MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES
454
Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited
Section III Inspection and Repair
The turbocharger is a precision machine rotating at a high speed. Its maximum rotation speed can reach
210000 r/min or more and its normal speed is always above 10000
– 100000 r/min. Therefore, if not
necessary, the turbocharger assembly should not be disassembled arbitrarily. When the turbocharger
rotator rotates inflexibly or the diesel engine performance deteriorates due to dust and carbon deposits,
simple clearing and cleaning can be conducted to the turbocharger without complete disassembling. The
detailed methods are as follows :
(1) Clean the dust and fuel dirts on the surface of the turbocharger.
(2) Remove the turbocharger from the diesel engine and pay attention not to lift the turbocharger by
utilizing the linkage push rod as a handle.
(3) Remove the air guide pipe first and then the adjusting device of the air release valve.
(4) Remove the gas compressor housing, the turbine housing, and the parts connecting the fuel inlet
pipe and return hose and the coolant pipe.
(5) Clear and clean the gas compressor housing, the turbine housing and 2 turbine impeller surfaces.
(6) Fill an appropriate amount of the cleaning agent via the fuel inlet port, and rotate the impeller by
hands repeatedly till it rotates flexibly.
(7) Assemble the turbocharger and install it in the diesel engine. When installing the turbocharger, all the
packings connected with the turbocharger should be replaced and the clean lubricating oil should be
filled through the turbocharger fuel inlet port for lubrication.
Caution:
Do not touch and strike the impeller during the removing and cleaning for the
turbocharger. If there is any touch, the deformed impeller blade can not continue to be used even after
the correction. The cleaning agent can be kerosene, gasoline or diesel of good quality.
If excessive abrasion and damage of the turbocharger are found during checking, the wear and
damaged parts should be adjusted, repaired or replaced.
Fig. 9-3-1 Checking the working condition of the
exhaust outlet
1. Checking the working condition of the
exhaust outlet
(1) Remove the hose between the exhaust outlet
and the intake pipe.
(2) Connect the pressure gauge.
(3) Check whether the connecting rod starts to
move or not when an approximate 0.088Mpa
pressure is applied at the exhaust outlet. See Fig.
9-3-1.
Attention:
For this kind of check, the
pressure should not be above 0.1Mpa.
Connecting rod
Pressure
