Remove rear spark plugs.a . Remove two acljacen % -inch hex elastic stop nuts ....hich hold

the flywheel and fan together) and attach the timing scale portion ofthe timer using the nuts ju t removed. Insert tha top dead center in-dicator in the spark plug bole 01 the number one cylinder and deter-mine the top dead center as follows:(1) Turn the crankshaft in the normal direction of rota tion (coun-

terclockwise when lookino at the flywheel or forward end of theengine) until the pointer of the top c~nter ind.icator register Z 1'0.

73


38/82

TM 9-75060 ORDN~~CE NUUNTE ANCE

(2) Iamp the timing pointer on the engine cowl in such positiontI1Ut the point, is n e a r the lending l ' l< : lgeof the scale previously at-tached. Jot the reading- on the timing scale.

(3) "'ontimle to turn the crankshaft in the same direction untiltJ1C top center indicator has zone past nnd returned to the zero mark.Note the readin r, . on the tim in g sea Ie.

1:-...... r--------AOJUSTltlG WRENCHr--~rIr!\\--------- CLAMPING SCREW

.----4 H-\\ -li :\ ---- ---- - CLAMPIr.lG WRENCH

,-------AOJUSTlIIIG SCREW

r-------ROCKER ARM

ROCKER ROLLER

GAGE

VALVE STEM

I' ..'

(4) Turn the erunkshaft backward about one-quarter of a revo-Iution !U1d then turn it forward until the timing pointer indicates itpoint on t he timing scale midway between he two readinzs pre-viously obtained, The .No.1 piston is now on the top dead center.

(5) Readjust the timiuz pointer on the cowl so that it indicatesexactly zero on the timing scale.d. Loosen the 0.9 cylinder intake valve clamping screw on rocker

arm and turn the adjusting screw until the thread is flush with therocker a rm.

7 4

MED M 'l'ANKS' M3 1 M3Al, AND M3A2

r-~~------AOCKER AR~

.91_---:: WASHER

HUB t lU l

PUSH RO ..

~AOJUSTING SCREW

75

TM )- linUe)


39/82

TM 9-75060-61 ORDNAl'


40/82

TM 9-75061-62 ORDNAJ\TCE MA N'rENANCE

reach the drain plug, a l%-inch pipe plug in the floor located beneaththe drain plug must be removed, To drain the horizontal tank,remove the circular plate located at the rear and bottom of sponson,and remove drain plug.c. Replacem. nt.-Fuel tanks will be replaced when excess ru t i

present or when leaks develop. Fuel tanks may be removed asfolJows:

(1) T ertioai tal1le..-(a) Drain tanks,(0) Remov front top pluto,

(0 ) Remove bottom plate at bottom of engine.(d ) Remove bulkhead brackets on each side.(e) Disconnect fuel line connections.(I) Screw out shut-off valve.(g ) Lift out tank.(2) Horizontal tan.7cs.-(a) Drain tanks.(b) Disconnect zas lines and screw out s

tm9-750mediumtanksm3m3a1andm3a2

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