Leaking oil cooler? Best fix?
 

I noticed the other day that I had a spot of oil on the floor under my mini. I put it up on ramps, and took and look at it. As far as I can tell, it's coming from somewhere around the oil cooler area.....but I'm not 100% positive. I cleaned everything up, wiped it all off and thought I would be able to see where it's coming from the next day. Well, this morning I pulled the car out of the garage and not it's left an even bigger spot...around a 2" round puddle of oil.

Are the oil cooler assemblies that are attached to the oil filter housing prone to leaking? If so...is there a seal that needs to be replaced, or does the entire cooler need to be replaced?

Anything else in that area that could be leaking? It's not the filter.....

Thanks!

There are two gaskets, item #6 (inlet and outlet) and one or both could be bad.
http://www.realoem.com/bmw/showparts...95&hg=11&fg=30

The heat exchanger or oil cooler has 2 replaceable seals. Trick used to seat em properly still prior to buttoning up has been to apply a thin dab of gasket-friendly grease as temporary glue.
It's not a difficult DIY....or, you may replace the heat exchanger or upgrade to an aftermarket 1.

Just throwing it out there...
Was the oil changed recently? Could the filter gasket not be seated properly?

The heat exchanger seals do fail over time.

Is it possible that the bolts could have just worked loose...and just need tightened? Or 99% of the time it's the seals failing?

Those were 1st I checked. Still wept. New seals stopped it.

Is there anything special about those two o-rings?.....or can I just match them up to some metric o-rings I can get from the hardware store?

Nope, get OE. If I recall right, 1 is straight edged, not rounded. They're cheap off Pelican, ECS, WMW....no reason why you'd take some metric equivalent.

Thanks for the info guys. I just ordered a set of seals off of WMW. :thumbsup:

https://www.northamericanmotoring.co...this-part.html

Here is the parts and the diagram and install.

http://www.realoem.com/bmw/diagrams/c/d/157.png

I had this problem about one year ago. I replaced the gaskets the first time using the proper torque settings, I still had a leak and the only thing that fixed the problem was replacing the entire unit.

Could be number 7 in the diagram ECS posted. Both of my MINI's leaked from that gasket.

Sent from my Droid Mini using NAMotoring

Well, hopefully I can see where it's leaking from when I dig into it tomorrow. I thought about ordering gasket #7, but I didn't. I guess I can always use some RTV or liquid gasket on it to seal it up if it's leaking from that #7 seal.

I'm not sure I'd use RTV or liquid gasket for this specific location but to each their own.

Sent from my Droid Mini using NAMotoring

Did you find the exact leak yet ?

Actually, when I started digging into it this weekend to fix the leaking oil cooler.....I discovered that the spots in my garage weren't from the leaking cooler, it was from all of the oil/grease that got thrown out of the cracked inner CV boot on the passenger side. That stuff is a sticky mess....it took me longer to clean it all up than it did to take the CV shaft apart and get to the cracked boot.

As soon as the new boot shows up, I'll be able to get it all back together...clean everything up, and then run it for a while and make sure the drips in the garage have stopped.

Yeah, CV grease splatter is indeed messy. I ran my cracked 1 wrapped in bandaged & tied garbage bag for a ehile til I finally found time to fix it. Pelican has some good hobo replacement boots.

My passenger side inner boot is torn. Any recommendations on whether to replace the whole shaft or just the boot? I should have done it along with the clutch job but didn't want to wait even longer for more parts. I'm at 138K miles FYI.

Sent from my Droid Mini using NAMotoring

Changing the boot isn't difficult. Unless you suspect wear, I'd just fit a new boot in. Clean & regrease the joint thoroughly.

Thanks for the feedback Minsanity

Sent from my Droid Mini using NAMotoring

****UPDATE****

Well, I found the torn CV boot....fixed it, and then I was still getting the oil drips on the garage floor. The drips seemed to be coming from the bottom of the oil cooler. So I replaced the two o-rings on the faceplate of the cooler...and I thought all was good. Then after a week with no leaks.....I'm starting to get little drips on the garage floor in the same spot.

What else is there is that general area (oil cooler area) that is pretty common to leak? I checked the valve cover gasket, oil pan gasket, and checked to make sure the oil filter housing was tight.....all checked out fine.

Any other ideas? I hate leaks!!

The oil filter housing gasket to the block is a common leak. The gasket is $8

Is that the gasket that separates the oil from the coolant?

No it is not -- its number 7 in this image:
http://www.realoem.com/bmw/showparts...95&hg=11&fg=30

Sold by ECS tuning here:
http://www.ecstuning.com/Mini-2006-C...Seals/ES23998/