Measuring Crankshaft Bearing Clearances - Micrometer Method
- Measure the crankshaft journal diameter with a micrometer in several places, approximately 90 degrees apart. Average the measurements.
- Determine the taper and out-of-round of the journal. Refer to Engine Mechanical Specifications .
- Install the bearings into the engine block or connecting rod assembly.
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- Install the bearing cap bolts and tighten to specifications. Refer to Fastener Tightening Specifications .
- Measure the bearing inside diameter (ID) at two points 90 degrees apart. Average the measurements.
- In order to determine the bearing clearance, subtract the average journal diameter from the average bearing inside diameter.
- Compare the readings to specifications. Refer to Engine Mechanical Specifications .
- Replace bearing halves as required to obtain the proper bearing clearances.
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