TM 5-3805-280-24-2
Air Intake and Exhaust System Operation and Tests
DIAGNOSING TURBOCHARGER MALFUNCTIONS
110
10
Excessive crankcase pressure.
Before replacing the turbocharger, determine what
Air intake restriction.
caused the failure of the defective unit, and correct the
Drain tube restriction.
condition. This will prevent an immediate repeat failure
of the replacement unit. Refer to Air Intake and
Oil In Manifold Or Dripping From Housing:
Exhaust System Group 30 for repair information.
Noise Or Vibration1 :
Excessive crankcase pressure.
Air intake restriction.
Bearings not lubricated (insufficient oil pressure).
Drain tube restriction.
Air leak in engine intake or exhaust manifold.
Damaged or worn journal bearings.
Improper clearance between turbine wheel and
Unbalanced rotating assembly:
Damage to turbine or compressor wheel or blade.
turbine housing.
Dirt or carbon build-up on wheel or blade.
Broken blades (or other wheel failures).
Bearing wear:
Engine Will Not Deliver Rated Power:
Oil starvation or insufficient lubrication.
Shaft seals worn.
Clogged manifold system.
Foreign material lodged in compressor, impeller, or
Turbine Wheel Drag:
turbine.
Excessive dirt build-up in compressor.
Carbon build-up behind turbine wheel caused by
Leak in engine intake or exhaust manifold.
Leak in intake manifold-to-aneroid pipe.
coked oil or combustion deposits.
Dirt build-up behind compressor wheel caused by air
Rotating assembly bearing failure.
Damaged compressor or turbine blades.
intake leaks.
Bearing seizure or dirty, worn bearings caused by
excessive temperatures, unbalanced wheel, dirty oil,
Oil On Compressor Wheel Or In Compressor
oil starvation, or insufficient lubrication.
Housing (Oil Being Pushed or Pulled Through
Center Housing):
1
Do not confuse the whine heard during run down with noise which
indicates a bearing failure.
RG,110,JW7670
1924NOV971/1
13-516
