View Single Post
Old 05-12-2002, 12:58 AM
gsxr's Avatar
gsxr gsxr is offline
Join Date: Aug 2001
Location: USA
Posts: 8,102
Here's the latest:

I took Peter K's advice and pulled the intake crossover pipe with the engine warm. I let it idle for a couple minutes with it off, then revved the engine. Same big blue cloud out the exhaust, no oil or oil vapor appearing from the turbo pipe (just a cool roaring noise as it spools up). So, even though I get quite a bit of oil in the intake, I guess it's "normal". I did read a tidbit in the OM603 folder on the MB CD-ROM that essentially said some oil is normal in there, but that's kind of vague. I suppose the point is don't expect it to be dry. (There's other cool info in the subfolders, check it out, updates & recalls etc...)

So, that means the oil leak coming from the head, not the intake. The "thumb" test is useless on this car - there's almost zero airflow from the valve cover hole, I could hold my thumb over it all day and just get a burned thumb, the engine would never shut down. I don't think there is much blowby, and I'm presuming minimal oil passing the rings. It has to be coming from either the valve seals or a pressurized oil passage.

Now, the only area of the head gasket that has a *pressurized* oil passage is right up front, between cyl #1 and the timing chain area. Every other passage is a drain (no pressure). There is a plug in the exhaust manifold by cyl #1, I pulled it out to inspect, it was bone dry and carboned up - i.e., normal. I stuck a Q-tip down the hole, wiggled it, still dry - no sign of oil. So, it appears that I either have a problem with cyl #6, and possible some other cylinders, but #1 might be OK. Have to yank the exhaust to find out (ugh - not doing that for a while.) I can also look at the valve seals to see if they put them in backwards on one cylinder. This requires pulling the cam, not as bad a job as the manifold would be. I might try that first.

Question: Is it possible to install the int/exh seals "backwards" (intake seal on exhaust valve, and vice-versa), and if so, wouldn't the symptoms be MUCH worse than I have now? Remember, there's no throttle plate to induce vacuum to suck oil past the seals - it has to be a gravity feed, I guess. Or would the boost (or exhaust) force gasses back into the crankcase...? Hmmmm.... My head hurts...

Best regards,
Boise, ID

Check out my website photos, documents, and movies!
Reply With Quote