TM 9-2320-272-24-4
5-27. CAMSHAFT AND GEAR MAINTENANCE
THIS TASK COVERS:
d. Cleaning and Inspection
a. Check Backlash and End Play
e. Assembly
b. Removal
f. Installation
c. Disassembly
INITIAL SETUP:
MATERIALS/PARTS
APPLICABLE MODELS
Dowel pin (Appendix D, Item 98)
M939A2
Lockwasher (Appendix D, Item 396)
SPECIAL TOOLS
GAA grease (Appendix C, Item 28)
Adhesive sealant (Appendix C, Item 4)
Cam bushing replacement tool
Rags (Appendix C, Item 58)
Drycleaning solvent (Appendix C, Item 71)
TOOLS
REFERENCES (TM)
General mechanic's tool kit (Appendix E, Item 1)
TM 9-2320-272-24P
Gear puller (Appendix E, Item 102)
Dial indicator (Appendix E, Item 36)
EQUIPMENT CONDITION
Inside micrometer (Appendix E, Item 82)
Engine mounted on repair stand (para. 4-9).
Outside micrometer (Appendix E, Item 80)
Rocker levers and push rods removed (para. 4-41).
Vernier caliper (Appendix E, Item 159)
Flywheel housing removed (para. 4-43).
Torque wrench (Appendix E, Item 144)
Oil pan and suction tube removed (para. 4-47).
Arbor press
Front gearcase cover removed (para. 4-48).
Prybar
GENERAL SAFETY INSTRUCTIONS
Keep fire extinguisher nearby when using
drycleaning solvent.
Drycleaning solvent is flammable and toxic. Do
not use near open flame.
a. Check Backlash and End Play
1.
Rotate engine block (2) so bottom is facing upward.
2.
Install dial indicator on engine block (2) and crankshaft gear (1).
NOTE
Prevent crankshaft from rotating when checking backlash.
Reading will be the total of both gears.
3.
Rotate camshaft gear (3) clockwise until teeth contact teeth of crankshaft gear (1).
4.
Set dial indicator to zero.
5.
Rotate camshaft gear (3) counterclockwise until teeth contact crankshaft gear (1) teeth. Ensure
crankshaft gear (1) does not turn.
6.
Backlash of camshaft gear (3) should read 0.005-0.013 in. (0.13-0.33 mm). If reading is not within
limits, replace camshaft (tasks b through f.).
7.
Position dial indicator on face of camshaft gear (3). Press camshaft gear (3) towards rear of engine
block (1).
8.
Set dial indicator to zero.
9.
Pull camshaft gear (3) to front of engine block (1).
10.
End play of camshaft gear (3) should read 0.006-0.010 in. (0.152-0.254 mm). If reading is not within
limits, replace camshaft support (tasks b through f).
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