I acquired a 1989 300ce with 120,000 miles on it last December. I didn’t know the car had an extreme drinking problem when I bought it. It’s going through a quart of synthetic oil around 200 miles. The obvious diagnosis would be a new set of Valve Stem Seals but it doesn’t have all symptoms you would expect to see with bad seals.

I haven’t noticed any smoke coming out the back, it passed CA smog a month ago, there’s no oil on the tip of the tail pipe and no exhaust smoke residue on the paint. The car is not leaking motor oil and there is no oil in the water.

The only solid symptom I’ve noticed that points to bad valve stem seals is the sparkplugs. The plugs that were in the car were caked with gunk and wet with oil. I changed the plugs and rechecked them after I drove 30 miles and the plugs were wet and smelled like burnt oil and gas i.e. rich. Also the exhaust smells rich to me

I’m going to do a couple of thing to better pin-point the diagnosis. I’m going to have a friend follow me on the freeway to find out if it’s blowing smoke I can't see at hwy speeds. I’m also going to check the rings with a compression test. Can anyone suggest any other simple test I can do to diagnose my oil-oholic car before I dig into the motor?

I found a good post on this topic at http://mbworld.org/forums/e-class-w1...s-my-300e.html and the post had instructions on how to change the valve stem seals on a 1992 300E http://www.mercedesshop.com/Wikka/M103ValveSeals
Does anyone know if these repair instruction would be the same for my 1989 300ce

Thank you,

 

Yes, both are the m103 12 valve engine.

Do the valve stem seals but first check passenger side rear of engine block for oil leak. At 120k thes engines are over due for a head gasket. Good luck

 

Smedley, thanks for the heads up

 

Before I dig into the motor, I'm going to try a "hot soak" with Seafoam and also flush the crankcase with SF - hopefully I'll get lucky. I did 14 hour hot soak with Seafoam on my old 1989 535is BWM. That Bemmer smoked like Cheech & Chong for 2 days and pissed off a few fanatical greenies. The car ran noticeably better, got better gas mileage and the stuff is EPA approved in CA.

http://video.google.com/videoplay?do...=seafoam&hl=en