Fault Phenomenon: Caterpillar AP655D paver engine oil sprays from the exhaust, oil leaks from the turbocharger shaft.

Troubleshooting Process:
– Checked oil return line: turbocharger oil return line clogged.
– Checked seal rings: floating seal rings worn.
– Checked intake: air filter clogged causing high intake vacuum.
– Checked crankcase: breather clogged.

Root Cause: The turbocharger oil return line is clogged, causing excessive oil pressure in the bearing housing, leading to leakage past the seal rings.

Required Parts: Clear or replace turbocharger oil return line, inspect seal rings.