My 2008 Cooper S with 144k miles has had the oil pan gasket changed thrice by the dealer including a new oil pan and it continues to leak. I thought there was no way in hell it could still be leaking. I thought the leak was the crankshaft (main) seal, or maybe the valve cover (changed by dealer once) or the vacuum pump (definitely leaking), or the oil filter and cooler housing (both changed by dealer and still leaking) or the crank position sensor. I changed all of those again and still the pan was wet around its entire periphery.

So today I dropped the old pan and installed a Fel-Pro OS 30820 oil pan gasket.



The pan is easy to remove. Its sixteen 8 mm bolts. You'll need a 1/4 drive and extensions, a very small torque wrench. 1/4! Don't use a 3/8 inch drive torque wrench! You'll over tighten the bolts, or break them, or crack the engine block.

You will need to disconnect the exhaust from the downpipe back, and remove the exhaust from the 2 rubber hangers so you can more easily push it to the left and right in order to access the bolts directly above the exhaust flex pipe. You can leave the muffler on its hangers.

You will need to drain the engine oil. (reuse if you wish, I did)

You will also need an 8mm boxed wrench to get the one 8mm bolt directly above the downpipe's 90 degree bend. I have 2-3 different 8mm box and ratcheting wrenches and they all came in handy for the one bolt just above the downpipe. This is because their is barely enough room to get a 1/4 inch ratchet and 8 mm socket in that space. You could remove the downpipe...but sheez....that would be way too much extra work for one bolt. You also wont be able to torque this one bolt to spec, for the same reason, unless you use a crow's foot. I just hand tightened it.

My pan was very securely glued to the block despite the leaking. I had to smack it from front and rear many times with a rubber mallet to get it to break lose. Don't pry on the seam with anything sharp. You don't want to scratch the mating surfaces. If you have a plastic tool for clips and fasteners, use that to help pry the pan off the engine block.






You then need to clean the mating surfaces thoroughly in preparation for the new gasket. Both the pan and the engine block. Its gotta be totally clean of any residual black RTV.

I used 3M Scotch-Brite Roloc Bristle Disc 07528 (Ceramic Aluminum Oxide, 2" Diameter, 120 Grit) with an air die grinder for the pan and some cloths for the small bits stuck to the engine. I suppose the fact that the engine had almost no RTV stuck to it is a bad sign.

Make sure and clean inside the oil pan after you've cleaned off the old RTV so you don't contaminate your engine oil.

Note that the FELPRO gasket fits in only one orientation, both up and down and left to right. Its partially metallic.

Torque spec for the oil pan bolts is 12 nm. Install BY HAND first so you don't cross-thread any bolts and then torque in a crisscross pattern.

DON'T USE A 3/8ths inch torque wrench. Use a 1/4 torque wrench. Its only 12nm. (Torque wrenches are least accurate at their lowest setting and a 3/8 is way too big for this job anyhow.)

***Use medium thread locker on the bolts (such as Loctite blue).***

Be careful not to strip the bolt heads. I stripped 2 of mine ever so slightly and had to use some slightly smaller English unit 12-point sockets to get them off. They strip easily if your socket is not on straight.












Now just add back the engine oil you drained.

I'll let you know how the gasket holds up.

 

Nice Job, Lex. My Mini still has the original gasket, probably should be changed. Interested to hear how the Fel-Pro gasket holds up.

 

I sure wil bro.

I have Koni FSDs in my mini as well.

 

Nice diy.

 

UPDATE:

The car went through a tank of gas (350 miles?) and multiple hot/cold cycles since installation of the FEL-PRO gasket.

I checked the oil pan gasket today...its bone dry. Its never been dry before. Its always been wet at the intersection of the pan and block. It had been leaking continuously despite three tries by 2 dealers.

Could this be the final solution?! I hope so.

I'll check intermittently and keep ya posted.

 

Wholesaler closeout at ROCKAUTO for this gasket: http://www.rockauto.com/RSS/vehiclef...l=en&html=true

 

Update. Its been 6 months or so, not sure how many miles, but not more than a few thousand since I installed the Fel-Pro oil pan gasket.

I checked the engine oil today and it was real low (I hate trying to decipher the dipstick, but Im guessing 2 quarts) so of course I immediately went to look for leaks and found the seam of the oil pan was wet. The other usual suspect was dry (main/crankshaft seal) I immediately got out the 1/4 torque wrench and found that every last bolt was totally loose. No wonder its leaking...a few more months and the SOB would have fallen the F off the car.

I took each bolt out one by one, brushed the threads clean with a small metal brush and painted with Loctite blue and reinstalled with torque wrench (12nm or 8.8 foot pounds). I used Loctite last time but clearly not enough.

Check those bolts guys and Loctite them generously. If they loosen again Im gonna need to buy some expensive locking bolts, assuming they exist in this size and pitch.

 

Update. The oil pan started leaking again. The rear of the pan's seam was wet, so clearly the Fel-Pro gasket couldn't handle the changing gap of the aluminum block and steel oil pan OR I didn't follow the torque sequence carefully enough. My oil pan is new relative to the car.

So I took it apart again and reused the same old Felpro gasket but loaded both sides with Permatex UltraBlack to see if the combination of liquid gasket and hard gasket could handle the changing gap.



Here is what it looked like when I pulled it down:










This car is truly an oil strainer. Lets hope this works.

 

It probably lost its seal when the pan got loose, and that took a while to become evident.

The most common problem with oil pan bolts is people getting them too tight and distorting the pan or breaking the seal of the gasket material. You avoided this, but IMO the bolts working loose broke the seal.

I think you'd be wise to replace the gasket with a similar one, use a lot more Loctite on the bolts, and re-torque just as carefully as you did the first time. I think the pan would not have leaked if the bolts hadn't worked loose, so the fix is to avoid that.

Don't over-tighten the bolts.

 

Good point ColoCoug. I definitely lost the seal when the bolts backed out.

I happened to have the ultra black RTV handy but not another Felpro gasket so I went with the liquid gasket.

I always torque to spec with an inch pound torque wrench.

Fingers crossed. If not Ill order another Felpro and try again with oodles of loctite blue.

 

Thanks for the update.

Seems like only the liquid sealant holds in the long run ?

 

You have very poor reading comprehension skills my bro.

 

Alright boys round #3 is complete. I used another new Fel-Pro hard gasket. I chased all the threads with a tap (M6 x 1.00 tap in case your wondering) to clean the threads and remove old Loctite Blue, then I blew out the holes with brake cleaner (yummm tastes great) to remove grease, metal bits and old Loctite from the end of the bolt hole. Make sure you look into the holes to assure that they are 100% debris free or you wont get the bolt in far enough to seal the pan.

You can buy the tap at Home Depot (way cheaper to get master set of taps and dies. They come in handy when **** like this goes down).

In retrospect I should have just used the RTV black without the used/crushed Felpro gasket. I bet it would have held a seal. Reason I say that is because the RTV adhered well to the aluminum engine and the oil pan. At least for the short time it was on there. The leak seemed to be between the old felpro gasket and the RTV. I swear I took some pics but I cannot find them.

But I digress....back to the thread chasin...

Put some tape on the tap so you know how far to chase the threads.



Upon install, unfortunately for me, one of the bolts broke in the engine block (yes I was using an inch pounds torque wrench) and another bolt stripped the aluminum threads in the engine block so I had to use a Helicoil M6 x 1.00 on both holes. Not a good feeling drilling into the aluminum engine block but the helicoils worked as advertised. Another brand of thread repair kits is Time-Sert. Ive used those multiple times. They are really really good, tricker to use, much stronger, but 3x the price ($23 vs $65) and not really worth the extra cost for low torque situations like this, in my opinion.

For the helicoil kit you'll need a 1/4 metal drill but (extra long if you do it with the pan in place, which was my case because I didn't want to release tension on the new Felpro gasket and have to buy yet another gasket. Well let me clarify...the bolts holes I had to drill out were on the far left and right of the pan and either the pan or the downpipe were in the way hence I needed an extra long drill bit.







IF and ONLY IF you do this job with with the pan in place, you'll need a 1/4 ratchet extension and some tiny sockets for the back of the tap wrench or some tap-specific sockets (https://www.amazon.com/Lisle-LI70500...ds=tap+sockets) because the tap wrench that's typically used to hold the tap is too short and or too wide to reach the extreme left and right bolts on our oil pan when the pain is still in place.

Lots of improvisation to get those holes tapped in that recessed space. Thw worst being the end of the downpipe which is directly, exactly 100% vertically below the hole I was needing to tap.





Tip: Do not put two helicoils inside the hole to fill its entire length. You dont need more than one per hole and 2 pushed up against each may cause the threads to misalign and then youll be stripping the end of the bolt as you force it into the deepest helicoil which is out of sink with the shallower helicoil.

I drove the car maybe 15 miles and the pan seal was dry. I hope the bolts stay firm. If not, I have one last trick.

 

Sorry if I missed something, I though you said the paper gasket did not hold so you used paper and sealant: " The oil pan started leaking again. The rear of the pan's seam was wet, so clearly the Fel-Pro gasket couldn't handle " .

 

I know you guys sell the BMW approved liquid gasket. But Mini used that 3 times on this car (last owner) and it never worked (including a new oil pan). Was it bad install technique on the part of mini? Maybe.

 

I used RTV only when I dropped the pan on our past 2010. We traded it in 5 months later and it was not leaking any oil. You must make sure you clean both services so no oil is present and let the RTV set before installing the oil pan.

 

Thats good info. The Permatex RTV seems to stick to the aluminum block. The Mini/BMW specific didnt, in my case; I pulled the oil pan and the engine block had zero liquid Mini gasket on it. Then again maybe the Mini mechanic didn't clean the block before resealing the pan for the 3rd time...

 

I need to replace thev oil pan gasket on my R55 but am not sure what would be the best way to go about it now. Not sure if I should try using a gasket paired with RTV, RTV only, or the 5970 Loctite only... I guess the cheapest option to try first would ve using RTV only and seeing how it holds up.

 

I bought the big sealant tube from pepboys and been using it on the minis when i rebuild the engines. The trick is that after you apply the sealant, you need to let it set for at least a day before you add the oil and start the car.

 

Good point. and that's why the hard gasket from FELPRO is nice. No curing period.

Whatever option you chose, make sure you clean out the threads of any oil with some brake cleaner (wear glasses) and use some Loctite Blue/Medium or equivalent.

Every time I've pulled my pan after using RTV, whether applied by me or the dealer, it had never adhered to the bottom of the block. It had to be scrapped off the pan however. Is this be design? I dont know.

 

i always scrape it and make sure it is dry. I can feel it tacky on both the oil pan and the engine block. with the right sequence and 10NM torque, it turns out good.

I tried the felpro gasket before and it was wet. it felt like the fibers of it were sucking the oil out (osmosis). maybe that is why this gasket is not a prescribed by Mini, no?

 

Really? Mine hasnt been wet since I installed the FELPRO.

Ill just say this. Mini changed the oil pan gasket 3 times with the BMW RTV. THREE. They also put on a new pan. And it still leaked.

You got the technique Mr.

 

...Mini wants you back in their shop, I dont

Either case might be fine, it depends on how clean the surface is and the torques sequence, i guess

 

What you don't like me Mr.?!

I'm sure they both work but I think the FELPRO hard gasket is more forgiving and easier for the rushed mechanic.

It was the last owner went through that nightmare with the dealer. I dont patronize dealerships.

 

I couldnt agree more