Info Centre >> Fuel and Lube Oil Technical Manual >> 7. Lube Oil - Test Results >> 7.9 Directory of Bearing Failures >> Fretting
ALWAYS tighten bearing caps to the correct settings, use a well-maintained torque wrench/hydraulics and lubricate threads according to the instruction manual.
1 - fretting damage to the edge of a bearing shell
2 - static fretting due to machinery exposed to external vibrations
3 - fretting on the rear of a shell bearing. This is common but generally not threatening.
4 - fretting again, this time it is severe in way of the joint edge and cannot be allowed to continue. Probably damage has also occurred to the bearing housing.
5 - fretting at two localised spots has resulted in high spots on the bearing face itself. Could eventually result in localised wiping, hopefully this would be self healing.