R65 Leaky Oil Filter Cover

[YOCKYRIDES]

My 83 R65 has had a strange problem where the oil filter cap leaks at times. The mating surfaces are perfectly clean, the gasket, o-ring and spacer ring are properly positioned. The cap has been replaced twice and isn't warped. The 3 mounting bolts are fine, no stripped threads. The screw holes are fine, everything torques up properly.

A double gasket has worked but that can't be the real solution.

Any ideas on root cause and solution?

 

[flash412]

Any ideas on root cause and solution?

Put the metal shim in first, THEN put a new, big soft-rubber o-ring in, then put the cover on with a new gasket. That big o-ring is NOT a typical o-ring. It should be a lot softer, and is probably white in color.

 

[lkchris]

Throw the paper gasket away.

All it does is reduce pressure on the white o-ring, which is the ONLY thing that seals the system. Using more than one paper gasket only makes it worse.

Yes, the purpose of the metal "shim" is to protect the o-ring from the sharp edge of the filter canister.

If your bike is one of the very latest versions, it could have a folded-over edge to the filter canister. In that case, even the metal shim is not required. This is not likely the case for the R65, unless it's one of the post-'84 models with the big frame.

The center "peg" of the filter cover inserts into the filter, and your filter should have a rubber ring on each end.

 

[The_Veg]

I'll second the motion for tossing the gasket. And that big white O-ring is *CRITICAL* to the engine. It is often referred to as 'the $2000 O-ring' because if it fails to seal, that's about how much it will cost to repair the engine. Probably much more nowadays. If the O-ring fails to seal, you lose oil pressure.
Some folks change them every other filter change or less, some change them with every filter. I do the latter just as cheap insurance. If you buy the oil change kit rather than just the filter it comes with an O-ring. I keep a few healthy-looking used O-rings on hand just in case. They do tend to get kind of a squarish cross-section after a while in use though.

 

[YOCKYRIDES]

I've done nearly 100 oil changes on this bike since I purchased it new and I have not needed an engine job so something must be right after 149,000 miles. My dealer did a cylinder leak test and measured less than 5% loss on each side.

I'm not sure I buy the notion that the paper gasket is the problem. I've always purchased the filter kit. Early on it was the single cartridge but then I discovered the jointed filter cartridge and prefer it because it is easier to handle. I always change all of the components including the metal shim and the o-ring. Always rub a bit of oil over the rubber parts to lubricate before putting them in place.

 

[lkchris]

I'm not sure I buy the notion that the paper gasket is the problem.

Start your engine at zero degrees with 20W-50 and say that!

I can show you an official factory drawing from the service manual showing paper gasket omitted. It's for /6 and earlier models only, and obviously has to be included in the kit.

 

[YOCKYRIDES]

I've done my share of severe cold weather riding but I run 10W40 in the winter. Usually switch over in mid-November.