Types of wear of main and connecting rod bearings
A. Scratches due to dirt ingress; B. Insufficient lubrication, localized abrasion; C. Incorrect installation of bearings; F. Fatigue wear; D. Tapering of the journals, wiping of the bearing coating from the entire surface along the length of the bearing; E. Formation of a flange on the edge of the bearing
1. Used bearings should be stored at their installation location for careful inspection, as wear marks on these parts can help restore the overall condition of the engine. Bearing liners are divided into size groups by thickness, indicated by color marking.
2. Causes of crankshaft bearing failure include insufficient lubrication, dirt and foreign particles, engine overload, and corrosion. Regardless of the cause of bearing failure, it should be corrected before final engine assembly.
3. Remove the bearings from the cylinder block and lay the liners out on a clean surface in the order they were installed.
4. To prevent accelerated wear due to contamination, maintain cleanliness when assembling the engine. During operation, it is recommended to change the oil and filters more often.
5. If there is insufficient lubrication, the bearing coating material is wiped off the steel base, and the bearing crumbles from overheating (a bluish tint is observed).
6. When driving in difficult engine conditions (with the throttle fully open, or at low speed in a higher gear) the bearing coating is torn off from the steel base in the form of small particles, and the bearings are subject to fatigue wear.
7. Frequent short-distance travel can cause corrosive wear of bearings, as insufficient heating does not allow condensed moisture to be removed.
8. Incorrect installation of bearings during assembly also leads to their premature wear. If the clearance in the bearings is less than the norm, then their lubrication is difficult, which leads to wear as well as due to "oil starvation".
9. When assembling, do not touch the surfaces of the liner with your fingers.
10. Main and connecting rod bearing shells must be replaced during major repairs.