In this work a comprehensive review of the basic lubrication mechanisms that would exist in engine lubrication will be discussed. The subsequent effect of lubricants (new or used) on engine wear is also, herein, summarized and followed by a description of test procedure on a specially constructed test machine to analyse wear under dry or lubricated contacts. Results have also been presented to compare the effect of change in oil properties and the presence of contaminants after prolonged time of use on the wear rate. A detailed theoretical study is also given to dynamic performance. The dimensional changes in applying hydrodynamic lubrication theories frictional resistance, oil flow rate and side be fully computed and analysed. assess the effect of engine wear on the hydro-in crank bearings due to wear have been considered and their effect on the load carrying capacity, leakage and maximum hydrodynamic pressure could