TM 9-1727D Transfer Unit for Light Tanks M5, M5A1 and 75-Mm Howitzer Motor Carriage M8 1943

8/12/2019 TM 9-1727D Transfer Unit for Light Tanks M5, M5A1 and 75-Mm Howitzer Motor Carriage M8 1943

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~ ~ TM 9-1727DRESTRICTED

WAR DEPARTMENTTECHNICAL MANUAL

~ORDNANCE MAINTENANCE

TRANSFER UNIT FOR LIGHT TANKS M5, M5AI,AND 75-MM HOWITZER MOTOR CARRIAGE M

APRIL 28, 1943

FOR ORDNANCE PERSONNELONL Y


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1M 9-17270RESTRICTED

TECHNICAL MANUAL LNo. 9-17270 r WAR DEPARTMENTWashington, April 28, 1943ORDNANCE MAINTENANCE

TRANSFER UNIT FOR LIGHT TANKS MS, MSA1,AND 7 S-MM HOWITZER MOTOR CARRIAGE M8

Prepared under the direction of the. Chief of Ordnance

(

with the cooperation of the Cadilac Motor Car Division.,General Motors Corporation)

CONTENTSParagraphs . Pages

SECTION I. Introduction...................... 1-3 1-6II. Transfer unit .... . . . . . . . . . . . . . . .. 4-23 7-1-95,

III. References ...................... 24-25 196INDEX ...................................... 197-201

...


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TM 9-17270'-3ORDNANCE MAINTENANCE-TRANSFER UNIT FOR LIGHT TANKSM5~ M5Al, AND 75-MM HOWITZER MOTOR CARRIAGE M8

Section IINTRODUCTION

ParagraphPurpose and scope .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1Description of vehicles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .. 2References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 3I. PURPOSE AND SCOPE.

a. TM 9-1727D is published for the information and guidance ofall ordnance personnel charged with the maintenance and overhaulingof Light Tanks MS, MSAl, and 7S-mm Howitzer Motor Carriage MS.It includes complete maintenance information on the transfer unit. Theother technical manuals covering these vehicles are listed in section III.2. DESCRIPTON OF VEHICLES.a. The Light Tanks MS and MSAI are armored, full-tracklayingcombat vehicles, each carrying a crew of four men. They are eachpowered by two liquid-cooled, 90-degree, V-type, 8-cylinder engineslocated in the engine compartment in the rear of the hull. Power istransmitted to the final drives and tracks through two Hydra-Matictransmissions, two propeller shafts, a two-speed, step-down transfer unit,and the controlled differential fig. 4). \

\b. The Motor Carriage M8 fig. 3) is an armored, full~tracklaying,self-propelled mount for a 7S-mm howitzer. It carries a crew of fourmen. It is powered by the same engines, transmissions, and power trainas the Light Tank MS.3. REFERENCES.

a. Section III of this volume lists all techqical manuals, standardnomenclature lists, and other publications relative to the materiel de-scribed herein.

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1M 9-172703

INTRODUCTION

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TM 9-172703

ORDNANCE MAINTENANCE-TRANSFER UNIT FOR LIGHT TANKSM5, M5Al, AND 75-MM HOWITZER MOTOR CARRIAGE M8

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1M 9-172704Section II

TRANSFER UNITParaCJraph

Description ............................... . . . . . . . .. .. 4Operation ................,........................... 5Tabulated data and specifications ........................ 6Allocation of maintenance duties by echelons. . . . . . . . . . . . . . . 7Inspection in vehicle .... '.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Trouble shooting' . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Service in vehicle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 10Replacement of components in vehicle. ... .. . .. . .. . . . ... .. .. 11Removal of transfer unit from vehicle. . .. . ... .. . ... ... . . .. 12Disassembly of transfer. unit ..................... . . . . . . . . 13Disassembly of transfer unit components. . . . . . . . . . . . . . . . . . . 14Inspection and repair of transfer unit and components. . . . . . . . 15Assembly of transfer unit components. . . . . . . . . . . . .. . . . . . . . 16Assebly of transfer unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Installation of transfer unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Limits and tolerances .................................. 19Cfor-que tightnesses ..................................... 20Special tools ........ . . . . . . . . . . . . . . . . . .'. . . . . . . . . . . . . . .. 21Preparation for extreme conditions....................... 22Packing and shipping . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . 234. DESCRIPTON.

a. The transfer unit performs two distinct functions. It tak~s thepower of the two engines, delivered to the transfer unit by he propellershafts, Rnd combines these two power flows into one. It also provides atwo-speed, hydraulic-controlled gear reduction which, combined withthe reductions in the transmissions, permits a total of six forward speedsand one reverse speed.

b. The transfer unit is located in the front end of the vehicle, mountedon a flange on the rear of the controlled differential housing (fig. S).c. The' transfer unit case is composed of two sections, a large maincase at the front which contains the mechanism for the gear reductionunit and the hydraulic control parts, and a smaller case at the rear whichcontains the connector unit by means of which the torque from the twopropeller shaft-s is combined into the one transfer unit main shaft.

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1M 9-172705ORDNANCE MAINTENANCE-TRANSFER UNIT FOR LIGHT TANKSM5, M5Al, AND 75-MM HOWITZER MOTOR CARRIAGE M8

1M 9-172705TRANSFER UNIT

PUMP, OIL

COVER, LOW GEAR SERVOSPRINGS,LOW GEAR SERVO

\l COVER, REVERSE SERVOHt SPRING, REVERSE SERVO- II~ :ERVO, REVERSEI ' rr

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IA PD 8734RA PD 8735Figure 7 - Transfer Unit - Cross Section at Low Gear Servo~at a speed less than that of the second center gear. The planet gears ofthe second planetary train accordingly rotate with these gears and atthe same time walk around the second center gear at an over-all gearreduction of 2.37 to 1. Since the output shaft is attached to the planetcarrier of the second planetary gear train, this is the gear reduction ofthe transfer unit.

b. Upshift. When the vehicle speed is such that the transfer unitupshifts, oil pressure is applied to the release side of the low gear servo.This oil pressure overcomes the apply pressure of the springs and assures.the gradual release of the low gear band from the brake drum. At thesame time that this occurs, oil pressure is also delivered to the clutchapply pistons and the clutch is applied (fig. 11). Detils of the hydraulicmechanism whereby this is accomplished are given in paragraphS j.12

Figure 8 - Transfer Unit - Cross Section at Reverse Servoc. Direct Drive. When the above action'has taken place, the entieplaneta gear train revolves as a unit and the rotation of the propellershafts is transmitted without reduction to the pinion on the output shaft.d. Reverse. When the selector lever for the Hydra-Matic transmis-sions is moved into the reverse position, a connection from this lever tothe transfer unit releases a mechanical latch holding the reverse servoapply spring in the released position. This spring, being freed, appliesthe reverse servo; At the same time, a valve is repositioned to relieve theoil pressure that hlso holds the reverse servo in the released potion.

The flow of power to the transfer unit is exactly the same as previouslydescribed except that the diection of rotation is reversed. The reverseband application is necessary to provide self-energizing action with thisdirection of rotation, and Doth bands act to hold the dr from slipping(fig. 12).

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1M 9-172705

ORDNANCE MAINTENANCE-TRANSFER UNIT FOR LIGHT TANKSM5, M5Al. AND 75-MM HOWITZER MOTOR CARRIAGE M8

RA PD 8736Figure 10 Transfer Unit in Reduction

RA PD 8737Figure ii Transfer Unit in Direct Drive

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1M 9-172705

TRANSFER UNIT

CLUTCH RELEASED

RA PD 8738Figure 12 Transfer Unit in Reverse

e. Hydraulc Control System. The timing of the hanges in gearratios either upshifting or downshifting is the function of the hydrauliccontrol system. This system is basically one of carefully balanced valvesto provide a precise relationship between the velocity of the vehicleand the performance demands of the driver as expressed by the presureon the accelerator. The hydraulic control units ilustrated in dia-grammatic form in figure 13, consist of the following: a compound oilpump connected to an oil pressure regulator a centrifugal-type governora control valve body containing the control valves and shift valves, andthe necessry connecting passages.

f. The governor and oil pump are mounted on a carrer on the right-hand side of the transfer unit case and are driven by the same shaft,which in turn is geared to the output shafL With this arrangement, theoil pump delivers oil only when the vehicle is in motion, at which time itprovides both the oil pressure for operating the control mechanism andthe oil for lubricating the gears and bearings of the transfer unit and thecontrolled differentiaL.g. The oil pressure supplied by the pump for the control mechanismis maintained between 85 and 90 pounds by means of the oil pressure

regator. This pressure is directed through control. valves to apply or7

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TM 9-172705ORDNANCE MAINTENANCE'- TRANSFER UNIT FOR LIGHT TANKSMS. MSAl, AND 7S-MM HOWITZER MOTOR CARRIAGE M8

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VALVE, OIL PRESSURE REGULATOR ~-~RA PD 8707

Figure i 3 - Hydraulic Conttol Systemrelea the bands and apply the clutch as required by the variousoperating conditions.

h. Reductions. As son as the vehicle starts to move forward oilunder presure is delivered to the control valve body. At the same timeths oil under pressure is directed to the gov~or in such a way thatprssure is built up and applied to oppose fue centrifugal force actingon the governor weight.i. As the vehicle speed increase,s, the centrifugal force acting on theg,overor weight also increases and repositions the governor valve, so

tht a varable pressure from the governor is fed back to the controlvalve boy. This pressure is directed toone end of the shift valvetendig to force it to the open position and upshift the transfer unit fromreuction to diect drive. Spring pressure and thottle pressure on theopposite end of the valve act against the governor pressure and tend tooppo the upshift. Thus the speed at which the upshift occurs isdeterined by the relation between thottle pressure and governorpressure (fig. 14).j. Upshift. As the speed af the vehicle increases furher, the oil pres-sue from the governor becomes great enough to overcome the opposingspring and throttle pressure on the shift valve, causing it to move to itsopen position. The movement of the shift valve causes oil to be directed

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TM 9-172705TRANSFER UNIT

r- Oil Pressure to Bandelease and Clutch Apply

Throttle Spring OpposesGovernor Pressure IRA PD 9200Figure 14 - Opposing Forces on Shiff Valve

to the clutch apply pistons and also to the release side of the low gearservo, thus applying the clutch and releasing the low gear band., Thisarrangement causes the planetary gear system to rotate as a unit and, theshift to direct drive is completed.

k. Downshift. When the speed of the vehicle is reduced to a pointwhere the spring and throttle valve pressure against the ~shift valve inthe valve body overcomes the oil pressure directed, against it by thecentrifugal governor, the shift valve moves back to the closed position.This action cuts off oil pressure to the release section of the low gearservo allowing the springs in the servo to reapply the low gear band. Atthe same time, the oil pressure against the clutch relay valve in the valvebody is cut off, which in turn permits release of the pressure applyingthe clutch. The clutch release springs then release the clutch at thesame ~ime as the band is being reapplied, thus putting the transfer unitagain in reduction. '

I. LO Range. When the control lever on the transfer unit is movedto the LO position, a valve in the control valve body is manuallymoved into' a position where the full pressure from thi: oil pump isdirected against the shift valve. This fore, together with the springpressure against the shift valve, is great enough so that the pressure fromthe governor cannot move the valve to its open position. Thus noupshift can take place. Oil pressure is also directed to the low gear servoin such a manner as to assist the springs in holding the band tight onthe drum.

m. If the transfer unit control lever should be moved to the' LOposition while the vehicle is being driven at high speed, the governorpressure existing at these high speeds wil be high enough to oppose adownshift until the speed of the vehicle has been reduced to a point'where the downshift can be made without damage to the mechanism.'9


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1M 9-172706-7ORDNANCE MAINTENANCE-TRANSFER UNIT FOR LIGHT TANKSMS, MSAl, AND 7S.MM HOWITZER MOTOR CARRIAGE M86. TABULTED DATA AND SPECIFICATIONS.Connector gear ratio ....... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 to 1Connector gear type ................................... HelicalGear ration in reduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.37 to 1Lubrication . . . . . . . . . . . . . . . . . . . . . . . .'. . . . . . . . . . Oil under pressureNumber of speeds forward ....................... . . . . . . . . . .2Number of speeds reverse ................................... 1Shift control ................;...................... HydraulicType of gearing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Compound planetarySerial number. ... ... .. . .. . . . . .. ... .. . .. .; . . . .. . . .IGTI and up

(Located on the flat machined surface between thelow gear and reverse servos)7. ALLOCATION OF MAINNANCE DUTIES BY ECHELONS.a. Definitions. Echelons and words as used in this list of maintenanceallocations are defined as follows:SECOND ECHELON: Line organization regiments, battalions, companies

(first and second echelons).THIRD ECHELON: Ordnance light maintenance companies, ordnancemedium maintenance companies, ordnance divisional maintenancebattlions, and post ordnance shops.FOURTH ECHELON: Ordnance heavy maintenance companies and ser-vice command shops.FIFTH ECHELON: Ordnance base regiments, ordnance bases, arsenals,manufacturers' plants.

SERVICE:Including pre-ventive mainte-nance) (par. 23a 1) and 2)AR 850-15 (10-6-42) )

REPLACE:(par. 23 a (4)AR 850-15 (10-6-42) )REPAIR:(par. 23 a (3)and (5), in part,AR 850-15 (10-6-42) )

/onsists of servicing, cleaning, lubricating, tighten-ing bolts and nuts, and making external adjust-ments of subassemblies or assemblies and con-trols.

Consists of removing the part, subassembly or as-sembly from the vehicles and replacing it with anew or reconditoned or rebuilt part, subassemblyor assembly, whichever the case may be.

Consists of making repairs to, or replacement ofthe part, subassembly or assembly that can beaccomplished without completely disassemblingthe subassembly or assemblies, and does not re-quire heavy welding, or riveting, machining,fitting and/or alining or balancing.

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1M 9-172707-8TRANSFER UNIT

REBUILD:(par. 2 a (5),in part, and (6),AR 850-15 (10-6-42) )

Consists of completely reconditioning and replacingin serviceable condition any unserviceable part,subassembly or assembly of the vehicle, includ-ing welding, riveting, machining, fitting, a1ining,balancing, assembling,' and testing.b. Maintenance AlloCttions.

NOTE: Operations allocated wil normally be performed in the echelon indicatedby X . Operations aliocated to the echelons as indicated by E may beaccompli~hed by the respective echelons in emergencies only.ECHELONS2nd 3rd 4thNIT, TRANSFER, ASSEMBLY

Bands, transfer unit-adjust .................Bands, transfer unit-replace or: repair (reline) . .Body, control valve-replace ................Body, control valve-repair .................Body, control valve-rebuild ................Unit, transfer, assembly-replace ...,.........Unit, transfer, assembly~repair ....,.........Unit, transfer, assembly-rebuild .............

5thX ?

E XXX

E XXE X

E X

8. INSPECTION IN VEHICLE.a; Purpose. Inspections by ordnance personnel are a follow-up andcheck on organizational maintenance, inspections and servicing. Theseinspections determine whether or not the vehicle should be continued inservice or withdrawn from operation for overhauL.b. Inspection Form. TNar Department 0.0. Form No. 7351 Pre-ventive Maintenance Operation and Technical Inspection Form forFull-Track Vehicles, is the standard and offcial form for recording theinspection of all motor vehicles, including combat vehicles of the Ord-nance Department. The extent to which use is made of this form ormodification thereof depends entirely ,on the technical abilty of avail-able personnel, the time factor, and the test shop equipment available.c. Equipment Required.CLEAN RAGSFLASHLIGHT GAGE, pressure, 0 to 100-lbd. Visual Inspection Procedure. The following periodic inspections

of the transfer unit in the vehicle are prescribed.1) DAILY(a) Check oil leveL. NOTE: Whenever checking oil level, vehicleshould be on level ground.21


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TM 9-172708

ORDNANCE MAINTENANCE-TRANSFER UNIT FOR LIGHT TANKSMS, MSAl, A ND 7S.MM HOWITZER MOTOR CARRIAGE M8(2) AFTER 250 MILES OF OPERATION.( s) Check oil leveL.(b) Check oil cooler connections for leaks.(c) Check entire transfer unit for leaks at any possible point.(3) AFTER 3,000 MILES OF OPERATION.(s) Drain oil in transfer unit, flush and refill (par. 10 b).(b) Check and adjust bands (par. 10 c).e. Operating Inspection. Check the transfer unit under actual operat-ing conditions and notice whether it is functioning properly, at the

various shift speeds.( 1) SHIFT SPEEDS. Check to make sure the transfer unit upshifts anddownshifts in the proper speed ranges, as follows:(s) Selector Lever in DR .Upshift Light, Throttle Full Throttle

4th to 6th........ .1,600 to 2,000 rprn....,.. .3,400 to 3,900 rpmDownshIft

6th to 4th...... ... 460 to 650 rpm.... .. .. 925 to 1,125 rpm6th to 5th.. .. .. .. . . .. . . .. .2,100 to 2,400 rpm

(b) Selector Lever Moved to LO .Transfer unit should downshift 6th to 4th, no higher than 1,600 to1,800 rpm.'f. Checking Transfer Unit Oil Pressure. Five oil pressures in thetransfer unit hydraulic control system may be checked without removingthe transfer unit from the vehicle. ~e are pump pressure, lubricationpressure, clutch apply pressure, governor pressure (except on earlytransfer. units) and low servo apply pressure in low. Whenever the trans-fer unit is not operating properly, these oil pressures should be checkedin accordance with the trouble-shooting outline in paragraph 9. The

pressures are checked as follows:(1) EQUIPMENT.ADAPTER, pipe plug, l/-in.ADAPTER, pipe plug, -in.GAGE, pressure, 0 to 100-lbSCREWDRIVERWRENCH, open-end, -in.(2) CHECK PUMP PRESSURE.ADAPTER, pipe plug, l/-in.

GAGE, pressure, 0 to 100-lb

WRENCH, open-end, I-in.WRENCH, soket-head setscrew, o/6-in.WRENCH, socket-head setscrew, %-in.

WRENCH, socket-head setscrew, o/6-in.WRENCH, open-end, I-in.On early transfer units, remove l/-inch pipe plug on right side of casejust behind speedometer driven gear adapter, using o/6-inch socket-head

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1M 9-172708

TRANSFER UNITPLUG, CLUTCH APPLYPRESSURE CHECK

80-90 LBS.PLUG, LOW SERVOAPPLY PRESSURE CHECK

80-90 LBS.

RA PI) 9384Figure J 5 - Plugs for Oil Pressure Checks

set screw wrench (fig. 15): On later type units, remove the oil pressuregage unit which is installed at this point (I-in. open-end wrench). Co-nect pressure gage and adapter at opening from which plug or gage unitwas removed. Start vehi.cle and drive at any speed above two miles perhour. The pump pressure should be from 85 to 95 pounds at these spsin any gear. If pressure is less than this amount, check for cause of'condition, as outlined in paragraph 9. Remove pressure gage andadapter and install plug or gage unit.

(3) CHECK LUBRICATION PRESSURE.ADAPTER, pipe plug, -in.GAGE, pressure, 0 to 100-lb SCREWDRIVRWRENCH, socket-head 'setscrew, %-in.

Remove -inch pipe plug (large plug) at top of transfer unit rearcover (fig. 15). Connect pressure gage and adapter to 'transfer case rearcover where plug was removed. Start vehicle and drive at approximately10 miles per hour. The lubrication pressure should be four p~)Unds mini-mum at this speed in any gear. NOTE: The transfer unit should be

23

1


14/102

1M 9-172708ORDNANCE MAINTENANCE - TRANSFER UNIT FOR LIGHT TANKS

MS, MSAl, AND 7S-MM HOWITZER MOTOR CARRIAGE M8thoroughly warmed up to normal operating temperature when this checkis made. If pressure is less than this amount, check for cause of conditionas outlined in paragraph' 9. Remove pressure gage and adapter, andinstall ';-inch pipe plug.

( 4) CHECK CLUTCH ApPLY PRESSURE.ADAPTER, pipe plug, li-in. SCREWDRIVERGAGE, pressure, 0 to 100-lb WRENCH, socket-head setscrew, %6-in.

Remove li-inch pipe plug (small plug) at top of transfer unit rearcoyer (fig, 15). Connect pressure gage and adapter to transfer U?it rearcover where plug was removed. Start vehicle and increase speed untiltransfer unit shifts from reduction to direct drive. When the shift is ,imade, the clutch apply pressure should be not more than five pounds lessthan the pump pressure. If pressure is less, check for cause of co~dition,as outlned in paragraph 9. Remove pressure gage and adapter, andinstall plug in transfer unit rear cover.

(5) CHECK GOVERNOR PRESSURE.ADAPTER, pipe plug, li-in. WRENCH, socket-head setGAGE, pressure, 0 to 100-lb screw, %6-in.

Transfer units of early production did not have provision for makingthis check. On later transfer units, proceed as follows: remove thesocket-head set screw wrench located toward the rear of the center ofthe oil pump and governor carrier (fig. 15), and connect pressure gageand adapter at opening. Drive ~cle with transmission and transferunit selector levers in DR position. At 1,700 revolutions per minute,pressure should be 25 to 30 pounds; at 3,400 revolutions per minute;it sfiould be 70 to 80 pounds. Reduce vehicle speed, shift transfer unit to LO range, and increase speed to 3,000 revolutions per minute. Pres-sure should then be between 50 and 60 pounds. If pressure is less thanthese amounts, check for causes of conditions as outlned in paragraph 9.Remove pressure gage and install plug.

(6) CHECK Low SERVO ApPLY PRESSURE.ADAPTER, pipe plug, ';-in. WRENCH, socket-head setSCREWDRIVER screw, ';~in.WRENCH, open-end, 3l-in.Reriove adjusting plug from low gear servo cover, using screwdriveror socket-head set screw wrench. Connect gage and adapter to plug open-

ing. Drive vehicle with transmission and transfer unit levers in 'DR"position at a sped above 22 mile per hour. Move transfer unit lever to LO position, release accelerator, and let vehicle slow down. Trans-mission wil downshift to 5th at about 22 miles per hour; transfer unitwil downshift to 4th at about 20. After transfer unit downshifts,

24

1M 9-172708-9TRANSFER UNIT

accelerate engines to 2,200 revolutions per minute and check pressure ongage, which should be 85 to 95 pounds. If pressure is low, check forcause of condition as outlned in paragraph 9. Remov pressure gageand install plug.(7) RELATION TO TROUBLE SHOOTING. The Trouble Shooting sec-

tion (par. 9) of this manual should be studied closely in order thatvarious trouble symptoms may be recognized during the operatinginspection.9. TROUBLE SHOOTING.

a. When checking the transfer unit for possible malfunctioning, thefirst job is to determine definitely that the condition at hand is due tothe transfer unit and not to other related units. The transmissions, forexample, are so closely related to the transfer unit that often, when thetransfer unit is suspected of not operating properly, the original causemay lie in the transmissions. After the vehicle has been checkoo underatul operating conditions and the fault determined, compare the con-dition with those listed in the chart below. When a comparable conditionis found, repeat the test at least two more times to make sure that allsymptoms agree with the condition on the chart. NOTE: Do not removethe transfer unt until the condition is definitely determined.

b. Transfer Unit Does Not Respond to Selector Lever Position. . d hi' "LO" 't')(wil not upshift in DR posItIon or owns t in pOSI ion .Possible Cause Possible RemedyManual control valve in valve Remo~e valve body cover arid en-body not engaged with button gage manual control valve withon control lever. lever.

c. Transfer Unit Slips in 1st, 2nd, 3rd and 4th Speeds, but Oper.ates Satisfactorily in 5th and 6th Speeds.Low gear band not holding clue to Adjust band.improper adjustment.

d. Transfer Unit Drives Vehicle in 1st, 2nd, 3rd, and 4th Speeds,but Both Engines Race in 5th and 6th Speeds Due to Clutch Slipping.No oil pressure to clutch pistons. Check oil pressure as explained inparagraph 8 and repair or re-place units as requied.

Clea~ repair, or replace.ainshaft spacer oil seal rings inclutch drum broken or sticking.Clutch piston rings broken or, sticking.

Low pump pressure.Clean, repair, or replace.Clean, repair, or replace.

25


15/102

1M 9-172709ORDNANCE MAINTENANCE - TRANSFER UNIT FOR LIGHT TANKSMS, MSAl, AND 7S-MM HOWITZER MOTOR CARRIAGE M8

Possible CauseOil passages to clutch plugged.Oil leaks in oil passages to clutch.Oil leaks between valve body andspacer plate.Clutch plates scored or burned.

Possible RemedyClean, repair, or replace.Clean, repair, or replace.Clean, repair, or replace.Replace plates.

e. Transfer Unit Slips in Reverse.Reverse band not holding. Check reverse band adjustment.Reverse band released due to re- Check adjustinent of control link-

lease pressure or release latch age to reverse servo.not being tripped. Remove reverse servo and checkoperation of release mechanism.Replace reverse servo.f. Transfer Unit Starts in Reduction but Shifts to Direct DriveImmediately After Vehicle is Put in Motion.Governor valve sticking in open Clean, repair, or replace governor.position.Clutch relay valve sticking in open position.Shift valve sticking in oped' posi-tion.

Cle~, repair, or replace valve bodyassnbly.Clean, repair, or replace valve bodyassembly.

g. Transfer Unit Wil Not Upshift into Direct Drive for 5th or 6thSpeeds.Manual control valve not engagedwith lever.Governor valve sticking in closed

position.Oil pressure leak in passages be- Clean, repair, or replace valve bodytween governor and valve body assembly.assembly.Governor plug or shift valve stick~

ing in closed position.CIl;tch relay valve sticking.Exhast downshift valve

in open position.Low oil pressure.sticking

Clean, repair, or replace valve bodyassembly.Clean, repair, or replace governor.

Clean, repair, or replace valve bodyassembly.Clean, repair, or replace vave bodyassembly.Clean, repair, or replace valve bodyassembly.Check oil pressures as explained inparagraph 8 and repair or re-place units as required.

26


Possible Cause Possible Remedyh. Tra:nsfer Unit Shifts into Direct Drive at Lower Vehicle SpeedsThan is Desirable. ,Improperly adjusted throttle valve Adjust throttle linkage.'linkage between front throttlerelay and transfer unit valvebody.

Governor valve sticking.Regulator plug in valve body stick-ing.Throttle valve in valve body stick-

ing.Low oil pressure.

Clean, repair, or replace valve bodyassembly.Clean, repair, or 'replace valve bodyassembly.Clean, repair, or replace valve body

assembly.Check oil pressures (par. 8). Re-pair or replace units as required.i. Transfer Unit Shifts into Direct Drive at Higher Vehicle Speeds. than Desirable.Improperly adjusted throttle valve Adjust thtottle linkage.linkage.Sluggish or sticking governor valve.

Regulator plug in valve body stick-ing.Sluggish or sticking governor plug Clean, repair, or replace valve body.or shift valve in valve body.Throttle valve sticking in open Clean, repair, or replace valve body.position.Sluggish or sticking clutch relay Clean, repair, or replace valve body.

valve hi valve body..High oil pressure.

Clean, repair, or replace governor.Clean, repair, or replace valve body.

Check oil pressure as explained inparagraph 8 and repair or re-place units as required.j. Transfer Unit Slips in Low Range When Using Engine as Brake,but Operates Satisfactorily on Pull.Low gear servo valve sticking in Clean, repair, or replace valve body. closed position.k. Transfer Unit Downshift from Direct Drive, to Reduction with. Wide Open Throttle Very Severe, or Engines Race MomentarilyWhen Shift Occurs.Accumulator valve or throttle Clean, repair, or replace valve body.downshift valve in valve bodysticking.27


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:.- r.. ..ORDNANCE MAINTENANCE - TRANSFER UNIT FOR LIGHT TANKSMS, MSAl, AND 7S.MM HOWITZER MOTOR CARRIAGE M8

Possible CauseLow oil pressure.

Weak or broken oil pressure regu-lator spring.

Oil pressure regulator valve ingovernor and oil pump carriersticking.Oil pump loos on carrier.Defective gasket between oil pumpcarrier and spacer plate.Wom oil pump gears.Defective gasket between topspacer plate and transfer unitcase.Plugged oil lines in transfer unitcase.

II

Possible RemedyCheck oil pressure as explained inparagraph 8 and inspect forcause of condition until sourceis located. Repair or replaceunits as required.

Repair or replace.Repair or replace.

Tighten.Replace.Replace.Replace.

Clean, r~ir, or replace.

10. SERVICE IN VEIDCLE.a. Check Oil Level.

CLEAN RAGSMake sure vehicle is on level ground. Clean area around transfer unitoil filler- pipe. Remove gage indicator assembly and wipe plunger clean.Then return to filler pipe and push down until cap on indicator seatson filler pipe opening. Remove to check oil leveL. If necessary, addOIL, engine (seasonal grade).b. Change Oil. When changing oil in the transfer unit, it is neces-sary to also change oil in the controlled differentiaL.( 1) DRAIN OIL FROM TRANSFER UNIT AND CONTROLLED DIFFEREN-TIAL. CLEAN RAGS WRENCH, socket-head setDRAIN PAN, 10-gal capac- screw, o/6-in.ity WRENCH, socket-headWRENCH, socket, o/6-in. set screw, -in.Remove co~er plates on bottom of hull under transfer unit and con-trolled differential (o/6-in. socket wrench), and clean area around drain

28

TM 9-17270'0TRANSFER UNIT

BAND ADJUSTING GAGE B226839

RA PI) 9385

Figure J6 - Adiusling Low Gear landplugs. Place drain pan under three openings. Remove one drain plugfrom transfer unit (o/6-in. socket-head set screw wrench), and twoplugs from controlled differential ( -in. socket-head set screw wrench)and allow oil to drain into the drain pan. Clean magnetic drain plugs,and if excessive metal particles are present, investigate condition of units.

(2) REFILL TRANSFER UNIT AND CONTROLLED DIFFERENTIAL.WRENCH, socket, 6-in. WRENCH, socket-headWRENCH, socket-head set screw, -in.. set screw, o/6-in.

Position tiiee drain plugs in bottom of transfer unit ( 6-in. soket-head set screw wrench) and controlled differential (3,-in. socket-headset screw wrench) and tighten in place. Position three cover plates onbottom of hull and tighten in place (o/6-in. socket wrench). Fil transferunit with 28 quarts of OIL, engine (seasonal grade).c. Band Adjustments in V ehicle~ Two bands are used in 'the trans-fer unit: a low gear band (toward front of vehicle) and a reverse band

29


17/102

1M 9-1727010ORDNANCE MAINTENANCE - TRANSFER UNIT FOR LIGHT TANKSMS, MSAl, AND 7S-MM HOWITZER MOTOR CARRIAGE M8(toward rear of vehicle). The bands can be adjusted while the tra~sferunit is in the vehicle. Both bands should always be adjusted wheneverit becomes necessary to adjust one or the other. The low gear bandshould always be adjusted before the reverse band is adjusted.

( 1) EQUIPMENT.GAGE, feelerGAGE, low and reversetransit band adjusting,B226839SCALE, 6-in.

SCREWDRIVERWRENCH, -in.WRENCH, lh-in.WRENCH, Ilh-in.WRENCH, deep soket,o/6-in.

WRENCH, deep socket,1 i6-in.WRENCH, open-end,l1f-in.WRENCH, open-end,Ilh-in.WRENCH. socke~, lh-in.WRENCH, socket, o/6-in.WRENCH, socket, %-in.WRENCH, socket-head setscrew, -in.

(2) Low GEAR BAND ADJUSTMENT.(a) Chek Postion of Reverse Servo Piston. \

GAGE, low and reverse SCALE, 6-in.transit band adjusting, WRENCH, open-end,B226839 1i6-in.Before any adjustments are made, it is important to check the posi-tion of the reverse servo piston. To do this, remove the acorn plug on

the top of the reverse servo cover with a 1l/i'6-inch open-end wrench.The piston rod must be at least lh-inch above the top of the boss onthe servo cover. This is the released position. If the piston rod is in thisposition, proceed with step (6) below; if not, release the band eitherby installng band adjusting gage B226839 in top of rod and tighteningpressure nut unti piston rod is pulled up to at least lh-inch above topof boss, or by driving vehicle forward a few feet. J;lace the selector leverin any position other than REV ; this wil hold the piston rod in theproper position for adjustment procedure.

(b) InstaII Adjusting Tool in Low Gear Servo.GAGE, low and reverse WRENCH, -in. ortransi t band adjusting, WRENCH, socket-head set

B226839 screw, -in.Remove plug from low gear servo cover, and screw in gage until itbottoms in tapped hole in upper end of low gear servo piston rodTighten pressure nut on band adjusting gage until LO marke on gageis flush with top of pressure nut (fig. 16).30


(c) Check Low Gear Band Adjustment.GAGE, feeler SCALE, 6-in.GAGE, low and reversetransit band adjusting,B226839

Note position of pressure nut. It should be just clear of servo coverif the low gear band is adjusted properly. There should be from 0.002-inch to 0.005-inch clearance between pressure nut and servo cover. Ifpressure nut is tight against servo cover, low gear band is too loose.NOTE: If band adjusting gage is not available, adjustment can bechecked by measuring distance from boss on servo cover to, upper endof piston rod. This distance should be 1 inches (plus or minus 11:2 in.).(d) Remove Leg Guard and Adjusting Hole Cover.

WRENCH, socket, lh-in. WRENCH, socket, -in.WRENCH, socket, o/6-in.Remove assistant driver's leg guard by removing two mounting screws(o/6-in. and %-in. wrenches). Remove six screws and lock washers(lh-in. soket wrench) holding low gear band adjusting hole cover on

right side of transfer unit case, and remove cover and gasket.(e) Adjust Low Gear Band.GAGE, low and reverse

transit band adjusting,B226839Swing,back lock plate (fig. 16) which keeps the low gear band adjust-ing screw from tuing, and tighten adjusting screw (o/6-in. wrench).Continue tightening' adjusting screw until pressure nut on the bandadjusting gage is just lifting off low gear servo oover, or until rod end

is 1 inches below boss on servo cover, as explained in step (2) (a)above.

SCREWDRIVERWRENCH, o/6-in.

(f) Install Adjusting Hole Cover and Leg Guard.WRENCH, socket, lh-in. WRENCH, socket, %-in.WRENCH, socket, %6-in.Position low gear band adjusting hole cover and a new gasket on sideof screws and lock washers (o/6-in.'and %-in. socket wrenches). NOTE:Do not remove band adjusting gage from low gear servo until reverseband is adjusted.'(3) REVERSE BAND ADJUSTMENT.(a) Remove Plug in Reverse Servo Cover.GAGE, low and reverse WRENCH, deep socket,transi t band adjusting, l1f6-in.B226839

3'


18/102

TM 9-1727010ORDNANCE MAINTENANCE - TRANSFER UNIT FOR LIGHT TANKSMS, MSA1, AND 7S-MM HOWITZER MOTOR CARRIAGE M8UPPER MARK ON TOOL% ABOVE PRESSURE NUTPISTON ROD llABOVE BOSS ON

SERVO

BAND ADJUSTING TOOLNO. B-226839

''c,..,,c,,

RA PD 9224

Figure 17 - Adiusling Reverse Band

1M 9-17270'0TRANSFER UNIT

Be sure to check low gear band adjustment before proceeding withreverse band adjustment. Tighten pressure nut on band adjusting gageon low gear servo (installed in step c (2) above) until LO mark ongage is inch above pressure nut. Place the transmission selector leverin the REV. (reverse) position. Remove acorn plug' and gasket fromreverse servo cover (11f6-in. deep socket wrench).

(b) Check Band Adjustment. .SCALE, 6-in. WRENCH, 1 'h-in.Apply both steering brakes and lock with ratchets..Start both enginesand accelerate to 800 revolutions per minute with selector lever inreverse. Shut off engines. Check position of reverse servo piston rod.

Upper end of rod should be VB inch plus or minus 2 inch above topof the boss on servo cover when reverse band is adjusted properly.(c) Adjust Reverse Band and Instal1 Plu~.

GAGE, low and reverse WRENCH, deep socket,transit band adjusting, %6-in.B226839 WRENCH, open-end,SCREWDRIVER 1 'h-in.

If reverse band requires adjustment, remove reverse band adjustinplug (1 'h-in. open-end wrench) and copper gasket from top of transfcirunit case (fig. 17). Lift up lock plate that keeps reverse band adjustingscrew from turning, and tighten adjusting screw (%6-in. deep socketwrench) until servo piston rod is VB inch above boss on cover. NOTE:If band adjusting gage is not available to release low gear band, asexplained in step (3) (a) above, it wil be necessary to back off lowgear band adjustment and readjust low gear band after reverse bandadjustment is complete.

(d) Remove Band AdjustIn~ Ga~e, and Instal1 Plu~s on Low Gearand Reverse Servos.

GAGE, ,low and reversetransi t band adjusting,B226839SCREWDRIVERWRENCH, open-end,11f6-in.

Install reverse band adjusting plug and a new copper gasket ontransfer unit case (1'h-in. open-end wrench)~ Install acorn plug anda new gasket on reverse servo cover (11f6-in. open-end wrench). Losenpressure nut on band adjusting gage; then unscrew gage from low gearservo piston rod. Install plug in low gear servo cover (screwdriver' or1,-in. socket-head set screw wrench). '

33

WRENCH, open-end,1 'h-in.WRENCH, socket-headset screw, 1,-in.

S~:7.,;-.


19/102

1M 9-1727010ORDNANCE MAINTENANCE - TRANSFER UNIT FOR LIGHT TANKS,MS, MSAl, AND 7S-MM HOWITZER MOTOR CARRIAGE M8

RODS, THROTTLE C\OLRA PD 9379

Figure i8 - Transfer Unit and Transmission Control Linkaged. Linkage Adjustments.(1) DISCONNECT RODS AT SHIFT LEVER.PLIERSDisconnect rod between shift lever and transfer unit reverse seorelease lever at shift lever end (fig. 18). Place shift lever in REV , 'position (make sure that it is in detent position shown on quadrant bythe arrow), and disconnect rod at lower end of shift lever.(2) INSTALL INTERMEDIATE RELAY GAGE PLATE.GAGE, pin, throttle controls, GAGE, throttle, intermediateadjusting, set, A266522 relay, A266521InstaU intermediate relay ga-ge plate A266521 next to manual lever,and throttle lever on left ends of intermediate relay cross shafts. Install2 gage pins A266522 (long), through pinholes on intermediate relaythrottle and manual levers, and into holes in gage plate to lock leversin a fied position (fig. 19). '(3) ADJUST ROD AT SHIFT LEVER AND REMOVE INTERMEDIATE RE-LAY GAGE PLATE.GAGE, pin, throttle controlsadjusting, set, A266S22GAGE, throttle, intermediaterelay, A266s21Adjust length of rod disconnected from lower end of shift lever byloosening clevis lock nut (o/6-in. open-end wrench), and rotating cleviswith a pair of pliers until clevis pin slips into selector l,ever. CAUTION:Shift lever must be in REVERSE position. Install clevis pin and cotter

34

PLIERSWRENCH, open-end, o/~-in.

1M 9-17270'0TRANSFER UNIT

il

RA PD 9381

Figure i9 - Gage at Intermediate Relay

,key, and tighten clevis lock nut. Remove gage pins and gage plate fromintermediate relay.(4), ADJUST MANUAL ROD TO TRANSFER UNIT REVERSE SERVO.PLIERS WRENCH, open-end, o/6-in.While working in fighting compartment, move transmission andtransfer unit shift lever past REVERSE position (toward rear of

vehicle) as far as it wil go. Hold shift lever in that position while ad-justing length of rod from shift lever to reverse servo release lever. Whenclevis pin is inserted, the stop on reverse servo release lever should justcontact stop on servo body if rod is adjusted properly. Release shiftlever, install clevis pin and cotter key, and tighten clevis lock nut (%6-in.open-end wrench). .\ 35


20/102

1M 9-17270, '0ORDNANCE MAINTENANCE -TRANSFER UNIT FOR LIGHT TANKSMS, MSA1, AND 7S.MM HOWITZER MOTOR CARRIAGE M8

. ./

GAGE, TOOl NO. A266520

BRACKET, FRONTTHROTTLE RELAY

~ ..RA PD 9310Figure 20 - Gage at Front Relay

(5) INSTALL FRONT RELAY GAGE AT FRONT RELAY FOR THROTTLERODS.GAGE, thotte, front relay, PLIERS, A266s20 WRENCH, soket, o/6-in.

Remove four screws and washers holding left propeller shaft frontcover to supports and remove cover o/6-in. socket wrench). Disconnectthrottle rod tht connects front relay and intermediate relay - at frontrelay end (pliers). InstaIl front relay gage A266520 on lever and mount-ing bracket as shown in figue 20.

(6) ADJUST THOTTLE ROD FROM INTERMEDIATE TO FRONT RELAY.PLIERS WRENCH, open-end, o/6-in.Adjust the length of this rod by loosening clevis lock nut at front

relay end and rotating clevis until pin will slip into hole in lever.Install clevis pin, cotter key, and tighten lock nut (o/6-in. open-endwrench). Remove front relay gage.(7) ADJUST ACCELERATOR PEDAL ROD TO FRONT RELAY.PLIERS WRENCH, open-end, o/~-in.Measure vertcal distance from end of accelerator peal to floor of

vehicle. If distance is not six inches plus or minus 6 inch, disconnect36

1M 9-17270, 0.11

TRANSFER UNITrod from pedal to front relay at front relay end. Adjust length of rodby loosening clevis lock nut (o/6-in. open-end wrench) and rotatingclevis until proper distance is obtained when clevis pin is installed infront relay lever., Install clevis pin, cotter key, and tighten lock nut.

(8) ADJUST TRANSFER UNIT THROTTLE ROD.WRENCH, open-end, Yi6-in.Disconnect throttle rod from front relay to transfer unit relay attransfer unit relay end. Depress accelerator to floor, Adjust length ofthrottle rod by rotating clevis until clevis pin wil enter hole in transferunit relay, while holding relay forward until trunnion just begins tocompress spring on throttle valve relay rod. Tighten lock nut on clevis.e. Servicing Oil Cooler. The only attention required in theser-

vice of the oil cooler is keeping it clean and making sure that the oilpassges are unobstructed.(1) CLEAN OIL COOLER.Remove cooler as explained in paragraph 11 g. Drain, all oil fromcooler. Fil cooler with SOLVENT, dry-cleaning, and allow to standfor one-half hour. Shake vigorously to obtain maximum solvent action,drain, and dr with compressed air. If the cooler is not completely,cleaned by this process, fill the unit with a strong solution of SODA,caustic, or CLEANER, phosphate, and let it stand for 24 hours. Thesolution should be frequently agitated by steam, if available, or theUnit immersed in a tank of hot water for the entire 24-hour period.Drain the solution, flush thoroughly with water to remove all trace ofthe solution, and dry with compressed air. NOTE: It is advisable to

Clean oil cooler in cases where failure of the transfer unit as the result ofwear has necessitated replacement of the entire assembly, as metalparticles from the worn parts may have settled in the oil cooler.II. REPLACEMENT OF COMPONENTS IN VEHICLE.

a. Control Valve Body. The control valve body can be replacedwhile the transfer unit is in the vehicle.

(1) EQUIPMENT.PLIERSSOCKET, Yi6-in.SOCKET, lh-in.WRENCH, socket, Yi6-in., (2) REMOVE CONTROL VALVE BODY.

WRENCH, socket, lh-in.WRENCH, . socket-headsetscrew, 4-in.WRENCH, torque

PLIERS WRENCH, socket, lh-in.WRENCH, socket, Yi6-in.Disconnect throttle control rod from lever on control valve body'cover by removing cotter key, washer and clevis pin (pliers). Remove37

iI


21/102

Ii

1M 9-17270l'ORDNANCE MAINTENANCE- TRANSFER UNIT FOR LIGHT TANKSMS, MSA1, AND 7S-MM HOWITZER MOTOR CARRIAGE M812 screws and washers (1f-tn. socket wrench) holding control valvebody cover in position (fig. 44). NOTE: Do not remove screw oncover holding manual selector lever detent spring to cover. Pull con-trol valve assembly cover and gasket off transfer unit case. Removefive screws and washers holding control valve. body to ~pacer ontransfer unit case. Remove control valve body from spacer.

3) INSTALL CONTROL VALVE BODY.PLIERS WRENCH, socket-head setSOCKET, 6-in. screw, -in.SOCKET, 1f-in. WRENCH, torquePosition control valve body assembly on transfer unit case spacer.Make sure that manual control valve is in position. Install five controlvalve body mounting screws, tightening them to 10 to 12 foot-poundstorque tightness, Position control valv\ body cover gasket and coveron transfer unit case over valve body. Remove sight plug from controlvalve body cover ( -in. socket-head set screw wrench) and check tosee that button on end of select(lr lever shaft engages neck on end ofmanual control valve. If button and valve are not engaged, re~ove coverand reposition manual control valve, Install plug. Install nine sh~rt andthree long control valve body cover mounting screws and washers,tightening screws to 15 to 18 foot-pounds (torque wrench with 1f-in.socket). Connect throttle control rod to lever on cover and install/clevispin, washer, and cotter key (pliers).

b. Low Gear Servo.( 1) EQUIPMENT.GAGE, low and reverse

transit band adjusting,B226839SCREWDRIVERWRENCH, open-:nd, o/6-in.WRENCH, socket, 1f-in.

2) REMOVE Low GEAR SERVO.SCREWDRIVER WRENCH, open-end,o/6-in.WRENCH, socket, 1f-in.Remove six long screws and lock washers holding low gear ~rvo totransfer unit case (il-in. socket wrench). CAUTION: Do not removetwo low gear servo cover mounting screws. These are the two screwsindicated in figure 40. Grasp low gear servo with both hands and pulloutward until mounting boss on servo body clears case. Remove servoand gasket.

3) INSTALL Low GEAR SERVO.GAGE, low and reverse WRENCH, socket, 1f-in.transit band adjusting,B226839

38

1M 9-1727011

TRANSFER UNITInstall gage B226839 through hole in top cover of low gear servo,

sCrewing end of pressure screw on tool into threaded end of piston rod.Tightn pressure nut until it contacts top cover of low gear servo. Installlow gear servo gasket on servo body and place servo in mounting holein transfer unit case. Line up servo body mounting screw holes withholes in case and see that yoke on end of low gear servo piston rod istured so that open end of yoke is toward outside of case. Hook lowgear servo piston rod yoke into pin on actuating lever. Wrap low gearband to faciltate installation of servo. Tighten pressure nut on gageB226839, and at the same time push servo into transfer unit case. Whenservo is drawn up close enough to transfer unit case, install six mountingscrews and lock washers (1f-in. 'socket wrench). Adjust low gear bandas explained in paragraph 10 c (2) above. -c. Reverse Servo.

1) EQUIPMENT.GAGE, low and reversetransit band adjusting,B226839SCREWDRIVER

WRENCH, l1f-in.WRENCH, deep socket,o/6-in.WRENCH, socket, 1f-in.

2) REMOVE REVERSE SERVO.SCREWDRIVER WRNCH, socket, 1f-in.WRENCH, l1f-in.WRENCH, ,deep socket, o/6-in.

Trip reverse servo latch by pullng release lever up against stop onservo cover. Remove six long screws and lock washers holding reverseservo to transfer unit case (1f-in. socket wrench). CAUTION: Do notremove two short screws holding reverse servo cover to servo body.NOTE: To prevent servo from sticking in case, trip reverse servo latchby pullng release lever up against stop on servo cover. Grasp reverse

i, servo with both hands, and pull servo out until mounting bos on servoclears transfer unit case.

(3) A new type revrse servo is being used beginning with transferunit No.1 GT4996. This new type servo can be identified by the two1f-inch socket-head pipe plugs on the side of the servo body below theouter exhaust valve lever in the place of one on the first type servo.The basic difference in the second type servo is the. us of a spring-loaded sliding check .valve instead of a ball check valve. Except forthe two items above, the two typs of servos are the same and areinterchangeable as complete units. On the second type servo the checkvalve and valve spring can be removed from the servo body by loosen-ing the set screw. On the first type servo the ball-check valve could notbe removed.

39

1M 9-17270 1M 9-17270


22/102

ORDNANCE MAINTENANCE-TRANSFER UNIT FOR LIGHT TANKSMS, MS1, AND 7S-MM HOWITZER MOTOR CARRIAGE M8

(4) INSTALL REVERSE SERVO.GAGE, low and reversetransit band adjusting,B226839

WRENCH, socket, 'h-in.Install gasket over reverse servo body and insert reverse servo incase. See that yoke on end of rod has open face toward outside of case,and hook over pin in actuating lever. Install gage B226839 into threaded

end of reverse servo piston rod through hole in servo cover. Tightenpressure nut on tool until it contacts reverse servo cover. Tightenpressure nut, at the same time pushing servo into case. Install sixscrews and lock washers holding reverse servo to transfer unit case('h-in, socket wrench). Adjust reverse band as explained in paragraph10 c (3). \d. Carrier Assembly.(1) EQUIPMENT.CLEAN RAGSPAN, drain, 10-gal capacityWRENCH, open-end, o/6-in.WRENCH, socket, 'h-in.

WRENCH, socket, o/6-in.(2) REMOVE CARRIER ASSEMBLY.

WRENCH, socket, %-in.WRENCH, socket-bead setscrew, o/6-in.WRENCH, socket-head setscrew, %-in.CLEAN RAGS WRENCH, socket %-in.PAN, drain, 10-gal capacity WRENCH, socket-head setWRENCH, open-end, o/6-in. screw, o/6-in.WRENCH, socket, 'h-in. WRENCH, socket-head set

WRENCH, socket, o/6-in. screw, -in.Drain only transfer unit oil as explained in paragraph 10 b but notcontrolled differential oiL. Remove two bolts holding right-hand leggurd (o/6-in. and%-in. socket wrenches) and remove guard. Remove14 screws and lock washers holding oil pump and governor carrier totransfer unit case (o/6-in. socket wrench). Remove oil pump andgovernor carrier, with pump and governor attached, from transfer unitcase, and remove carrier gasket.(3) INSTALL CARRIER ASSEMBLY.WRENCH, open-end, o/6-in. WRENCH, socket-head setWRENCH, socket, 'h-in. screw, o/6-in.

WRENCH, socket, o/6-in. WRENCH, socket-head setWRENCH, socket, -in. screw, -in.Install a new gasket on oil pump governor and carrier assembly andposition carrier on transfer unit case, meshing speedometer driven gear40

11TRANSFER UNIT

and oil pump idler gear. Install 14 screws and lock washers ho1cingcarrer to transfer unit case (o/6-in. socket wrench). Install right-handleg guard (o/6-in. and, %-in. socket wrenches). Fil transfer Ut withrequired amount of OIL, engine (seasonal grade).e. Replace Governor..(Refertopars.13b (6), 14e (1), 16 f (5), and 17 e (5)).f. Replace Oil Pump.

(Refer to pars. 13 b (6), 14 e (1), 16 f (5), and 17 e (5) ).g. Oil CooJer Assembly, Hoses, and Lines.(1) EQUIPMENT.SCREWDRIVERWRENCH, open-end, 'h-in.

WRENCH, open-end, o/6-in.WRENCH, open-end,1 i-in.WRENCH, open-end, 11;-in.

(2) REMOVE OIL COOLER.(a) Remove Fan Shrouds.WRENCH, open-end,'h.:in.WRENCH, socket, o/6-in.Remove center screw on engine compartment rear doors so that

deflector (M5Al and M8) can be swung up and hooked over clip onrear hood. Next, remove screws holding doors closed, and open doors(%-in.socket wrench). CAUTION: Turn master battery switch toOFF position. Remove bolts holding clamps on exhaust outlet pipes('h-in. open-end wrench) and remove the pipes. Remove three screwsfrom seal around each carburetor intake pipe (%6-in. socket wrench)and slide seals toward rear. Remove screws holding fan shrouds (o/6-in.socket wrench) and remove shrouds.(b) Remove Engine Fan, Fan Belt, and Bracket.WRENCH, socket, lo/6-in.Remove two nuts from fan bracket mounting studs and remove fan,fan, belt, and bracket.(c) Lower Oil Cooler.WRENCH, socket, 'l6-in.Lift out bulkhead' doors and remove four nuts and bolts holdingfront end f oil cooler to shroud which is mounted underneath andbetween radiators (fig. 21). Work throug engine compartment reardoors and remove four nuts and bolts holding rear end of oil, coolerto shroud. Oil cooler may now be lowered to rest on top of upperrear relay cross shaft.

WRENCH, socket, o/6-in.WRENCH, socket, 'l6-in.WRENCH, socket, 'h-in., WRENCH, socket, o/6-in.WRENCH, socket, %-in.WRENCH, socket, lo/6-in.WRENCH, socket, o/6-in.WRENCH, socket, %-in.

41

TM.9-17270~.'v.,.

1M 9-17270


23/102

11ORDNANCE MAINTENANCE - TRANSFER UNIT FOR LIGHT TANKSMS, MSA1, AND 7S-MM HOWITZER MOTOR CARRIAGE M8

I ..- ..r ..i. ..rJ w i:c 0 II0 z :5c ~iu. WUrJwZ::

\r-;: ,z w i::w z 0i WrJ Z :: ,;: w i-w ;:-i ZJ

i-;:z

42

~u~ tu to-a..i'.-oo-..::i.u'tc:tIi...I-N.::atii

11TRANSFER UNIT

(d) Remove Oil Cooler Unit.WRENCH, open-end, 1 v--in~ WRENCH, socket, lh-in.Remove clip holding fuel line to left engine fiiel pump (lh-in. socketwrench). Disconnect long oil cooler hose at elbow at rear of cooler unitand disconnect short hose at oil cooler line connection on bulkhead( i v--in. open-end wrench). Remove oil cooler unit, with short hose stilattached, through rear doors.

(3) INSTALL OIL CoOLER.(a) Install Oil Cooler Unit.WRNCH, open-end, 1 %-in. WRENCH, socket, lh-in.Raise oil cooler unit through rear doors into position over upper rearrelay cross shaft. Connect long oil ooler hose at elbow at rear of cooler

unit. Support cooler unit and install four nuts and bolts which hold rearof oil cooler to shroud (lh-in. socket wrench). Install clip holding fuelline to left engine fuel pump (lh-in. socket wrench). Work throughb~khead doors and install four nuts and bolts holding front of oil coolerunit to shroud (lh-in. socket wrench). Connect short hose to oil coolerline at bulkhead (1 v--in. open-end wrench). Install bulkhead doors.(b) Install Fan, Fan Belt, and Fart Bracket.WRENCH, socket, lo/6-in.Position fan, and fan bracket on mounting studs, and install two nutsand lock washers finger tight. CAUTION: Make sure master batteryswitch is OFF while working on fan. Slip fan belt over fan pulley and

cranbhaft pulley, and adjust fan belt tension by raising or loweringfan support until there is between %-%-inch slack when measuredby pushing inward midway between fan pulley and crankshaft pulley.Tighten two fan support mounting stud nuts (1o/6-in. socket wrench).(c) Install Fan Shrouds.WRENCH, open-end, lh-in. WRENCH, soket, o/6-in

WRNCH, socket, o/6-in. WRENCH, socket, -in.Position fan shrouds on rear of engine compartment and install screwsand lock washers (o/6-in. socket wrench). Position plate around car-buretor air inlet pipe and install three screws (o/6-in. socket wrench).Connect exhaust outlet pipes to mufers and tighten clamps (lh-in.open-end wrench). Close engine compartment doors, lubricate, and in-stall seven screws and lock washers on M5 vehicles. On M5Al vehicles,instal~ six screws leaving center screw out. Swing deflector into placeand install remaining screw.(4) REMOVE OIL COOLER HOSES.WRENCH, open-end, 1 v--in.R~move fan shrouds as explained in step (2) (a) above, and dis~connect long oil cooler hose at elbow at rear of cooler unit. Remove

43

1M 9-17270


24/102

11ORDNANCE MAINTENANCE - TRANSFER UNIT FOR LIGHT TANKSM5, M5A1, AND 75-MM HOWITZER MOTO~ CARRIAGE M8bulkhead doors and right-hand upper shell rack, disconnect long oilcooler hose from line at bulkhead, and remove hose. Disconnect shorthose at line on bulkhead and front elbow on oil cooler unt, and re-move hose.

(5) INSTALL OIL COOLER HOSES.'WRENCH, open-end, 1 'I-in.Connect short oil cooler hose to, cooler unit elbow at front of unitand to line on bulkhead. Connect long hose to line at bulkhead. Installbulkhead doors and upper right-hand shell rack. Connect long oil coolerhose to elbow at rear of cooler unit. Install ~n shrouds as explainedin step (3) (c) above.

(6) REMOVE OIL COOLER LINES.(a) Remove Turret Basket Guard (MS, and MSAl).WRENCH, socket, 6-in.Loosen screw from front of turret basket guard and lift rear of guardfrom hinges so that it can be removed.(b) Remove Rrght-hand Bulkhead Door and Extension Cover (MS,and MSAl).SCREWDRIVER WRENCH, -in.Unfasten armor plate guard latch and raise shell rack cover to catchon bulkhead. Remove screw holding shell rack guard to shell rack, andpry,guard from locating holes in extension cover. Remove three screwsand lock washers holding the 37 -mm shell rack and remove rack. Rotatebulkhead door latch so that door may be tilted forward at top and liftedoff the hinges. Remove four screws and washers holding bulkhead exten-sion cover to bulkhead extension. Pry cover upward at front end andremove.(c) Remove Right-hand Bulkhead Door and Extension Cover (M8).SCREWDRIVER WRENCH, 6-in.Remove four screws and washers holding right-hand ammunitionrack to fighting compartment walls and bulkhead, and remove ammuni-tion rack. Rotate bulkhead door latches, tilt doors forward at top andlift off hinges. Remove four screws and washers holding right-handbulkhead extension cover to bulkhead and extension. Pry cover upwardat front end and remove from vehicle.(d) Remove Right-hand Propeller Shaft Cover and Outer Housing.WRENCH, open-end, 6-in. WRENCH, socket, -in.On M8 vehicles, remove four .cap screws and lift out subfloor ( 6-in.socket wrench). On all vehicles, remove cap screws holding front and

44

1M 9-1727011

TRANSFER UNITrear covers on top of right-hand propeller shaft housing and removecovers. Remove two screws holding propeller shaft housing air baffe tosupport and remove baffe ( 6-in. socket wrench). Remove cap screwsholding outer housing and remove housing ( 6-in. open-end wrench).

(e) Remove Oil Cooler Lines.WRENCH, open-end, 6-in. WRENCH, socket, lh-in.WRNCH, open-end, 1 Va-in. WRENCH, socket, 6-inDisconnect the two setions of the oil cooler lines at the union in thecenter of the right-hand propeller shaft housing (llf-in. open-endwrench). Disconnect front lines at carrier ( 6-in. socket wrench), andremove lines. Remove clips holding transfer unit-to-oil cooler hos linesto side of inner housing and to inside of bulkhead ( 6-in. open-endwrench). Disconnect lines from hoses and remove by pullng backthroug propeller shaft housing.

(7) INSTALL OIL COOLER LINES.(a) Install Oil Cooler Lines.WRENCH, open-end, 6-in.

WRENCH, open-end, 1 Va-in.WRENCH, open-end, 1 'I-in~Position transfer unit-to-oil cooler hose lines in, the right-hand pro-

peller shaft housing and secure in place with clips mounted on innerhousing wall and on the engine side of. the bulkhead ( 6-in. open-endwrench). Connect to oil cooler hoses (ii~-in. open-end wrench). Installtrsnsfer unit-to-ciil cooler upper and lower front lines in propeller shafthousing and secure flanged ends to carrier ( 6-in. socket wrench). Re-coect the two sections of the oil cooler lines at the union in thecenter of the right-hnd propeller shaft housing (lVa-in. wrenc.h).

(b) Install Prpeller Shaft Outer Housing and Cover.WRENCH, open-end; 6-in. WRENCH, socket, 6-in.Position outer housing wall around right-hand propeller shaft andsecure with six cap screws ( 6-in. open-end wrench). Position front

cover over propeller shaft and install four mounting screws ( 6-in.soket wrench). Install two screws holding propeller shaft housing airbafe to support. PoSition rear cover over inner and outer walls andinstall five screws and lock washers holding rear cover to walls ( 6-in.socket wrench).

(c) Install Right-hand Bulkhead Door and Extension Cover (MS,and MSAl).SCREWDRIVER WRENCH, 6-in.Position bulkhead door on hinges, close door, and rtate latch tohold door closed. Place bulkhead extension cover; in place and securewith screws and lock washers. Position 37-mm shell rack and fasten in

WRENCH, socket, lh-in.WRENCH, socket, 6-in.

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1M 9-17270


25/102

-'2ORDN~NCE MAINTENANCE - TRANSFER UNIT FOR LIGHT TANKSM5, MSA1. AND 75-MM HOWITZER MOTOR CARRIAGE M8place with screws and lock washers. Insert armor plate guard aroundshell rack, making sure that button on guard engages slot in shell rack.Install screw and lock washer.

(d) Install Ri~ht-hand Bulkhead Door and Extension Covel' (M8).SCREWDRIVR WRENCH, o/6-in.Position bulkhead door on hinges, close door, and rotate latch. Placebulkhead extension cover on bulkhead and secure with four screws andlock washers. Place 7s-mm ammunition rack in p~sition and fasten in,

place with four screws and lock washers. \.e) InstaII Turret Basket Guard M5, and M5Al).

WRNCH, socket, o/6-in.Position rear of gurd on hinges on the shell rack and bulkheadextension. Install and tighten screw at front of guard.

12. REMOVAL OF TRSFER UN FROM VEIDCLE.8. When removing the transfer unit from the vehicle, it is necessryfist to remove the controlled differential and transfer unit as a complete

assmbly. The procedure for this is given in the following paragraphs.b. Equipment.

CHISELDRIFT, brassHAMMER, lightHOISTMALLETPLIERSPRYBARPUNCH, brassSIDE CUTTERSSLING, controlled differen-tial and transfer unit,Cl0s88sSLING, front deck, engineroof and gu turret,B226796SLING, transfer unit,B226795WRNCH, deep socket,

lYi6-in.46

WRENCH, open-end, %6-in.WRENCH, open-end, lh-in.WRENCH, open-end,-in. (2)WRENCH, open-end, %-in.WRENCH, open-end,lo/6-in.WRENCH, socket, %6-in.WRENCH, socket, o/6-in.WRENCH, socket, %-in.WRENCH, socket, %-in.WRENCH, socket, %-in.WRENCH, socket, lo/6-in.WRENCH, socket-head setscrew, o/6-in.WRENCH, soket-head set

SCrew, 3,1-in.

1M ,9-17270'2TRANSFER UNIT

RESISTOR, BLACKOUT DRIVING lIGHT- SWITCH, STOP LIGHT l.H.

SHAFT, TACHOMETER DRIVECABLE, HAND THROTTLECONDUIT, TO BLACKOUT RESISTORCONDUIT, TO LEFT 'HEADLAMP

.,. Ii. -..CONDUIT, STOP SWITCHESAND DOME LIGHTCONDUITS, TO CENTERJUNCTION BOX, R.H, AND l.H.CONDUIT, TO APPARATUS BOX

CONDUIT, TO VENTIATOR,CONDUIT, TO SIREN SWITCH

CONDUIT, TO RIGHT HEADLAMPRA PD 9388

Figure 22 - Connections at Rear of Instrument Pane'c. Remove Transfer Unit and Controlled Diferential.(1 ) REMOVE TRACK FROM DRI SPROCKET.DRIFT, brass PRYBARHAMER, light PUNCH, brassMALLET WRENCH, open-end, %-in.Place vehicle on level ground. Remove wedge safety nut at insideand outside of end connectors on track shoes midway between bottomof drve sprockets and ground (%-in. open-end wrench). Drive wedgesout of inside and outside track connectors with a brass punch and ahammer. Remove first the outside and then the inside end connectorson track shoes on each side of vehicle by prying with a prybar insertedbetween track links and end connectors, or by driving on end connectorswith a brass drift and a mallet, if necessary. Pull the upper portion ofeach track backward off each drive sprocket by rotating sprocket with

a prybar.(2) DRAIN OIL FROM TRNSFER' UNIT AND CONTROLLED DIFFER-. ENTIA.(See Paragraph 10 b.)

47

TM 9-17270'2,.';'.'t.~:~,.'; ,

TM 9.J 7270


26/102

ORDNANCE MAINTENANCE-TRANSFER UNIT FOR LIGHT TANKSM5, M5Al, AND 75.MM HOWITZER MOTOR CARRIAGE M8PIN, STOP LIGHT RODROD, STEERING & BRAKING CONTROL ROD, STOPLIGHTSWITCH OPERATING

LEVER, STEERING & BRAKING RElAYPIN. RElAY LEVER -PIN, RELAY LEVER LINKLINK, RElAY TO CONTROL LEVERS, RA PD 9382Figure 23 - Disconnecting, Steering, and Brake Levers

(3) REMOVE DRI SPROCKET.WRENCH, deep socket, lYi6-in.Remove eight nuts on studs holding each drive sprpcket to hub andpull sprockets from hub studs.(4) REMOVE LOWER FRONT DECK PLATE.SLING, front deck, engine roof WRENCH, socket, HYi6-in.and gun turet, B226796Remove 27 lower front deck plate mounting screws. Install slingB226796 on two lower front deck lifting handles connect a hoist to

sling, and remove lower front deck.(5) DISCONNECT SPEEDOMETER AND TACHOMETER CONDUITS AND

CABLES.PLIERSWRENCH, open-end, -in.WRNCH, open-end, 1,-in.WRNCH, soket, o/6-in.WRENCH, socket, 6-in.

48

12TRANSFER UNIT

Disconnect six electrical conduits, speedometer cable, and two tachom-eter cables from instrument panel (pliers). Disconnect opposite endof sl:edometer cable from transfer unit and remove cable. Remove twocable clip retaining screws (l/i-in. open-end wrench) and pull cablesand conduits out from under differential housing into fighting compart-ment. Remove two mounting screws and lock washers holding each ofthe two stop light switches to differential housing ( 6-in. socket wrench).Disconnect wire leads to blackout light resistor ( 3l-in. open-endwrench). Remove four screws holding resistor to controlled differentialcase (o/6-in. socket wrench) and remove resistor. Disconnect oil signalunit lead.

(6) DISCONNECT STEERING AND BRAKING LEVERS.HAMMER, light PUNCH, brassPLIERS SIDE CUTTERSRemove three cotter keys and clevis pins holding each of the twosteering and brake lever assembly links to mounting brackets on dif-ferential housing, using a pair of side cutters, a brass punch, and a lighthammer. Disconnect links from mounting brackets. Remove left andright steering and brake lever retracting springs from differential housing(pliers) .(7) REMOVE INSTRUMENT PANEL.WRENCH, open-end, 6-in.Remove two screws and lock washers holding lower left instrumentpanel mounting bracket' to fighting compartment wall. Remove twoscews and lock washers holding l,pper right instrument panel mount-

ing bracket and hand throttle cable bracket to upper front deck andswing instrument panel backward next to fighting compartment wall.Lower hand throttle cable and bracket down on differential housing.(8) REMOVE SIREN SWITCH AND CABLE.WRENCH, socket, 1,-in.Remove two screws holding siren switch to floor, and pull siren switchand cable out from under differential housing.(9) REMOVE HAND THROTTLE CABLE.PLIERS WRENCH, open-end, -in. (2)Remove hand throttle cable nut next to web on bottom of differential

housing while holding hexagonal flange on cable (two -in. open-endwrenches). Disconnect hand throttle cable trunnion at accelerator pedalrelay and remove throtte cable by pullng it forward through web onbottom of differential housing (pliers).

49

1M 9-1727D n\~:~.;;';.~.:~

1M 9-17270'2


27/102

'2ORDNANCE MAINTENANCE-TRANSFER UNIT FOR LlGHT TANKSM5, M5A1, AND 75-MM HOWITZER MOTOR CARRIAGE M8

(10) DISCONNECT TRNSFER UNIT THROTTLE VALVE LINKAGE.SIDE CUTTERSDisconnect transfer unit throttle valve linkage at relay on rear end

of tranfer unt by :emoving cotter key.(11) DISCONNECT TRA~MI,SSION AND TRNSFER UNIT MANUALCoNTROL ROD. ~SIDE CUTTERSDisconnect transmission and transfer unit manual control rod fromselecor lever to intermediate relay at selector lever, using a pair ofside cutters to remove cotter key (fig. 18).(12) DISCONNECT UNIVERSAL JOINT AT TRANSFER UNIT.CHISEL' WRENCH, open-end, lh-in.HAMMER, light WRENCH, socket, o/6-in.Remove seven screws and lock washers holding left and right frontuniversal joint covers on propeller shaft housings, and remov covers(o/6-in. socket wrench). NOTE: On M8 Vehicles, it is necessary toremove subfloor first. Bend back universal joint locking plates, usinga chisel and a light hammer, and remove two screws that hold each

unversl joint bearing cap to yokes on rear of transfer unit (lh-in.,opn-end wrench). Slide propeller shafts t,oward rear of vehicle, com-pressing sliding joint.

, (13) DISCONNECT OIL COOLER PIPES AND BRACKETS.WRNCH, socket, o/6~in.Remove four screws and lock washers holding oil cooler pipe mount-

ingbrackets to transfer unit case, and disconnect oil cooler pipes andbrackets from transfer unit.(14) RKMOVE FILLER BLOCKS AND SHIMS.WRENCH, socket, Va-in.Remove two cap scre~s and lock washers holding each filler blockto each end of differential housing, and remove both filler blocks andfiler block shims.

TRANSFER UNIT

Sling Tool No.C-105885

ControlledDifferential

Mount'Sling Hookson Upperand Lower

Housing Ribs

Transfer Unit

RA PD 8639

Figure 24 _ Installation of Transfer Unit and ControlledDifferentia Sling

pins prvided (fig. 24). Connect a hoist on sling and draw up cableuntil it is taut.(16) REMOVE TRANSFER UNIT AND CONTROLLED DIFFERENTIAL.WRENCH, pen-end, -in. WRENCH, socket, lo/16-in.WRNCH, soket, -in.

5'

IITI I-I/I.ILI ~ ..12ORDNANCE MAINTENANE-TRANSFER UNIT FOR LIGHT TANKS

'2TRANSFER UNIT


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M5,M5A1, AND 75.MM HOWITZER MOTOR CARRIAGE M8

RA PD 8497Figure 25 - Removing Transfer Unit and Controlled Differentia'

IM5 Shown'Remove 21 screws holding nose armor casting to hull floor (lo/6-in.socket wrench)~ Remove 11 bolts that hold, each end of differential

housing to hulI, using a %-inch open-end wrench on nut inside fightingcompartment, and a %-inch socket wrench on boIthead outside ofvehicle. Tighten hoist cable until it is bearing weight of nose armorcasting, final drives, controlled differential, and transfer unit assembly'pull assembly forward and remov'e from vehicle (fig. 25). NOTE: Re~move differ~ntial housing~to-hulI shims as assembly clears hull. Keep~eft-hand shims separate from right-hand shims so that they may beinstalIed on the same side as removed, if controlled differential andtransfer unit are to be installed in same vehicle.

52

l....ol'e'

BOLTS, TRANSFER UNITTO DIFFERENTIAL ,~

WRENCHES, lBRA PD 9296

Figure 26 - Removing lower Transfer Unit Bo'tsd. Removal of Transfer Unit from Controlled DifferentiaL.(1) REMOVE LOWER BOLTS.WRENCH, socket, -in. (2)While unit is stil suspended on special sling, remove the four lower

bolts and nuts that hold the transfer unit to the differential housing(fig. 26).(2) REMOVE DIFFERENTIAL SLING.Lower differential and transfer unit assembly at place where dif-ferential wil remain. Remove cotter pin from upper clamp on sling,take out clamp, and remove sling from differential housing.(3) INSTALL TRANSFER UNIT SLING.SLING, transfer unit WRENCH, open-end, %-in.B226795Install sling on transfer unit by turning' sling bolts into holes intransfer unit (fig. 27) using an open-end wrench. Attach hook of hoist tosling and take up weight of transfer unit.

53

1M 9-17270'2-'3 TM 9-1727013 '


29/102

ORDNANCE MAINTENANCE-TRANSFER UNIT FOR LIGHT TANKSM5, M5A1, AND 75-MM HOWITZER MOTOR CARRIAGE M8

SLING, TOOL NO. B-226795

RA PD 9297Figure 27 -Installng Transfer Unit SIi g

(4) REMOVE TRNSFER UNIT.WRENCH, open-end, lo/6-in. WRENCH, ;socket, 'l-in.With hoist just beginning to take the weight or the transfer unt,remove 11 cap screws ('l-in. socket wrench) and five ,ntits; gt lockwashers (io/6-in. open-end wrench) that hold transtt unit to dU-ferential housng. Install two %6-14 screws in holes in transfer unitcase, shown in figue 28, and tighten screws to push transfer unit awayfrom differential and off dowels. Lower transfer unt to bench andremove hoist and sling.13. DISASSEMBLY OF TRSFER UNIT.a. Equipment.ARBOR, needle bearing

loading, A.266519BLOCK, 3-in. (2)CHISELDRIFT, brass

DRIVER, idler gear bearing,A266s14HAMMER, lightHAMMER, soft

54

HOlSTHOOK, clutch and drum as-,sembly, lifting, A266513PLIERS,PLIERS, snap ring, remov-ing, A266329PRYBAR, small (2)PtnLER, gea~ B226841PtnLER, idler gear shaft,A266s18PtnLER, mainshaft bearing, ,A26ss15PtnLER, pinion gear, trans-fer case, CL05886SCREW, 1;-20 threadSCREW, 6-14, 2 ll in.

long (2)SCREWDRIVER (2)SIDE CUTTERSWRENCH, ll-in.WRNCH, 1i6-in.WRENCH, -in.WRENCH, 1l/-in.WRENCH, box, 1i6-in.

TRANSFER UNITWRENCH, deep socket,

o/ 6-in.WRENCH, deep soketi 1;-in.WRENCH, open-end, 6-inWRENCH, open-end, 1f-iWRENCH, open-ed, o/6-iWRENCH, open-ed,lo/6-in.WRENCH, open-end,

1 ll-in.WRENCH, open-end,llo/6-in.WRENCH, socket, 6-in.WRENCH, socket, 2-in.WRENCH, socket, o/6-inWRENCH, socket, 5/s-inWRENCH, socket, -in.WRENCH, socket, 1l/-inWRENCH, socket, 1 JA-inWRENCH, socket, llo/16-inWRENCH, socket, 2-inWRENCH, spanner,A1619s4b. Disassembly of Case.(1) REMOVE CoNTROLLED DIFFERENTIAL BRAKE BAND LUBRICATrOR'TuBE. WRENCH, ll-in.Remove screw and lock washer holding controlled differential brae

band lubrication tube asssembly from front face of transfer unt, andremove lubrication tube assembly (fig. 29).(2) REMOVE OUTPUT SHAFT BEARING RETAINER.SIDE CUTTERS WRENCH, open-end, lo/6-inRemove two lock wires for output shaft bearing retainer mountinuts (fig. 30), and remove four mounting nuts. Pull bearing retainerfrom transfer unit case (fig. 31).(3) REMOVE PINION AND BEARING.PtnLER, pinion, gear, WRENCH, open-end,transfer case, Cl0s88611o/6-in.SIDE CUTTERS WRENCH, socket, 2-in.Straighten cotter pin in pinion retaining nut (fig. 31), and drive pinout of nut and shaft. Remove pinion retaining nut, using a 2-inch socket

55

TM 9-17270'3 . oi~:: :':,;, ',.

1M 9-1727013


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ORDNANCE MAINTENANCE-TRANSFER UNIT FOR LIGHT TANKSM5, M5A1, AND 75-MM HOWITZER MOTOR CARRIAGE M8..LING, TOOL NO. B-226795

~~-__.~_~r/(RA PD 9298

Figure 28 - Removing Transfer UnitTUBE, ASSEMBLY STEERING BRAKE lUBRICATION

~l':i ;:',.: 'f ,.,

RA PD 9300Figure 29 - Removing Lubrication Tube

56

TRANSFER UNITSIDE CUTTERS

'1:

:::

_ Figure 30 - Removing I.ock Wires for Bearing Reta;ner Nutswrench, while keeping the transfer unit shafts from turning by holdingone of the universal joint yokes with a 11%6-inch open-end wrench, asshown in figure 32. Take retaining nut and thrust washer from shaft.Attach special puller to pinion as shown in figure 33, and pull pinionand bearing from shaft. Remove puller from pinion.

4) REMOVE BEARING FROM PINION.DRIFT, brassBLOCK, 3.:in.HAMMER, light

i

WRENCH, open-end,11%6-in.WRENCH, spanner,A161954

Place pinion and bearing assembly on bench, and bend back tang onspanner nut lock plate, using a drift and hammer (fig. 34). Insertpinion and bearing assembly on output shaft with pinion toward case(fig. 35). Assembly is mounted in this position so that pinion can bekept from turning by holding one of the universal joint yokes as shownin figure 32. Remove spanner nut by using special spanner wrench. Takeassembly from output shaft and bump pinion against a block of wood

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8/12/2019 TM 9-1727D Transfer Unit for Light Tanks M5, M5A1 and 75-Mm Howitzer Moto

TM 9-1727D Transfer Unit for Light Tanks M5, M5A1 and 75-Mm Howitzer Motor Carriage M8 1943

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Transcript of TM 9-1727D Transfer Unit for Light Tanks M5, M5A1 and 75-Mm Howitzer Motor Carriage M8 1943