Oil present on exhaust side of the Turbo, Where is that oil coming from
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Junior Member
Joined: May 2018
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2012 GL350 Bluetec
Oil present on exhaust side of the Turbo, Where is that oil coming from
I have a 2012 Mercedes Benz GL350 Bluetec, Rebuilt Turbo, Changed Oil separator part already that feeds into the side of the Turbo intake pipe.. I have new gasket for turbo and seals etc installed. I have oil leaking on the exhaust side of the turbo turbine somehow. Where would that oil be coming from ? Also i am looing for procedure on how to remove intercooler and drain oil from it just incase there is some in there as well. IS there a quick access on sticking a thin pipe down there to suck the oil out if present. Need help with picture or diagrams or step on how to get to the intercooler to rule that out as possible source of oil into turbo ?
MBWorld Fanatic!
Joined: Jan 2010
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NGL450 w/EORP, S550
Oil on the exhaust side is usually because of a blown seal on the turboshaft. If you’re able to grab the impeller and the turbine and try to move it side to side or radially there shouldn’t be any movement and it should rotate freely. If you feel any movement that is where the oil is getting out of the seal/bearing on the exhaust side.
Now if oil is getting any of your exhaust from the turbo side it should be getting burnt and there will be lots of smoke… So can you please clarify this it doesn’t quite make sense in my head?
Typically on the intake side if your turbo is puking oil it is either the seal on the intake/impeller, but sometimes also a overpressurized crank case because of a faulty PCV valve will pressurize the crank case on boost and fill the intake side with oil - while that may not be your problem, unless you find oil in the inter cooler; but these are typically the two manifestations of oil in and around the turbo piping on the impeller and/or turbine side.
Now if oil is getting any of your exhaust from the turbo side it should be getting burnt and there will be lots of smoke… So can you please clarify this it doesn’t quite make sense in my head?
Typically on the intake side if your turbo is puking oil it is either the seal on the intake/impeller, but sometimes also a overpressurized crank case because of a faulty PCV valve will pressurize the crank case on boost and fill the intake side with oil - while that may not be your problem, unless you find oil in the inter cooler; but these are typically the two manifestations of oil in and around the turbo piping on the impeller and/or turbine side.
Last edited by Max Blast; Aug 10, 2022 at 09:29 PM.
