Jeep 2421305 Rod Bearing

On an engine overhaul it is appropriate for the main and connecting rod bearings to be replaced by new ones but the old bearings must be retained as they can greatly indicate the state of the engine. The main causes of bearing failure include the following and should be corrected before the next assembly: Lack of adequate lubrication, the presence of dirt or counter parts, overloading of the engine, and corrosion. During the inspection of bearings they are to be taken out from the components of the engine and arranged in positions in which they were originally fit on a clean surface to match the failure with the corresponding crankshaft journal. Foreign particles can for instance contaminate the assembly equipment or filters, or be intruding through machining residues, and penetrate into the bearing during its manufacture, or during assembly, or during use at a later time; particles of this size are imbedded in the soft bearing material, and larger ones produce scoring or gouging. To avoid such a failure, the cleaning of all assemblies and constant replacement of oil and filters is required. This is through a process of overheating, overloading, oil leakage or blocked oil ways and results in a case of bearing material being rubbed off fully from its backing. It is also noteworthy that driving behaviour affects bearing life; for example, full power at low speed results in high loads that extrude oil film and cool start-and-stop cycles may promote corrosion. Further, mismounting of bearings leads to the problem of oil starvation, or high spots which leads to failure.