A.Mechanical seal mechanisam is normal

B.Sealing function is normal,the internal pressure of bearing housing is not higer than the air pressure at both ends,oil can not flow to the high pressure chamber from the low pressure chamber.

2.False oil leakage:refers to the pheonmenon of turbocharger oil leakage caused by non-quality problems

A. Turbocharger oil return was blocked to cause oil leakage at both ends of turbocharger.

B. Air filter was blocked or long time in idle speed to cause the negative pressure generated at compressor end which resulting in oil leakage.

C.Failure of oil-gas separator which caused the false appearance that oil leakage from turbocharger air inlet pipe.

Reminder: If the clearance of turbocharger rotation shaft is normal,please do not directly replace to the brand new turbocharger,please rule out all the possible scenariols as above,then can solve the oil leakage issue.