Perkins 1106C Genset Systems Operation Testing And Adjusting page 52

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Testing and Adjusting Section
d. If Steps 3.a through 3.c did not reveal the
source of the oil leakage, the turbocharger has
internal damage. Replace the turbocharger.
Inspection of the Turbine Wheel
and the Turbine Housing
Remove the air piping from the turbine housing.
1. Inspect the turbine for damage by a foreign object.
If there is damage, determine the source of the
foreign object. Replace turbocharger (2). If there
is no damage, go to Step 2.
2. Inspect the turbine wheel for the carbon and
other foreign material. Inspect turbine housing
(1) for carbon and foreign material. Replace the
turbocharger, if necessary. 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 assembly, push the assembly sideways.
The assembly should turn freely. The turbine
wheel should not rub turbine wheel housing (1).
Replace turbocharger (2) if turbine wheel rubs
turbine housing (1). If there is no rubbing or
scraping, go to Step 4.
4. Inspect the turbine and turbine housing (1) for oil
leakage. Inspect the turbine and turbine housing
(1) 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.
Otherwise go to "Inspection of the Wastegate".
a. Remove the pipe for the oil drain. Inspect the
drain opening. Inspect the area between the
bearings 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.
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 pressure of turbine
housing (1). Oil flow may be forced in the wrong
direction and the oil may not drain. Check the
crankcase pressure and correct 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
the oil drain line is not too close to the engine
exhaust manifold.
e. If Steps 4.a through 4.d did not reveal the
source of the oil leakage, turbocharger (3) has
internal damage. Replace turbocharger (3).
Inspection of the Wastegate
The wastegate controls the amount of exhaust gas
that is allowed to bypass the turbine side of the
turbocharger. This valve then controls the rpm of the
turbocharger.
When the engine operates in conditions of low
boost (lug), a spring presses against a diaphragm
in the canister. The actuating rod will move and the
wastegate actuator will close. The turbocharger can
then operate at maximum performance.
When the boost pressure increases against the
diaphragm in the canister, the wastegate will open.
The rpm of the turbocharger becomes limited. The
rpm limitation occurs because a portion of the
exhaust gases bypass the turbine wheel of the
turbocharger.
The following levels of boost pressure indicate a
problem with the wastegate:
•
Too high at full load conditions
•
Too low at all lug conditions
The boost pressure controls the maximum rpm of the
turbocharger, because the boost pressure controls
the position of the wastegate. The following factors
also affect the maximum rpm of the turbocharger:
•
The engine rating
•
The horsepower demand on the engine
• The high idle rpm
•
Inlet air restriction
•
Exhaust system restriction
Check the Wastegate for Proper
Operation
Table 5
Required Tools
Part
Tool Number
21825617
A Dial Gauge
KENR6931
Part Description Qty
1