Turbocharger Oil Leak and White Smoke [11/2021 - ]: Description

HINT: 

• Turbocharger oil leaks are classified into two types, internal oil leaks and external oil leaks.
• The following illustration shows the parts of the turbocharger.
• If an oil leak or white smoke occurs, sometimes the turbocharger is replaced even though it is not the cause of the problem.
• Oil may leak from the seal ring if the turbocharger is placed with its shaft vertical. However, this is unrelated to oil leaks during operation.
• Oil traces on the compressor housing surface or oil at the compressor inlet or outlet can mistakenly be evaluated as a leak from the turbocharger.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT: 

Oil staining, as shown in Illustration 1, may result from oil sprayed from turbocharger peripheral parts or oil leaks from the air cleaner hose. Oil staining on the outer surface of the turbocharger does not indicate an oil leak from the turbocharger. It is also unrelated to white smoke. To identify actual turbocharger external oil leaks, check only the seal areas shown in Illustrations 2 and 3.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT: 

• As the blow-by gas containing oil mist is returned to the intake system by the PCV, a certain amount of oil enters the intake system. The amount of oil at the compressor inlet shown in Illustration 2 is the normal amount and does not indicate an oil leak (internal oil leak) from the turbocharger. The amount of oil shown at the compressor outlet in Illustration 3 is also the normal amount.
• The surface of the compressor impeller may be blackened by the blow-by gas. This does not indicate a malfunction.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT: 

Illustration 4 shows how to check for air leaks from the position of an oil leak using soapy water. Bubbles form where the leak is occurring.

1. Faults and Symptoms of Turbocharger Parts 
   COMPRESSOR SIDE SEAL RING
   
   

   Main fault	Seal ring damage
   Symptom	Oil leak into compressor housing Excessive oil consumption
   Note	If the compressor seal ring is defective, a large oil leak may be found between the compressor outlet and the intercooler and between the intercooler and intake manifold. If a large oil leak is found in the compressor inlet, the oil did not come from the turbocharger. It may indicate a malfunction in the PCV system.

   TURBINE SIDE SEAL RING
   
   

   Main fault	Seal ring damage
   Symptom	Oil leak into turbine housing Large amount of white smoke emitted from the exhaust pipe Excessive oil consumption
   Note	If the turbine seal ring is defective, a large amount of white smoke is emitted continuously. If the white smoke is emitted only immediately after the engine is started and then disappears, or if a small amount of smoke is emitted intermittently, the oil did not come from the turbocharger. Another part may be defective. If wet oil is found at the turbine inlet, the oil did not come from the turbocharger. Another part may be defective.

   BEARING HOUSING (OIL DRAIN CLOGGING)
   
   

   Main fault	Blocked oil drain due to oil coking
   Symptom	Large amount of white smoke emitted from the exhaust pipe

   HINT: 

   • Oil coking results due to inadequate oil management
   • If the oil drain is blocked due to oil coking, the oil cannot be removed smoothly. Oil leaking from the bearing housing into the compressor housing and turbine housing generates a large amount of white smoke in the exhaust pipe.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *1	Oil Drain	-	-
   *a	Coked Oil	*b	Oil Drain Clogged with Coked Oil

   TURBINE SHAFT
   
   

   Main fault	Damage Seized
   Symptom	Shaft does not rotate Oil leak into compressor housing Large amount of white smoke emitted from the exhaust pipe Lack of power Abnormal noise from the turbocharger
   Note	A turbine shaft defect may cause a sensation of a lack of power due to inadequate boost pressure. At low temperatures, shaft rotation may feel heavy due to the oil viscosity. Do not mistake this for non-rotating shaft.

   COMPRESSOR IMPELLER
   
   

   Main fault	Damage
   Symptom	Shaft does not rotate Oil leak into compressor housing Lack of power
   Note	If the compressor impeller is defective, a large oil leak may be found between the compressor outlet and the intercooler and between the intercooler and intake manifold. The boost pressure may stop the oil at the compressor seal ring. If the boost pressure does not rise due to a damaged compressor impeller, oil flows into the compressor housing.

   COMPRESSOR HOUSING FIPG SEALING PART
   
   

   Main fault	Oil leak from the FIPG seal
   Symptom	If an oil stain is separate from the FIPG seal, it may be evaluated as oil sprayed from turbocharger peripheral parts. If the oil stain reaches the flange connector, it may be evaluated as a defective flange connection.

   INTAKE HOSES
   
   

   Main fault	Oil leak from the compressor inlet elbow and intake hose connector.
   Symptom	If oil stain traces exist at the hose or flange connector, it may be evaluated as a defective hose or flange connection.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *1	No. 2 Air Cleaner Hose	*2	Compressor Housing
   *3	Compressor Inlet Elbow	-	-
   *a	Oil Leak from Hose Connection Part	-	-