TM 5-4310-451-14
5-32. MAIN BEARINGS AND CRANKSHAFT MAINTENANCE (Con’t).
c. CLEANING AND INSPECTION I
WARNING
Dry cleaning solvent, P-D-680, is toxic and flammable. Always wear protective goggles and
gloves, and use only In a well-ventilated area. Avoid contact with skin, eyes, and clothes, and DO
NOT breathe vapors. DO NOT use near open flame or excessive heat. The solvent’s flash point Is
1000F-1380F (38OC-59°C). If you become dizzy while using cleaning solvent, Immediately get
fresh air and medical help. If solvent contacts eyes, Immediately wash your eyes and get medical
aid.
1.
Clean crankshaft and bearing caps with dry cleaning solvent and rag.
2.
Flush oil passages in crankshaft.
3.
Inspect crankshaft for scoring and overheating.
4.
Inspect crankshaft and journals for deep scratches and cracks. Replace crankshaft if damaged.
5.
Inspect crankshaft keyway for damage and cracks.
6.
Inspect rear oil seal contact surface for deep scratches. If scratches cannot be smoothed out with abrasive cloth,
replace crankshaft.
7.
Inspect timing gear for chipped teeth.
8.
Measure and note thickness of thrust washers. Measurement must be 0.1205-0.1220 in. (3.0607-3.0988 mm).
9.
Check measurement of main bearing journals. Measurement must be 4.499-4.500 in. (11.427-11.430 cm).
10.
Check measurement of connecting rod journals. Measurement must be 2.999-3.000 in. (7.617-7.620 cm).
11.
Check that maximum out-of-round for all journals does not exceed 0.0015 in. (0.0381 mm).
12.
Check that minimum taper of all journals is 0.0010 in. (0.0254 mm).
13.
Measure Inside diameter of main bearings (vertical axis). Measurement must read 4.5016-4.5040 in. (11. -
11.4402 cm).
14.
Measure bearing thickness 900 from parting line. Minimum allowable measurement is 0. 1540 in. (3.9116 mm).
15.
Measure bearing-to-journal clearance. Maximum allowable measurement is 0.0060 in. (0.1524 mm).
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