1992 300sd PROBLEM? HELP - PeachParts Mercedes-Benz Forum

#1 03-23-2004, 12:14 AM

Hello all, Well I bought this car 1 week ago 150kmiles and it has had one owner all service records. Well problem is the car uses lots of oil 2qt. every 800miles.
Bad turbo? Car is slow but Im not sure how fast its supposed to be. Dont overheat. Little black smoke on take off. i dont think it leaks oil. Great gas milage 500 miles to a tank city driving.
Starts right up. How do I know if I have a bad turbo, oh I never hear it spool up is it supposed to? My last car was a 1991 toyota
supra turbo. I hope im not to screwed. Should have ask question first hey! Thanks in advance. Elton I hope I did not F#ck my self.

Marcb · #2 03-23-2004, 02:01 AM

I hate to think about it, but it sounds to me like you may have the infamous 3.5L OM603.97x engine problem with the connecting rods. That oil consumption seems very severe and I suppose it could be a turbo seal problem, but I bet you have a bent rod.

Just IMHO.

slowmoe · #3 03-23-2004, 06:57 AM

Welcome to the board!! Much has been discussed regarding your car and the issues surrounding its engine. Therefore, I would first recommend that you do a search. Be sure to include your 3.5L engine displacement.

Do you have any records on the car?

Did you have a compression check done prior to purchase?

#4 03-23-2004, 03:53 PM

I have all records for the car. I was looking over them last night
and the car started using up oil at about 137,000 miles, now it has 150,000. I did not have a compression test prior to purchase.
I thought all benz diesels were "bullet-proof". I had another question what does the turbo feel like when it kicks in? My car really never boosts@ 2000rpm it is very slow takes a long time to get to 70mph thats why I think the turbo is bad. Also how quite
is this diesel supposed to run@ idle mine makes noise but all diesels run loud dont they?

joe p · #5 03-23-2004, 06:12 PM

Hows the idle? If its pretty smooth with no skipping and there is no blue smoke at idle I'd pop the intake x-over pipe and look for a wet intake. Vacum lines will also cause these not to boost as will stuck ADLA's, plugged filters (altho most will launch and fall flat on their face) and I've run across a few that the base pump timing was in the 20 deg zone and just ran like crap. Just for grins take the line from the intake nipple (right over the shut off valve on the pump) and run it straight to the ALDA which is the sorta square looking thing with the 2 lines hooked to it. these lines will be clamped as they are boost not vacum.

Joe