Attached is a picture of the bottom of the manual transmission in my 14 CMS4. I noticed this oil a few weeks ago, shortly after buying it and cleaned area up really good. Noticed today that there is a small amount of oil at A, where halves/shells/elements of clutch housing meet. Though I was unsure previously, the two holes at B do not seem to be where oil is coming from. Oil does not appear to be running down back side of transmission--checked with mirror. I have not jacked car up and crawled under yet due to lack of time. It doesn't appear that this would be the logical path of oil spilled from changing the oil filter, but I will admit I am new to Minis.

Car recently had a new clutch installed by prior owner at dealership and I am hoping that a leaking rear main seal was not ignored. However, it seems that if rear main seal was leaking, it would leak out the two vent holes before it seeped out between shell halves. Clutch seems to be working well. Sorry about crappy pic. Hoping the collective NAM wisdom can guide me.

Let 'er rip.

 

Just mopped oil up again. Definitely less oil than a week ago. Also checked holes B with q-tip and they don't seem to have any oil coming from them. Just along the seam.

 

I had the same problem and it was a leaking oil housing gasket. It'll run down and look like a leaking rear seal.

 

That was on an N18 engine as well?

 

Sorry, that was an N14.

 

Check your Oil Housing Gasket
Just replace Mine @ 75k +/-
Also Check your Oil Control Valve As it can seep up into the wiring harness and cause some major issues.
Ive replaced Both on my 2011 r60 N18 Engine.
Best Of Luck Update your findings!
\m/


PM

 

I will look at oil housing gasket and oil control valve, though I really don't see any creek/stream/trickle running down outside of bell housing at all.

I dusted area with baby powder and took another pic to show things better. You can't see the rear vent hole, but it looks wetter. Front vent hole is obviously dry. "Eye" spots don't connect to anything and must be where I rubbed powder off. Gotta pull that exhaust bracket off, so I can look directly at rear vent sometime...

 

Interesting

https://www.northamericanmotoring.co...il-line-3.html