TM 9-2320-272-24-2
4-14. CRANKSHAFT VIBRATION AND DAMPER REPLACEMENT
THIS TASK COVERS:
c. Inspection
a. Runout and Wobble Check
d. Installation
b. Removal
INITIAL SETUP:
REFERENCES (TM)
APPLICABLE MODELS
TM 9-2320-272-24P
M939/A1
EQUIPMENT CONDITION
SPECIAL TOOLS
l Radiator fan shroud removed (para. 3-63).
Barring tool (Appendix E, Item 8)
Radiator fan blade removed (para. 3-72).
TOOLS
l Alternator belts removed (para. 3-78).
General mechanic's tool kit (Appendix E, Item 1)
Dial indicator (Appendix E, Item 36)
MATERIALS/PARTS
Six lockwashers (Appendix D. Item 350)
a. Runout and Wobble Check
NOTE
Perform steps 1 through 3 to check for runout.
1.
Mount dial indicator and holding fixture on front gearcase cover (2).
2.
Position dial arm on vibration damper (1) at surface (3) and zero-dial indicator.
3.
Using barring tool, rotate vibration damper (1) and take reading. If reading exceeds 0.025 in.
(0.63 mm), replace vibration damper (1).
NOTE
l Perform steps 4 through 6 to check for runout.
l Crankshaft must be kept at front or rear limit of thrust while
checking vibration damper for wobble.
4.
Using mounted dial indicator, position dial arm on vibration damper (1) at surface (4) and zero-dial
indicator.
5.
Using barring tool, rotate vibration damper (1) and take reading. If reading exceeds 0.030 in.
(0.76 mm), replace vibration damper (1).
6.
Remove dial indicator and fixture.
Remove six screws (5), lockwashers (6), and vibration damper (1) from crankshaft flange (7). Discard
lockwashers (6).
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