Greetings,

I was researching some oil leak threads, and read that overfilling the oil can cause leaks from odd places. Where would those places be?

Here's the deal, I just bought the car, and the original owner said her dealer told her the rear turbo was leaking oil. While at my local dealer, they said it was coming from one of the motor mount bolts that goes through the pan (dumb, dumb, DUMB design, BTW).

Anyway, I tend to believe the motor mount theory, but I thought I'd ask about the leaks from overfilling first. The car is just about a quarter of an inch overfull on the stick from the original owner. I'm just wondering if I should bother to drain some as a test, before I drain it all to re-seal the mount bolts (did I mention that was a dumb idea).

Cheers,

 

Before you go through all that trouble do this. Get under the car and clean off the rear turbo oil line area where it attaches to the rear housing really good. Drive the car for a few miles and get back under there and see if that is your leak? I would not be surprised if it were. Those little 10mm nuts have a tendency to back off and leak oil. That may not be your problem but I am thinking it's a good place to start. I don't see why high oil levels would bring out leaks that were previously not an issue.
Good luck

 

I would guess the motormount bolt goes through the top of the pan or near the top and if the pan is completely full thats when it would leak. Anyone else know any more about this. I just recently had my turbos changed and I still have the same leak I did with my old ones. I am constantly filling my oil due to this leak and i try to keep the levels pretty high because I am paranoid about running my car with too little oil. It would be ironic if that was what was causing my leak this whole time.

 

Interesting theory. I just found a decent picure of how the mounts attach, and see how an overfull oil pan could cause some problems. Of course, the bolts should be sealed anyway, since oil does slosh around, but as it is now, it leaks while just sitting in the garage. I'll try to get under there today, if I can get this thing up high enough to do any good. As stated, I need to find out for myself where the oil is coming from first.

Thanks,

 

Its ok to run a little low, so try running, say, between the F and L marks and see what happens. Just never let it go below the L mark and you're fine. Running too full can create extra blowby into the intake, so if you're getting oil dripping out of the y-pipe then that may be the cause. Never heard of oil dripping from the oil pan bolt, although a very common leak is from the oil pan seal itself, and obviously this can't be solved with running low oil. I've only heard of running low helping with blowby, although a tight set of turbos shouldn't have any significant amount of blowby even if the oil is F. If its past F, then drain some of it out! Or if you're lazy, just wait until it leaks out below the F mark, clean everything up, and see if it keeps leaking .

 

Ha! I've been hoping the overfull problem would solve itself, but it's not leaking fast enough It makes a real mess, but I guess a little oil goes a long way. Thanks for the comments.

 

I drained out some oil, until I was about a quarter of an inch below the full mark, then I took the car to a car wash to blast off all the oil from the subframe. When I got home, I still smelled oil, but didn't really see any leaking like it was before. I put it on the ramps, and took a good look with the bottom cover off, and found 3 places that looked like they were leaking some. One is the oil return line from the front turbo, but the bolts were not loose. Another was the rear turbo compressor section. There was just a bit of oil on bottom half of the housing. Finally, the right rear motor mount does appear to be the primary leak.

The good news is that my leak isn't nearly what it was since I drained some oil. I took it for a pretty serious drive this afternoon. When I got home, there was a smell of oil burning, but none has actually dripped on the plastic sheet that I keep under the car. This is a very good sign, and I'll see if it lasts. Before, the car leaked continuously, whether you drove it or not, so that makes me think it was something to do with a high oil level. Either way, the mount should be resealed, but now perhaps I can wait until I need to pull it for some other reason, rather than having to do it just to fix a leak.

Thanks to all for the comments.