Crankshaft: Testing and Inspection
InspectionCrankshaft And Crankshaft Bearing
1. Clean the crankshaft completely, and check it for cracks using liquid penetrant tester. Replace if faulty.
2. Measure the bend of crankshaft. If it exceeds the limit, repair or replace it.
NOTE: If a suitable V-block is not available, install #1 and #5 crankshaft bearing on cylinder block, position the crankshaft on these bearings, and then measure the crankshaft bend using a dial gauge.
Crankshaft bend limit: 0.035 mm (0.0014 inch)
3. Inspect the crank journal and crank pin for wear. If they are not within the specifications, replace the bearing with a suitable (undersize) one, and replace or recondition crankshaft as necessary. When grinding the crank journal or crank pin, finish them to the specified dimensions according to the undersize bearing to be used.
Crank pin:
Out-of-roundness 0.003 mm (0.0001 inch)
Cylindricality 0.004 mm (0.0002 inch)
Grinding limit To 51.750 mm (2.0374 inch) dia.
Crank journal:
Out-of-roundness 0.005 mm (0.0002 inch)
Cylindricality 0.006 mm (0.0002 inch)
Grinding limit To 59.750 mm (2.3524 inch) dia.
4. Measure the side clearance of crankshaft at center bearing. If clearance exceeds the limit, replace the bearing.
Crankshaft side clearance:
Standard 0.030 - 0.115 mm (0.0012 - 0.0045 inch)
Limit 0.25 mm (0.0098 inch)
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 the defective bearing with an undersize one, and replace or recondition the crankshaft as necessary.
Crankshaft oil clearance:
Standard 0.010 - 0.030 mm (0.0004 - 0.0012 inch)
Limit 0.040 mm (0.0016 inch)