MOTOR GP-PISTON 7Y4246 - Caterpillar

Illustration 1 g01116158
(1) Turbine wheel housing
(2) Compressor wheel housing
(3) Turbocharger oil lines
(4) Coolant lines for the turbocharger
(5) Wastegate for the turbocharger The condition of the turbocharger will have definite effects on engine performance. Use the following inspections and procedures to determine the condition of the turbocharger.
Inspect the turbine wheel and turbine wheel housing (1).
Inspect the compressor wheel and compressor wheel housing (2).
Inspect the oil lines for plugging (3).
Inspect condition of the coolant lines (4).
Inspect wastegate (5) for the turbocharger.Inspection of the Turbine Wheel and the Turbine Wheel Housing
Remove the air piping from the turbine housing.
Inspect the turbine wheel for damage by foreign material. If there is damage, determine the source of the damage. Replace the turbocharger. If there is no damage, go to Step 3.
Inspect the turbine wheel for buildup of carbon and other foreign material. Inspect the turbine wheel 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.
Turn the rotating assembly by hand. While you turn the assembly, push the assembly to the limits of the side-to-side end play. 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 housing. If there is no rubbing or scraping, go to Step 4.
Inspect the turbine wheel and the turbine wheel housing for oil leakage. Inspect the turbine wheel 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 found in the turbine wheel housing, go to "Inspection