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1992 Mercedes-Benz SL-Class - Is there damage?

I have a 1992 500sl 110,000 miles , car has been meticulously maintained oil & filter changed 2 months ago then I noticed my oil pressure was dropping, car ran fine ,then one morning I started it & it sounded like a diesel with no oil pressure at all nothing not even a slight movement on the oil pressure gauge , I immediately shut it off . what are my chances that there is damage done internally , I did not hear any knocking just rattling & tapping noises the motor did not quit on its own , only ran for a few seconds. I am going to drop the oil pan & replace the pump next week , hopefully no damage occurred .

90% chance there is no damage… there is a little extra wear from that little dry run but should be OK.

Wish you luck. Make sure the oil pump IS the problem. I don’t know where the pressure relief is on this engine but it sounds like the spring might have failed. Be sure and check it when everything is apart. You wouldn’t want to do all that work and find you missed the real cause.

Good Luck!

1 Like

Was your oil low? How low? I’d be surprised if the oil pump was the problem, why do you think it is?

This is not Benz-specific advice . . .

The root cause for low engine oil pressure is usually not the pump

the “car ran fine” part makes me wonder if you continued driving the car for some time, until that morning when it had no oil pressure and the engine was noisey . . . ?!

6 yrs ago my north star lost oil prime at store. No oil pressure warning message. Lifter rattle. Grr. Had to tow it. Easy trick was overfill by 4-5 qts and crank motor. Oil pump will prime. I sort of knew of issue but it didn’t click. Cost me a tow.