- Failed turbocharger seals
- Worn valve guide seals or faulty valve guide seals
- Worn valve guides
- Worn piston rings
- Scored cylinder liners or worn cylinder liners
Check the inlet manifold and the exhaust manifold for oil. If oil is present, replace the turbocharger.
Inspect the valve guide seals for wear and for damage. Replace the valve guide seals, if necessary.
Inspect the valve guides for wear. Refer to the Specification manual for the maximum permissible wear of the valve guides. If necessary, recondition the cylinder head.
Piston rings that have excessive wear can cause too much pressure in the crankcase. The additional pressure in the crankcase will cause more than the normal amount of crankcase blowby from the crankcase breather. Use the 8T-2700 Blowby/Air Flow Indicator to check the amount of crankcase blowby. The test procedure is in Special Instruction, SEHS8712. Inspect piston rings and install new parts, as required.
Inspect the cylinder liners for damage. Hone the cylinder liners in order to remove the scoring. If necessary, install new liners.