Crankshaft Bearing Inspection

WARNING: This page is about a different variant/trim than selected.

NOTE: All connecting rod and main journal bearings that have been used in a running engine must be replaced. Never re-use the crankshaft or connecting rod bearings.

The following bearing wear conditions should be used to diagnose engine operating conditions or root cause of a condition.

Fig 1: Bearing Craters Or Pockets

Courtesy of GENERAL MOTORS CORP.

Inspect for fatigue indicated by craters or pockets. Flattened sections on the bearing halves also indicate fatigue.

Fig 2: Bearing Scoring Or Discoloration

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Inspect for excessive scoring or discoloration on both front and back of the bearing halves.
Inspect the main bearings for dirt imbedded into the bearing material.

Fig 3: Improper Seating

Courtesy of GENERAL MOTORS CORP.

Inspect for improper seating indicated by bright, polished sections.