I've noticed some peculiar goings-on with the oil level, as read on the dipstick of my 240D. I'm kind of paranoid about checking the oil level since having had an oil leak shortly after the engine swap. What I notice is that if I check it an hour after stopping the car, the oil level is almost perfect: a quarter inch below the full mark. If the car sits for a couple days, the oil level reads above the full mark by about a quarter inch.

I know that the two o-rings on the shaft that goes down the oil filter housing are supposed to seal the oil up in the housing; I changed those o-rings as part of the engine rebuild, but it seems like they still aren't doing the job they were intended to do. Or is this normal behavior? Should I adjust the amount of oil in the car so that the fluctuation stays between the too low and full marks on the dipstick?

Thanks for your opinion.

Kurt

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- '79 240D - engine swap complete! Engine broken in! 28-31 mpg! Lovin' the ride!
- '86 190D (W201-126) - 2.5 NA engine, 5 speed, cloth interior, manual climate controls, 33-34 mpg (sold to forum member).

I apologize if this is a stupid question, but is the car always parked in exactly the same spot when you check the level?

My driveway is irregular (slopes up to a slight crest, then more gently back down) and as I have three cars on the go they aren't always in the same spot... and I have found surprising differences on the dipstick according to (what seem to me small differences in) position.

In any case, all I can say is: I personally would not worry about what you describe. But my standards for what constitutes something requiring action do differ greatly from some others around here....

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Mac
2002 e320 4matic estate│1985 300d│1980 300td
Previous: 1979 & 1982 & 1983 300sd │ 1982 240d

“Let's take a drive into the middle of nowhere with a packet of Marlboro lights and talk about our lives.” ― Joseph Heller, Catch-22

Is it possible that the oil cooler is draining down over time? I don't know how the passages work on the oil cooler and whether or not the o-rings on the filter cover shaft would hold back the cooler oil or not. Does anyone else know?

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

I believe they do since I had noticed the same thing on my 240D until I changed the o-rings in the filter housing.

It takes a while for all the engine oil to drain back down into the oil pan. I believe the manuals say to check the oil about 10 minutes after the car has been shut off, not 3 days later. I think your first reading is what you want. I wouldn't be too worried.

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Best oil level for a Diesel engine
http://www.peachparts.com/shopforum/showthread.php?t=137517




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