
RENR9968-02 37
Testing and Adjusting Section
1. Inspect the compressor wheel for damage from a
foreign object. If there is damage, determine the
source of the foreign object. As required, clean the
inlet system and repair the inlet system. Replace
the turbocharger. If there is no damage, go to
Step 3.
2. Clean the compressor wheel and clean the
compressor housing if you find buildup of foreig n
material . If there is no bu ildup of foreig n m aterial,
go to Step 3.
3. Turn the rotating assembly by hand. While you
turn the assembly, push the assembly sideways .
The assembly should turn freely. The compressor
wheel should not rub the compressor housing.
Replace the turbocharger if the compressor wheel
rubs the compressor wheel housing. If there is no
rubbing or scraping, go to Step 4.
4. Inspect the compressor and the compressor
wheel housing for oil leakage. An oil leak from
the compressor may deposit oil in the aftercooler.
Drain and clean the afte rcooler if you find oil in
the aftercooler.
a. Check the oil level in the crankcase. If the oil
level is too high, adjust the oil level.
b. Inspect the air cleaner element for restriction. If
restriction is found, correct the problem.
c. Inspect the engine crankcase breather. Clean
the engine crankcase breather or replace
the engine crankcase breather if the engine
crankcase breather is plugged.
d. Remove the oil drain line for the turbocharger.
Inspect the drain opening. Inspect the oil drain
line. Inspect the area betwee n th e b earings of
the rotating assembly shaft. Look for oil sludge.
Inspect the oil drain hole for oil sludge. Inspect
the oil drain line for oil sludge in the drain
line. If necessary, clean the rotating assembly
shaft. If necessary, clean the oil drain hole. If
necessary, clean the oil drain line.
e. If Steps 4.a through 4.d did n ot reveal the
source of the oil leakage, the turbocharger has
internal damage. R eplace the turbocharger.
Inspection of the Turbine Wheel
and the Turbine Housing
Remove the air piping from the turbine outlet casing.
1. Inspect the tu rbine for damage by a foreign object.
If there is damage, determine the source of the
foreign object. Replace the turbocharger. If there
isnodamage,gotoStep2.
2. Inspect the turbine wheel for buildup of carbon and
other foreign material. Inspect the turbine housing
for buildup of carbon and foreign material. Clean
the turbine wheel and clean the turbine housing if
you find buildup of carbon or foreign material. If
there is no buildup of carbon or foreign material,
go to Step 3.
3. Turn the rotating assembly by hand. While you
turn the a ss em bly, push the a ssem bly sideways.
The assembly should turn freely. The turbine
wheel should not rub the turbine wheel housing.
Replace the turbocharger if the turbine wheel rubs
the turbine wheel housing. If there is no rubbing or
scraping,gotoStep4.
4. Inspect the turbine and the turbine wheel housing
for oil leakage. Inspect the turbine and the turbine
wheel housing for oil coking. Some oil coking
may be cleaned. Heavy oil coking may require
replacement of the turbocharger. If the oil is
coming from the turbocharger center housing go
to Step 4.a.
a. Remove the oil drain line for the turbocharger.
Inspect the drain opening. Inspect the area
between the bearings of the rotating assembly
shaft. Look for oil sludge. Inspect the oil d rain
hole for oil sludge. Inspect the oil drain line
for oil sludge. If necessary, clean the rotating
assembly shaft. If nece ss ary, clean the drain
opening. If necessary, clean the drain line.
b. If crankcase pressure is high, or if the oil drain
is restricted, pressure in the center housing
may be greater than the pre ssure of the turbin e
housing. Oil flow may be forced in the wrong
direction and the oil may not drain. Check the
crankcase pressure and c orrect any problems.
c. If the oil drain line is damaged, replace the oil
drain line.
d. Check the routing of the oil drain line. Eliminate
any sharp restrictive bends. Make sure that
theoildrainlineisnottooclosetotheengine
exhaust manifold.
e. If Steps 4.a through 4.d did not reveal the
source of the oil leakage, the turbocharger has
internal damage. Replace the turbocharger.