Inspection of the Turbine Wheel and the Turbine Housing

TM 9-2320-312-24-2

Testing and Adjusting Section

b. If crankcase pressure is high, or if the oil

d. Remove the turbocharger oil drain line.

drain is restricted, pressure in the center

Inspect the drain opening. Inspect the oil

housing may be greater than the pressure of

drain line. Inspect the area between the

the turbine housing. Oil flow may be forced in

bearings of the rotating assembly shaft. Look

the wrong direction and the oil may not drain.

for oil sludge. Inspect the oil drain hole for

Check the crankcase pressure and correct

oil sludge. Inspect the oil drain line for oil

any problems.

sludge in the drain line. If necessary, clean

the rotating assembly shaft. If necessary,

c. If the oil drain line is damaged, replace the

clean the oil drain hole. If necessary, clean

oil drain line.

the oil drain line.

d. Check the routing of the oil drain line.

e. If Steps 4.a through 4.d did not reveal the

Eliminate any sharp restrictive bends. Make

source of the oil leakage, the turbocharger has

sure that the oil drain line is not too close to

internal damage. Replace the turbocharger.

the engine exhaust manifold.

Inspection of the Turbine Wheel

e. If Steps 4.a through 4.d did not reveal the

and the Turbine Housing

source of the oil leakage, the turbocharger has

internal damage. Replace the turbocharger.

Remove the air piping from the turbine outlet casing.

Inspection of the Wastegate

1. Inspect the turbine for damage by a foreign

object. If there is damage, determine the source

The turbocharger senses boost pressure which

of the foreign object. Replace the turbocharger.

actuates the wastegate valve. The wastegate valve

If there is no damage, go to Step 2.

controls the amount of exhaust gas that is allowed

to bypass the turbine side of the turbocharger.

2. Inspect the turbine wheel for buildup of carbon

Regulating the amount of exhaust gas that enters the

and other foreign material. Inspect the turbine

turbocharger regulates the rpm of the turbocharger.

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 assembly, push the assembly 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, go to Step 4.

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. Otherwise go to "Inspection of

the Wastegate".

g00295815

Illustration 57

a. Remove the turbocharger oil drain line.

Typical Example

Inspect the drain opening. Inspect the area

(1) Actuating Rod

between the bearings of the rotating assembly

(2) Canister

shaft. Look for oil sludge. Inspect the oil drain

(3) Line

hole for oil sludge. Inspect the oil drain line

for oil sludge. If necessary, clean the rotating

When the engine operates in conditions of low boost

assembly shaft. If necessary, clean the drain

(lug), a spring presses against a diaphragm in

opening. If necessary, clean the drain line.

canister (2). This moves actuating rod (1) in order to

close the wastegate valve. Then, the turbocharger

can operate at maximum performance.