Oil Burning

[Caduceus]

Hi guys,

Just wondering what could be wrong and what I could do to fix my car. It's putting out alot of oil smoke out of the exhaust only at idle, and only after it's been idling for a while. when I rev then engine it goes away after a few seconds. Are valve stem seals hard to replace? And what is in the turbo that can be overhauled? Anything else, other than piston rings, that would contribute to this?

1982 300D Turbo running amsoil 5w40 Diesel Oil. Problem just recently started.

Thanks

[TMAllison]

Is your Amsoil syn or dino oil?

Have you tried changing to a little higher viscosity?

[Caduceus]

Originally Posted by TMAllison

Is your Amsoil syn or dino oil?

Have you tried changing to a little higher viscosity?

Synthetic, what diesel rated synthetic is higher than 40?

[t walgamuth]

I would try rotella straight thirty weight dino oil and change it every three thousand miles.

On a tired engine the synthetic is too thin and too expensive, it will likely use less of the thicker dino oil.

Tom W

[Diesel911]

Originally Posted by Caduceus

Hi guys,

Just wondering what could be wrong and what I could do to fix my car. It's putting out alot of oil smoke out of the exhaust only at idle, and only after it's been idling for a while. when I rev then engine it goes away after a few seconds. Are valve stem seals hard to replace? And what is in the turbo that can be overhauled? Anything else, other than piston rings, that would contribute to this?

1982 300D Turbo running amsoil 5w40 Diesel Oil. Problem just recently started.

Thanks

What is inside of the turbo: I have not been inside of a Mercedes turbo but the in other Air Research type turbos I have seen the compressor (intake) side and the exhaust side both have at least 1 piston ring type seal; the piston ring and the groove it rides in wears out and your turbo will leak oil, there is one full floating bearing on each side (made of bronze or aluminum) and the turbine shaft bearing journal and the bore in the bearing housing wear increasing the side (axial) play , oh the compressore side behind the compressor turbine is the collar that the piston ring seal rides in and steel thrust plate and a thrust bearing (both wear increasing the end play/thrust). Additionaly oil leakage can be caused by high crankcase pressure and a bolcked turbo oil drain tube or if the crankcase oil level is so high that it blocks off the oil drain outlet.

[Diesel911]

Did Caduces say if the crank case oil level was getting lower and he/she had to add oil frequently? When the engine oil filler cap is removed from the valve cover and the engine is idled as described is there a lot of blow by comming out of the oil fill hole? (Alot of blow by could indicate worn exhaust valve stems+guids as well as worn piston/rings/cylinders.)
Harbor Freight sells cheap diesel compression gauge sets.