I am working on a '93 S350. The car has just under 100K. I did a compression test on it and cylinders 2-5 are about 495lbs. Cylinder 1 is 440 and cylinder 6 is 450. It also seems to use a fair amount of oil. I also attached a picture showing the amount of buildup at the egr. What are your thoughts on this? Is it most likely suffering the rounded out cylinder woes? Just keep driving until oil consumption gets too much?

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05 SL600 75K
87 MB 560SL 119K
87 MB 300D 180K
83 MB 240D 110K
64 1/2 Mustang
74 Monte Carlo 32K
75 Fiat 124 Spyder
16 Equinox
15 2500HD Silverado

Carbon will build in the EGR. you still have good compression so I dont think there's a big problem yet. how much is it using in say 3000 miles? if it's not too bad keep driving it, check your turbo seals too. they fail and your eating engine oil.

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hum.....
1987 300TD 311,000M Stolen. Presumed destroyed

I haven't driven it a whole bunch, but I would guess it's using a quart every 500 miles. What is the best way to check the turbo seals?

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05 SL600 75K
87 MB 560SL 119K
87 MB 300D 180K
83 MB 240D 110K
64 1/2 Mustang
74 Monte Carlo 32K
75 Fiat 124 Spyder
16 Equinox
15 2500HD Silverado

92-93 300SD or 94-95 S350. Good thing JimmyL focuses on stray T's

That's as bad as I've seen soot in the mixing pipe. Does it get out of its own way?

There might be an easier way to test turbo seals on the compressor side but one way is to disconnect the hose from the valve cover to the turbo air inlet and cap the port on the turbo air inlet. Clean the compressor housing and vanes with brake parts cleaner then go for a drive to see if the compressor housing gets oily again. If it isn't oily in the first place, there's probably no issue with the seal.

Lower compression in #1 and #6 reminds me of the bent rods in my 93 SD but could 'just' be a leaky head gasket.

A quart in 500 miles isn't too much?

Sixto
87 300D

You have bent rods. Guess how I know? Drive car until you get ready to address the bent rods. Looking elsewhere to solve your problem is wishful thinking, which hardly ever get you anywhere working on a Mercedes car. Ask me how I know? Hopefully, I just saved you a couple thousand dollars and prevented you from doing as I did, which was solve every other problem that it was possible to solve on the motor to stop the excessive oil usage and backed into the bent rods after there was nowhere else to go, which I had been wishing and hoping that the rods weren't bent, since the car was driving so good as it was dranking oil almost as much as fuel.

BenzDiesel

Yeah, that is what I am thinking/afraid of. (It is a '94 S350 to clarify - manufactured 11/93). I am going to put it back together after cleaning up the intake and will double check the turbo seals as mentioned. I'll post what I find!

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05 SL600 75K
87 MB 560SL 119K
87 MB 300D 180K
83 MB 240D 110K
64 1/2 Mustang
74 Monte Carlo 32K
75 Fiat 124 Spyder
16 Equinox
15 2500HD Silverado

Okay - finally back from vacation! I cleaned up the intake and turbo and reassembled everything except I left off the crossover pipe from the turbo to the intake. I started the car and let it warm up a bit. I reved up the engine and held my hand over the turbo and it does have a lot of oil in the air stream and after I shut it off, you could see the oil running down the turbo. So, It does look like the oil seals are leaking within the turbo. I looked on fastlane for turbo and all they list is a turbo o-ring seal. how hard is it to rebuild the turbo verses buying a rebuilt one, and where can I get a rebuilt one?

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05 SL600 75K
87 MB 560SL 119K
87 MB 300D 180K
83 MB 240D 110K
64 1/2 Mustang
74 Monte Carlo 32K
75 Fiat 124 Spyder
16 Equinox
15 2500HD Silverado

The turbo cannot be rebuilt by the average owner, a specialized shop needs to do it for it to be done correctly. If there is no damage to the wheels or shaft it shouldn't cost more than $150.