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.
NOTE: Do not disassemble an engine for repair based solely on the results of an oil analysis. Inspect the oil
filters. If an oil filter shows evidence of internal engine damage, find the source of the problem and repair the
damage. Reference the appropriate procedure(s) based on the following oil filter inspection.
Restrain the full flow lubricating oil filter and use care when cutting open the upper section of the
combination filter. The filter element spring is under compression and can cause personal injury.
Use tube cutter, Part Number 3376579, to open the upper section of the bypass full-flow oil filter.
Inspect the filter element for evidence of moisture or metal particles.
