An analysis of used oil can help diagnose internal engine damage and determine if it was caused by one of the following:

• Intake air filter malfunction.
• Coolant leaks.
• Oil diluted with fuel.
• Metal particles causing wear.

For additional oil analysis information, refer to Cummins® Engine Oil and Oil Analysis Recommendations, Bulletin 3810340.

Do not disassemble an engine for repair based only on the results of an oil analysis. The oil filter must also be inspected. If the oil filter shows evidence of internal damage, find the source of the problem and repair the damage. Refer to the appropriate procedure(s) based on the following oil filter inspection.

CAUTION  Carefully cut open the upper section of the combination filter. The filter element spring is under compression and can cause personal injury.

Use the tube cutter, Part Number 3376579 or equivalent, to open the upper section of the combination filter.

Inspect the filter element for evidence of moisture or metal particles.