CAP-BEARING 4314601 - Caterpillar

Inspection of the Turbine Wheel and the Turbine Housing
Remove the air piping from the turbine housing.
Inspect the turbine for damage by a foreign object. If there is damage, determine the source of the foreign object. Replace turbocharger (3). If there is no damage, go to Step 2.
Inspect turbine wheel (2) for buildup of carbon and other foreign material. Inspect turbine housing (1) for buildup of carbon and foreign material. Clean turbine wheel (2) and clean turbine housing (1) if you find buildup of carbon or foreign material. If there is no buildup of carbon or foreign material, go to Step 3.
Turn the rotating assembly by hand. While you turn the assembly, push the assembly sideways. The assembly should turn freely. Turbine wheel (2) should not rub turbine wheel housing (1). Replace turbocharger (3) if turbine wheel (2) rubs turbine housing (1). If there is no rubbing or scraping, go to Step 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”.
Remove the turbocharger oil drain line. 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 rotating assembly shaft. If necessary, clean the drain opening. If necessary, clean the drain line.
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.
If the oil drain line is damaged, replace the oil drain line.
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.
If Steps 4.a through 4.d did not reveal the source of the oil leakage, turbocharger (3) has internal damage. Replace turbocharger (3). Testing The Wastegate
If the valve of the wastegate does not operate at the correct pressure, the performance of the engine will be adversely affected. If the valve opens at a pressure that is too low, the following items will occur: black exhaust smoke and loss of power at lower engine rpm. If the valve opens at a pressure that is too high, pressures in the engine cylinders will be too high. Cylinder pressures that are too high will cause the following items to occur: failure of the cylinder head gasket and damage to the bearings and the pistons.
Illustration 2 g00323911
The wastegate is mounted on the turbocharger.
(1) Dial indicator
(2) Clip
(3) Pin
(4) Actuator rod
(5) Locknut
(6) Actuator
(7) Line for the boost sensor
Disconnect the line for the boost