Where's my oil going??
 

This is not a Mercedes question, but I need a bit of help on my sons engine. We recently rebuilt his 400 chevy small block. It's been running great, with one issue I can't seem to track down. After about 1000 miles, it is using about 1 qt in 400 miles. I assumed the rings hadn't seated, but they should be after 1000 miles. The engine runs great, doesn't smoke. I checked the plugs this weekend and they are all a very nice tan, no soot. I'll be doing a leakdown check this coming weekend, but I thought that someone might have a suggestion.

Valve guide oil seals, maybe.

Did you re-bore the engine or just hone and replace rings? If you did re-bore then I too suggest you check the valve stem seals and make sure they are seated properly and were not damaged on imstallation. If you just honed the cylinders and put in standard rings - the cylinders could be slightly out of round and requiring the rings to run another 1000 - 2000 miles to seat properly.

Thanks for the replies. I did have it bored .030" and honed, and hand filed the rings. I bought new heads fully assembled, but didn't check the seals. I assumed they were correct. It seems like it must be leaking while running, as there is never any oil under it after it sits, but I don't see any oil on the underbody anywhere. I'll look into the valve guide seals, and watch it for a while yet. Thanks again.

Hand filed the rings
 

My guess would be the rings have not seated yet, would think you'd see some discoloration in the exhaust though.

Good luck,
Joel