Cummins ISX11.9 CM2250 – Service Manual Air Compressor Pumping Excess Lubricating Oil into the Air System

Lubricating oil drain interval is excessive

Verify the correct lubricating oil drain interval. Refer to Procedure 102-002 in Section 2 of the Operation and Maintenance Manual, ISX11.9 CM2250, Bulletin 2883444.

Air intake system restriction to air compressor is excessive

Replace the air compressor air cleaner (if installed). Check the air intake piping. Check the engine air intake restriction if the air compressor inlet is plumbed to the vehicle or equipment intake system. Refer to
Procedure 010-031 in Section 10
.

Air compressor pumping time is excessive

Check the air compressor duty cycle. Install a larger air compressor, if available. Check for and repair all air system leaks. Refer to the OEM service manual.

Carbon buildup is excessive in the air discharge line, check valve, or cylinder head

Check for carbon buildup. Replace the air compressor discharge line, if necessary. Refer to Procedure 012-003 in Section 12 and
Procedure 010-033 in Section 10.

Engine angularity during operation exceeds specification

Refer to the Engine Specification data sheet.

Crankcase pressure is excessive

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

Air compressor runs hot

If coolant temperature is above normal, refer to the Crankcase Gases (Blowby) Excessive symptom tree.

Air compressor is excessively worn or internally damaged

Replace the air compressor. Replace the desiccant element on the air dryer, if equipped. Refer to Procedure 012-014 in Section 12 and the OEM service manual.