1988 300 SEL, 208K mi., no major engine work in past. Engine runs great. Consumes 1qt/500mi. No smoke, I've tried to rev in a garage to see if it makes blue smoke and doesn't. Put front end on ramps, changed transmission fluid. Drove on the interstate the next day, BILLOWING blue smoke from exhaust for about 10 miles, then slowly went completely away. Engine never skipped a beat at 70 mph.

Any suggestions?

Have you looked at the block to try and see where it's wet?

I am assuming you have a puddle where you park it... ie the oil is not dissapearing out you tailpipe or into your coolant...

The most common leak is at the upper timming chain cover (front of the block under the dristributor) you should be able to see where the upper timing chain cover meets the lower cover and the block.

__________________
-Marty

1986 300E 220,000 miles+ transmission impossible
(Now waiting under a bridge in order to become one)

Reading your M103 duty cycle:
http://www.peachparts.com/shopforum/831799-post13.html
http://www.peachparts.com/shopforum/831807-post14.html

No wet spot on the floor, small amount leaks from the oil level sender (not via the O-ring). Otherwise no wet spots on the block.



Jim

I remember way back when MBDOC reported a valve guide upgrade for models after April 1988. Even if you have the better guides, with the mileage and age, you likely need a turn-key valve job to include new guides and valve stem seals.

__________________
Mike Murrell
1991 300-SEL - Model 126
M103 - SOHC
"Fräulein"

New valve seals is a relatively easy job that does not require taking off the head. About four hours of labor I think and insignificant cost for parts. It's worth a try although you probably will need a valve job before too long.

Valve Seals or those aftermarket Umbrella's over the guides to keep out excessive oil, try Redlkine Synthetic straight 30wt oil, they have a larger molecule than Dino oil and will not break down

__________________
Jerry

2004 SL500 Black 55K Miles
2002 s500 Black 90K Miles
1986 300E Gold 233K Miles
1966 Twin Cessna 320D
1989 Jeep Cherokee 233K Miles
1994 Ford Van E150 399K Miles