6. Crankshaft and Crankshaft Bearing
6. CRANKSHAFT AND CRANKSHAFT BEARING1) Clean crankshaft completely and check for cracks by means of red lead check etc., and replace if defective.
2) Measure the crankshaft bend, and correct or replace if it exceeds the limit.
CAUTION: If a suitable V-block is not available, install #1 and #5 crankshaft bearing on cylinder block, position crankshaft on these bearings and measure crankshaft bend using a dial gauge.
Crankshaft bend limit:
0.035 mm (0.0014 in)
3) Inspect the crank journal and crank pin for wear. If not to specifications, replace bearing with an undersize one, and replace or recondition crankshaft as necessary. When grinding crank journal or crank pin, finish them to the specified dimensions according to the undersize bearing to be used.
Crank pin and crank journal:
Out-of-roundness
0.020 mm (0.0008 in) or less
Taper limit
0.07 mm (0.0028 in)
Grinding limit
0.25 mm (0.0098 in)
4) Measure the thrust clearance of crankshaft at center bearing. If the clearance exceeds the limit, replace bearing.
Crankshaft thrust clearance:
Standard
0.030 - 0.115 mm (0.0012 - 0.0045 in)
Limit
0.25 mm (0.0098 in)
5) Inspect individual crankshaft bearings for signs of flaking, seizure, melting, and wear.
6) Measure the oil clearance on each crankshaft bearing by means of plastigauge. If the measurement is not within the specification, replace defective bearing with an undersize one, and replace or recondition crankshaft as necessary.