Hey all,

Looking for some feedback on a oil leak situation. I tore down my R53 over the winter to replace the clutch and refresh most of the normal areas. When I began driving it again, I noticed small drips of oil on the garage floor. Under the car, the oil was dripping from the seam between the bell housing and the engine. I pulled the inspection panel for the flywheel and the inside was oily. Not good

I was hoping that maybe the oil pan gasket was leaking from the portion located inside the bell housing, so last week I loosened the bell housing bolts and re-torqued those 3 pan bolts. I cleaned everything really well. After two drives, oil dripping again from the same spots.

So, I believe it has to be the rear main. What are the chances of a brand new rear main leaking? This is not the first rear main replacement under by belt (first on a MINI) and I didn't have any issues (at least I thought) during this install. More importantly, if I'm going to drop the trans again to replace, I want to be sure the second replacement is done correctly before putting it all back together. Any tips or sure-fire way to know its 100% before reassembly and road test?

Thanks

 

Ok, well I spent a few hours this afternoon pulling the trans and see what is going on. As expected, the rear main was leaking. Oil was collecting around the bottom of the seal and I noticed an issue with the seal lip at the top of the seal. Got the seal out with minimum damage so o could determine what the problem was. The outside lip at the top looks and feels almost like it is dry rotted; missing chunks of rubber. The rest of the outer lip and seals feel and look fine. FYI - this is a Victor Reinz, installed in December. Has seen less than 500 miles.
What I don't understand is that I would think most of the oil retention ability comes from the inside seal that has the spring around it. That part looks undamaged. Also, the crank is smooth. No grooves or ridges.

Any input would be appreciated. Should I try another Victor?

 

Just wanted to close-out this thread in case anyone reads in the future. I installed a new (Fel-Pro) rear main, got the car back together and have driven it twice - so far no oil drips. I'll keep an eye on it but I think I'm good now.


New Fel-Pro Rear Main Installed

Still not entirely sure what the problem was, but I suspect the first replacement may have been old stock - rubber seamed almost dry rotted/brittle in some locations. I never took notice the first time around, but comparing the two seals this week made this evident. So check thoroughly before you install - taking it all apart again is a PITA. Although I was much faster this time around (7 hrs. start to finish) .

 

Looks like it may have been an original part made 15 or 20 years ago. I've had similar experiences on old NOS parts. I've learned to check the pliability of rubber parts because they tend to age harden sitting around idle for years.

 

Oh that really sucks you pulled the gearbox 2 more times because the (properly) installed seal was crap to begin with!

Thanks for the heads up.