Cummins N14 STC, Celect, Celect Plus – Service Manual Lubricating Oil Sludge in the Crankcase Excessive

Bulk oil supply is contaminated

Check the bulk oil supply. Drain the oil and replace with non-contaminated oil. Change the oil filters. Refer to Procedure 007-037 and Procedure 007-013 in Section 7.

Lubricating oil does not meet specifications for operating conditions

Change the oil and filters. Refer to Procedure 007-013 in Section 7.

Lubricating oil drain interval is excessive

Verify the correct lubricating oil drain interval. Refer to Procedure 102-002 in Section 2 of the N14 Plus Operation and Maintenance Manual, Bulletin 3666136.

Fuel grade is not correct for the application or the fuel quality is poor

Operate the engine from a tank of known high quality fuel. Refer to Fuels for Cummins® Engines, Bulletin 3379001.

Coolant temperature is below specification

Refer to the Coolant Temperature Below Normal troubleshooting symptom tree in Section TS.

Lubricating oil is contaminated with coolant or fuel

Refer to the Lubricating Oil Contaminated troubleshooting symptom tree in Section TS.

Crankcase pressure is excessive

Check for excessive blowby. Refer to the Crankcase Gases (Blowby) Excessive troubleshooting symptom tree in Section TS.

Crankcase ventilation system is plugged

Check and clean the crankcase breather and vent tube. Refer to Procedure 003-001 in Section 3.

STC system malfunction

Check the electrical STC oil control valve and circuit. Refer to Procedure 006-037 in Section 6.

Injector cup is damaged or is not correct

Check the injector cups for damage and for correct part numbers. Refer to Procedure 006-026 in Section 6.

Static injection timing is not correct

Check the static injection timing. Refer to Procedure 006-025 in Section 6.