Turbocharger Troubleshooting Guide

Bearings scored from lack of oil supply or bad oil / contamination

Bearing failure

 

Scored bearing on turbine wheel. See shaft is blue from getting hot from lack of oil lubrication

Cracked turbine housing at exhaust inlet

Cracks in trubine housing inside housing

Internal turbine housing cracks

Burst compressor wheel

Foreign object damage to compressor wheel

Compressor wheel failure after scrubbing walls of compressor cover, secondary failure after bearings have failed

 

Exhaust bypass cracks

Compressor wheel scrubbing compressor cover

Foreign object damage on compressor inlet

Foreign object damage on compressor inlet

Thrust bearing stack up

Example of thrust bearing cracks and damage

Thrust bearing scoring and damage

Piston ring damage and bearing journal damage from lack of proper oil supply

Broken turbine wheel and shaft from abrupt stop

Broken turbine wheel blade from foreign object damage, most likely from an engine valve or piston

Foreign object damage from engine

Damage to turbine wheel from scrubbing turbine housing

Vanes on variable vane geometry turbo

Damage to vanes on variable vane geometry turbo

Turbocharger air flow diagram

Possible Failure Diagnosis Engine Running Hot Poor Transient Response Smoke Engine Lacks Power Black Exhaust Smoke Blue Exhaust Smoke High Oil Consumption Turbocharger Noisy Cyclic Sound from the Turbocharger Oil Leak from Compressor Seal Oil Leak from Turbine Seal
Dirty air cleaner Clean or replace element according to manufacturer’s recommendations
Restricted compressor intake duct Remove restriction or replace damaged parts as required
Restricted air duct from compressor to intake manifold Replace seals, gaskets or tighten fasteners as required
Restricted intake manifold Refer to engine manufacturer’s manual and remove restriction
Air leak in feed from air cleaner to compressor Replace seals, gaskets or tighten fasteners as required
Air leak in feed from compressor to intake manifold Replace seals, gaskets or tighten fasteners as required
Air leak between intake manifold and engine Refer to engine manufacturer’s manual and replace gaskets or tighten fasteners as required
Foreign object in exhaust manifold (from engine) Refer to engine manufacturer’s manual and remove obstruction
Restricted exhaust system Remove restriction or replace damaged parts as required
Exhaust manifold cracked, gaskets blown or missing Refer to engine manufacturer’s manual and replace gaskets or damaged parts as required
Gas leak at turbine inlet/exhaust manifold joint Replace gasket or tighten fasteners as required
Gas leak in ducting after turbine outlet Refer to engine manufacturer’s manual and repair leak
Restricted turbocharger oil drain line Remove restriction or replace damaged parts as required
Restricted engine crankcase breather Refer to engine manufacturer’s manual, clear restriction
Turbocharger bearing housing sludged or coked Change engine oil and oil filter, overhaul or replace turbocharger as required
Fuel injection pump or fuel injectors incorrectly set Refer to engine manufacturer’s manual and replace or adjust faulty components as required
Engine valve timing incorrect Refer to engine manufacturer’s manual for correct settings and adjust as required
Worn engine piston rings or liners Refer to engine manufacturer’s manual and repair as required
Burnt valves and/or pistons Refer to engine manufacturer’s manual and repair as required
Excessive dirt build-up on impeller and/or diffuser vanes Clean in accordance with the appropriate manufacturer repair manual
Turbocharger damaged Find and correct cause of failure, repair or replace turbocharger as necessary
Failed diaphragm Replace using correct Actuator Service Kit
Siezed valve Free valve/replace complete turbine housing sub-assembly
Leaking hose Replace hose and clips
Wastegate mechanism set incorrectly