STUD (7 15/16" LONG) 1B2571 - Caterpillar

Scheduling a Major Overhaul
Generally, a major overhaul is performed for every fifth top end overhaul. The need for a major overhaul is determined by several factors. Some of those factors are the same factors that determine the in-frame overhaul:
An increase of oil consumption
An increase of crankcase blowby
A decrease and variation of cylinder compressionOther factors must also be considered for determining a major overhaul:
Power output
The service hours of the engine
Reduced oil pressure
The wear metal analysis of the lube oil
An increase in the levels of noise and vibrationAn increase of wear metals in the lube oil indicates that the bearings and the surfaces that wear may need to be serviced. An increase in the levels of noise and vibration indicates that rotating parts require service.Note: It is possible for oil analysis to indicate a decrease of wear metals in the lube oil. The cylinder liners may be worn so that polishing of the bore occurs. Also, the increased use of lube oil will dilute the wear metals.Monitor the engine as the engine accumulates service hours. Consult