I have a BIG oil consumption problem on my 1981 300D of a scale that I have not seen. This car uses about a quart of oil every 200 miles. I am 99% sure that it is not burning as this level of consumption would be leaving a smoke screen everywhere I go. Also, I have I stood behind this car while it is running and there is no hint of oil burning. When I park the car I am not seeing oil dripping of any kind. The engine in general is dirty, but I have just not found a ‘smoking gun’. Perhaps I should first try to degrease the engine and see what develops. This is new territory for me as I have never owned a vehicle that ever lost more than 1/2 of a quart in 4,000 miles. Does anyone have any hints and history for this type of issue?

try tracerline. it is a flourescent additive that will show up leaks - add it to oil next time you top up. their website has different additives for different applications.

i haven't used it but i've heard recommendations

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'88 190E 2.6

A diesel can burn a lot of oil before there is much tell-tale in the exhaust. However, 1qt./200 miles should have some sort of trail.

For this amount of consumption, it may be a combination of things. Valve seals, turbo seals, main seals etc...

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Sam

84 300SD 350K+ miles ( Blue Belle )

I changed the oil in Madeline and the oil consuption seems to be way down.
Can this actually happend? I would understand if it had a very, very light oil in it that the loss could be great, however, I don't think that what was drained out was necessarily a thin oil.

I was going to suggest trying a thicker oil. I don't know what was in mine when I bought it, but it used about 1 qt. / 600 miles or so. Now I use Rotella 15w-40 every 3000 miles and it consumes very little of it. 1 qt. / 200 miles is a lot though.

How long have you had Madeline? Is this a new-to-you car or do you have a history and this started recently?

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Sam

84 300SD 350K+ miles ( Blue Belle )

I have had Madine only about 3 months. I don't think that I have put 800 miles on her. The car is road worthy, but still needs some work.

Well, so far after 300 miles on the new oil the level seems to be staying where it should. I have never seen anything like this before. But, the good part is I am not needing to track my MPG of the oil.

That's good news! Maybe the PO had it filled with a very light synthetic?

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Sam

84 300SD 350K+ miles ( Blue Belle )