Need help with Oil Leak

[R80rider]

Hi All and Happy Holidays!

Recently, my 1987 R80 has developed a small oil leak.  It appears to be coming from an area that I cannot identify with the Clymer's.  

Here is a photo of where I think the leak is originating:

http://picasaweb.google.com/lh/photo/_coj2TddbwPsRjFcgo79vA?feat=directlink

Update:  Maybe I should have been clearer - what the heck is in this area that could be leaking?

Any help you can provide with this will be greatly appreciated!

Bill

[nhmaf]

Can you tell whether it is transmission (gear) oil or motor oil ?   Chances are it is probably motor oil, and if it is coming down from that "shelf" like projection, above which is the "bell housing" for the clutch/flywheel housing, there is a reasonable chance that it is the rear main oil seal that is leaking.  The end of the crankshaft goes through it from the crankcase, and there is a cap bolted onto the shaft.  The seal fits around this cap, and the flywheel in the bell housing area is bolted to the cap.  As you can probably tell, this ends up requiring a fair amount of disassembly to get to.  So, before you dive in, it is good to try to logically deduce how likely it is that this is the problem.  IF you are reasonably handy with tools and go in a methodical way, you can do this work yourself if you don't have lots of $$ and an airhead-friendly shop nearby.   It is also a great project for those BMW "tech-days", if they have those around where you are.

How quickly/how much is it leaking ?   Have you noticed any issues that might be attributable to having oil on the clutch disks (slipping, engagement issues, strange noises) ?
Have you pulled the transmission on an airhead before ?

[montmil]

... Chances are it is probably motor oil, and if it is coming down from that "shelf" like projection, above which is the "bell housing" for the clutch/flywheel housing, there is a reasonable chance that it is the rear main oil seal that is leaking...

Mike is probably correct with his guesstimate regarding a worn oil seal.

As you really don't have an off-season for motorcycling in San Diego, you'll have to decide if:

1) I can live with the leak. Just check oil levels often;
2) I'm feeling confident that with some time, a shop manual and, with a bit of help from the R65 guys, I can fix this myownself...or;
3) There goes my economic stimulus check to the dealer.

Tool handy types can handle about 90% of whatever needs to be done on an airhead. It's doable.  [smiley=thumbup.gif]

Monte

[not-so-fast-ed]

My drip in that area turned out to be my clutch rod boot had deteriorated at the rear of the transmission.  Couldn't see it too well, but it was apparent when I pulled the transmission to lube the spline.

Engine oil smells far different than transmission oil.

My

 [smiley=2cents.gif]

Ed

[R80rider]

It is, without question motor oil.  My brother and I successfully rebuilt the clutch in my former 1979 R65, so a home job is possible but I think I will check with my independent BMW mechanic to see what he will charge for this before making a decision.  

It is only leaking a small amount as of now and has not affected the way the cycle runs.

Are there other things that should be addressed while this portion of the cycle is apart?

Thanks,

Bill

[Rob Valdez 79 R65]

Another source is the oil pump cover o-ring.  The screws need to be checked for tightness, anyway.  And yes, you will want to replace that o-ring along with the seal.

I'll say it now and make this your mantra:  BLOCK THE CRANK BEFORE YOU REMOVE THE FLYWHEEL

In case you hadn't heard it, before!


But it could always be your tranny input seal, but not as likely.


The spline lube is free!

[MrRiden]

Yes what Rob said Block the Crank and not with bungee cords and a board either. If you haven't heard of this procedure let the forum know.
rich
sparing details for now