1985 300SD, 160k mile, Cal emission (recall performed), air-research (garett) turbo.

I have noticed oil on the turbo housing (see pictures). I remove the air intake, turbo looks good on that side but I found a little bit of oil in the intake. Probably coming from the blowby. I removed the blowby tubing and could not see any evidence of massive amount of oil, filter housing is clean no oil in there.
Is there a seal in the turbo between the impeller housing and the turbine itself? Could the seal be the problem?

Could not find a diagram or parts schematic of the turbo on the internet, I am pretty much certain that there is a seal somewhere between the front and aft section of the turbo but can't tell if this will explain the oil leak in this particular area....

Has anyone experienced a similar problem?

Thanks

Frederic

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Nothing there on my '84. No oil leaks either.

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83 SD

84 CD

My first guess would have been a slight leak at the gasket for the oil feed line to the turbo (right next to the area you have circled in red). This link might help sort things out: http://www.gpopshop.com/garrettt3kits.html

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Sam

84 300SD 350K+ miles ( Blue Belle )

SD blue,

Thank you very much for the link you posted.

I cleaned up the entire area around the housing and the leak is coming from the back of the compressor housing. The gasket around the oil line is dry.... Acording to the diagram you posted looks like there is a seal on the compressor side.
I will send the turbo for inspection.

Do you know, by any chance, if the oil drain line from the turbo can get obstructed over time? I was thinking that the leak could come from an over-pressurized oil in the turbo....At any rate, the seal would have to be changed. Just trying to find a possible reason for the seal to fail beside defect or aging.

thanks again
Frederic

Just thinking out loud, If the drain line became obstructed wouldn't we see a sudden turbo bearing failure from coking of the oil? From what I've read over a few years, here on this forum, there have been very few turbo failures on these cars.

Unless someone here has seen different, I would go along with your thinking of a seal that is starting to weep from aging. Maybe you caught it just in time and it turns out to be a less expensive repair, which is what he all hope for in coming across things like this. I've never worked on the turbo but posts here have said it is pretty simple if there isn't any damage to internals.

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Sam

84 300SD 350K+ miles ( Blue Belle )

A clogged Air Filter can cause a Turbo to leak (negative pressure pulls some Oil past the Seal when the Engine is at High rpms) as wells as plugged Oil drain tube (I have seen it on trucks); even a high Crankcase Oil level can sometimes cause it to leak.

And of course seal could need replacing to.
I was suprised to find that on the Garrett Turbos there is 3 different type of seals.

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84 300D, 82 Volvo 244Gl Diesel

Some more research on the net prompted me to find out that, as mentioned, the origination of the leak could come from a various amount of problems. Obstructed oil drain, bad or aging seal, improper seal mounting, worn out seal housing etc... Seems that, according to some web site, this is unfortunately not to uncommon. Interestingly enough, some oil leakage could occur at low engine rpm. Compressor not creating enough pressure at low rpm would permit the compressor seal to not be as effective....
I am out of town right now but my next experiment will be to clean up the oil on the housing and drive the car real slow for a couple of miiles and see if what happens.
At this stage i am going to remove the turbo and have it inspected anyway. Once removed i will be able to check the oil drain and replace some seals when i am at it.
I just hope that it is not a worn out seal housing...
Let you know when i find out.

Thanks again guys.