Probable Causes
Cooling System
- Leaks in the cooling system
Engine Oil Cooler
- Leaks in the core of oil cooler
Cylinder Head Gasket
- Leaks in the cylinder head gasket
- Damaged water seals
Cylinder Head
- Cracks in the cylinder head
Cylinder Liner
- Cracks in a cylinder liner
Cylinder Block
- Cracks in the cylinder block
Recommended Actions
Leaks in the Cooling System
Pressurize the cooling system. Refer to Systems Operation/Testing and Adjusting, “Cooling System – Test”. If the test indicates a drop in pressure and no outside leaks are detected in the cooling system, there may be an internal leak. Make any repairs, as required.
Leaks in Core of Oil Cooler
Check for leaks in the oil cooler core.
Leaks in the Cylinder Head Gasket
Inspect the cylinder head gasket for leaks.
Damaged Water Seals
Inspect the water seal for damage.
Cracks in the Cylinder Head
Check for cracks in the cylinder head. If a crack is found, repair the cylinder head and/or replace the cylinder head.
Cracks in a Cylinder Liner
Check for cracked cylinder liners. Replace any cracked cylinder liners.
Cracks in the Cylinder Block
Inspect the cylinder block for cracks. If a crack is found, repair the cylinder block or replace the cylinder block.