Is this a normal oil leak?

speirmoor · Aug 19, 2010

[video]http://www.youtube.com/watch?v=Y-dRVxBiMYQ[/video]
Cleaning up the bike the other night and going for a short run afterwards I noticed smoke emerging from the Exhaust crossover.It looked like the left
rocker cover gasket was leaking drops of oil on to it.Not so worried I replaced the gasket with a new one and the problem only temporarily went away.After cleaning everything up I restarted the bike and after another spin I still see oil like these pictures.the smoke has since gone away.

Maybe I need to tighten up the rocker cover more or could it be coming out of the exhaust lock ring nut.

JimC · Aug 19, 2010

Most stock valve cover gaskets are larger, on the inside, than the cover. This creates a dam for oil to accumulate. Trimming the gasket to size will help.

britbike220 · Aug 19, 2010

Mine does the same thing. Never thought of cutting back the gaskets, nice tip Jim.

speirmoor · Aug 19, 2010

Thanks Jim I didnt think of that.

JimC · Aug 19, 2010

speirmoor said:
Thanks Jim I didnt think of that.

In as much as I'd like to take the credit, the fix was passed on to me by Bob Raber.

cash · Aug 19, 2010

Try sealing the studs into the head, use stud lock or a thread sealant.
Cash

lrutt · Aug 19, 2010

I had the same leak. First try lapping the cover to make sure it's flat. Mine wasn't. Also, the stud had built up a little bridge of AL at it's base which I cleaned back. I also then used a gasket sealer on the cover and now am totally leak free there. That means new gaskets etc. every time I do a valve adjust but that's a small price to pay for no oil leak IMO.

pete.v · Aug 19, 2010

Check the oil lines into the head. Torque as needed. If the are the plastic type of old, they will crack and slit ever so slightly generally right at the fitting. They will appear to be fine at idle yet blow oil when running down the road. The area where you show oil is where it will collect from leaky lines. It can seem so mysterious as to where the hell the smoking oil is coming from.

My lesson was that I pulled the head only to discover the line later after re-assembly. The fortunate part was that i discovered a bad top piston ring. Unrelated,but fortunate just the same. Of course the fortunate part was the discovery not the broken ring itself..

speirmoor · Aug 19, 2010

Thanks Pvisseriii I didnt even think they could be at fault.
Mmm lots to check out on next startup.

Hobot · Aug 20, 2010

I've read of a number of reports in 850's that the head casting itself its porous. They use some special paint to seal. IIRC oil shows up like a rocker cover leak or into engine to smoke. LIkely not leak your case but entirely possible.
I had best luck sealing oil feeds with Al instead of cherry red heated Copper washers. A lot of vendors know this so supply Al washers.

bmwbob · Aug 21, 2010

I leave the gaskets dry, but if you look you'll see the studs cut into the head and oil wicks up threads! You have to put a dollop of RTV under each nut! :wink:

Is this a normal oil leak?

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