After a prolonged period of life, it is normal that the bearing shows some particles of dirt embedded in the babbit and has small cracks, which should not be be severe.
Bearings also suffer form wear and tear as happens with all the active parts of an engine.
This is due to the normal wear that occurs after a certain milage, depending on the conditions in which the engine has been operated in. Temperatures, loads, and extreme speed cause the acceleration of the bearing's normal wear. Some of the causes of premature bearing failure are fatigue, dirt embedment, dealignment, oil starvation, cavitation, distorted crankcase, and distorted crankshaft. Here are some illustrations of these types of engine bearing damage. We have included recommendations to help prevent premature bearing failures, both during the rebuilding process, and after the engine has been placed into service. .