Engine Block: Crankshaft: Inspection
- Clean the oil off the bearing journals.
- Use a micrometer (1) to correctly measure the outside diameter of the main bearing journals (2).
- Measure the outside diameter at two locations (each end of the journal).
- Rotate the crankshaft 90° and repeat the two measurements.
- For main bearing journals, verify that the maximum taper and maximum out of round are within specifications. Refer to ENGINE SPECIFICATIONS .
- Compare the measured main bearing journal diameter to the crankshaft main bearing journal diameter grade marking chart. Refer to
BEARING(S), CRANKSHAFT, MAIN, STANDARD PROCEDURE . Obtain the main bearing journal grade identification marks from the engine block and select the upper and lower main bearing sizes that will provide the proper oil clearance.
- Use a micrometer (1) to correctly measure the outside diameter of the connecting rod journals (2).
- Measure the outside diameter at two locations (each end of the journal).
- Rotate the crankshaft 90° and repeat the two measurements.
- For connecting rod journals, verify that the maximum taper and maximum out of round are within specifications. Refer to ENGINE SPECIFICATIONS .
- Compare the measured rod journal diameter to the crankshaft connecting rod bearing journal diameter grade marking chart. Refer to BEARING(S), CONNECTING ROD, STANDARD PROCEDURE . Select the bearing size that corresponds to the crankshaft markings for each rod bearing journal that will provide the proper oil clearance.