ISC, ISCe, QSC8.3, ISL, ISLe3, ISLe4 and QSL9 Engines – Coolant in the Lubricating Oil

Symptom Tree  t025

This is symptom tree t025
Cause Correction

Lubricating oil cooler is malfunctioning

Check the oil cooler. Refer to Procedure 007-003.


Air compressor cylinder head is cracked or porous, or has a leaking gasket

Inspect the air compressor cylinder head and gasket. Refer to Procedure 012-014.


Cylinder head core and expansion plugs leaking or misassembled

Check cylinder head. Refer to Procedure 002-004.


Cylinder head gasket is leaking

Check the cylinder head gasket. Refer to Procedure 002-021.


Cylinder head is cracked or porous

Pressure-test the cylinder head. Refer to Procedure 002-004.


Cylinder block is cracked or porous

Remove the oil pan. Pressure-test the cooling system to check for leaks. Refer to Procedure 008-020.

Last Modified:  29-Jul-2005