In most cases when the engine is overhauled one is required to remove the main & connecting rod bearings then replace them with fresh ones while the removed bearings act as a bench reference on the status of the engine. Failure of bearings mainly results from lack of lubrication, presence of dirt or other particles, overloading of engine, and rusting hence corrections must be done before assembly to avoid the same. While inspecting the bearings they should be withdrawn from the particular place or area and arranged on the clean surface so that they can be match-marked or compared to the crankshaft journal. Contaminants can be brought into the engine during assembly, thru filters, or from machining operations and become lodged in the bearing material and cause scoring or gouging. To avoid this, all parts should be cleansed properly, and the oil and filter changed as often as should be. Lubrication can fail by burn-off, over; loading, leakage of oil, or plugging of the oil passages, and consequent severe damage may include the bearing material being extruded from its backing. There are also driving habits, which have considerable effect on bearings; for example, luging the engine will cause high loads and short trip causes corrosion. Further, improper bearing installation also shorten the life of the bearing as they can cause proper oil starved or, high spots that leads to failure.