Trying to track down a small oil leak on passenger side 1993 850

93ForMe · Post by **93ForMe** » 03 Dec 2020, 17:00

I've been noticing a small oil leak that is originating on the passenger side of my 1993 850. When I drive it and park it overnight there will be a small patch of oil on the ground ranging in size between the size of a quarter to the size of a silver dollar. If I run it for 10 minutes or so and look for oil actively dripping, I do not see any. I removed the timing cover and looked from the top at the cam seals and didn't see any oil. I couldn't really see anything wet from the top at all. From the bottom, through the passenger side wheel well, the dripping oil is quite clear:

: Oil Leak

I don't have any experience with leaks from this section of the car, so I would love some advice. Is it possible that plate below the crankshaft pulley in the photo could be the culprit? What is that plate? If not, I am guessing that it might be the crankshaft seal or the oil pump seal?

Thanks!

hipcheck · Post by **hipcheck** » 03 Dec 2020, 18:45

I’m currently looking at an oil leak right there in the same area. I think my culprit was a dipstick o-ring. In that area there are 2oil lines that go to your radiator (I assume, my 1997 does) and they come out of a metal module. I cleaned my area up really good and will monitor the situation.

The things to check there from what I observed tonight: dipstick O-ring, oil pan gasket, oil cooler lines (rubber to metal section failing) connection to the block (assume there are o-rings or seal of some sorts)

Good luck

Steve

Post by **FLXC90** » 03 Dec 2020, 19:14

That plate is where the oil cooler thermostat and lines go on the turbo models. Yours is merely a sealing plate. It can warp, or the seal may go bad. +1 on hipcheck's idea for the dipstick tube. on the less hopeful side, it could be the front main seal. (pulley and gear removal, reseal, reinstall ,not as bad as a rear main seal, but still involved. clean teh area with brake cleaner and a rag, and determine whether the oil is dripping down, or whipping up, then dripping.

93ForMe · Post by **93ForMe** » 03 Dec 2020, 20:14

Thanks to both of you for the advice! I did replace my dipstick and dipstick tube o-rings when I did my PCV system this past summer, so hopefully it is not leaking from there. I will check the other locations mentioned after I give it a good cleaning so that I can look for fresh drips without oil covering everything.

Thanks again

Richard99 · Post by **Richard99** » 03 Dec 2020, 23:18

I would guess that your leak is due to a failing crank seal. It is a common issue.

Eric

93ForMe · Post by **93ForMe** » 04 Dec 2020, 16:32

Okay, I tried to clean up the area as best as I could and started it up and ran it for a bit. I saw a very small seep of oil start from what I think is the mating between the oil pump and the motor?

I am thinking that the oil leak is originating from behind the oil pump. Perhaps the oil pump o-ring has gone bad?

I did check on the crankcase pressure with the glove test and I do have good negative pressure, so I shouldn't be blowing seals, hopefully.

From this picture does this sound like a reasonable guess?