BOLT-LOCKING 5P6851 - Caterpillar

Probable Causes
Dirt in the engine oil
Air inlet leaks
Fuel leakage into engine oil
Incorrect engine oil
Incorrect maintenance interval for the application
Incorrect engine settingsRecommended Repairs
Dirt in the Engine Oil
Remove dirty engine oil. Install new filter elements. Put clean oil in the engine. Check the oil filter bypass valve for a weak spring or a broken spring. Look for the source of the contamination.Air Inlet Leaks
Inspect the air filter for leaks. Inspect all gaskets and connections. Make repairs if leaks are found.Fuel Leakage into the Engine Oil
Fuel leakage into the engine oil will cause high fuel consumption and low engine oil pressure. This condition may also increase the oil level in the crankcase. Make repairs if leaks are found. Install new parts, as required.Incorrect Engine Oil
Check oil recommendations for the proper oil specifications for the engine operating conditions.Incorrect Maintenance Interval
Review the oil change intervals in relation to the nature and severity of the engine application. Review the records for the engine in order to verify that the recommended intervals are being followed.Incorrect Engine Settings
Check the following items for proper adjustment:
Timing
Unit injector synchronization
Fuel setting
Valve lashRefer to System Operation, Testing and Adjusting for more information.