On my 1982 300D turbo (200K miles) I used to add about a quart of oil every 2000 miles. recently oil consumption has gone up to more than 1qt every 1000 miles. i went on a crusade to fix external oil leaks but not too much was leaking. When i take off the oil fill cap it puffs like a choo choo train so i think the blow by is excessive. The air filter was getting drenched with oil on one side (I resealed the leaky oil trap cover with silicone) the exhaust tail pipe has a thick coat of soot as well. Oil trap drain is open (I poured oil down it to check). I noticed some oil around two of the head bolts (star heads). thinking it was the valve cover i cleaned them off but a small amount of oil reappeared back at the two head bolts. Should i retorque the head? Could that be the oil burn problem?

I plan on pulling the glow plugs to see if there is oil associated with one of the cylinders more than another.

I bought the car 30k miles ago from the original owner. About 50K miles ago the PO's mechanic (The Diesel Stop, in San Gabriel, now out of business) replaced the piston rings, main & rod bearings, head & flywheel bolts. Also grind crank, re-size rods. Compression after work completed was noted as 300, 280, 300, 320, 280. Complaint was excessive noise and low oil pressure.

Maybe unrelated but the engine shakes more at idle. I adjusted the rack bolt but no difference. Power is still OK with engine.

Any suggestions?

Thanks

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1972 450SL
1982 300D Turbo

Those are very poor numbers for having new rings. (I wonder why they are no longer open???) Unless it still needed a valve job after the rings were done, all the cylinders should be in the 350-450+ range. The cylinder head was off and they were doing so much work to it already, a valve job should have been done at the same time.

With only 50k miles, there should be no reason for the head to leak if the job was done right. Mabye they didn't re-torque the head after it was run to operating temp???

I doubt torquing the head bolts will do much,but you can try. Have you done a compression test now, or are those numbers from right after the rebuild? It sounds like the rebuild has some issues.

If those numbers were from right after it was put together then they sound about right. You need to put at least 500miles on them to get the rings seated and "broken in" properly.

"When i take off the oil fill cap it puffs like a choo choo train"
That's not *always* a bad sign. I know quite a few MB diesel engines that have blow-by like that and run very well (My 320K mile engine, for example, can still start without a block heater on 0*f days). All engines are going to have some blow-by no matter the age, miles, or design.

"the exhaust tail pipe has a thick coat of soot as well"
Part of the diesel life. I can't think of a pre-2002 diesel exhaust that has no soot in the tailpipe.

"I adjusted the rack bolt but no difference."
Is the rack damper a kind of gold color? If it's not, it could be the old style with a weak spring. What RPM do you idle at?

but what kind and weight of oil are you using?

also those numbers are normal if the compression was tested cold.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Others on this forum have mentioned turbo seal failure with such high oil consumption. If I recall, not very expensive to repair with a kit.

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Sam

84 300SD 350K+ miles ( Blue Belle )

Retorquing the head won't buy you anything.

In fact, I'd bet that the oil that you see around the head bolt remains from the leaking valve cover. They can be a PITA to seal completely and the proper torque on the nuts is critical.

If you are getting an extraordinary amount of oil in the air cleaner and blowby is high, the chances are good that the bottom end is marginal and the oil is passing to the engine via the breather.

As mentioned, it's also likely, on high mileage engines, that the turbo seals leak some oil as well.

The combination of high blowby and leaking turbo seals will result in some serious consumption.

This one has very little blowby but is consuming a quart every 1500 miles...........most likely due to the turbo seals.

Started new post with results of Brian Carlton's suggested experiment.

http://www.peachparts.com/shopforum/showthread.php?p=1153029#post1153029

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1972 450SL
1982 300D Turbo