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Rear main seal leaking? (NOT)

mikewillison

New member
1998 R1100GS (52,000 km)

I replaced the rear main seal 20,000 km's & 4 years ago.
But I always had some oil seepage between the cases on the right hand side.
So in I go again.
The gearbox input seal is dry.
The rear main seal looks good. But!
The bolt (red circle) comes right through the casing.
The oil is radiating out from around it.
I suspect that engine oil is following the threads right into the clutch housing.
My plan is to JB weld over it.
Anyone seen this before?
Any other thoughts on repair?
Thanks
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Welcome Mike!

From my experience, there is nothing that will keep oil from leaking out of there if patched from the outside.
I think you need to give the oil a way to get all the way out, like a hole in the bottom of the casing.
 
This has been discussed before.
Pull the bolt, wash threads and bolt thoroughly and blow dry.
Coat bolt with a quality sealant and re install.

I have had success with JB weld but the surface has to be 100% free of any trace oil. (solvent, air acetone) Reinforcing the JB with a little patch of fibreglass cloth helps as well. Allow 1 application to cure and repeat.
Years ago I had a Yamaha with a porous casting right by the oil gallery. The above fix lets me tell you that it does work
 
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Thanks for the replies.
Putting sealant on the threads would be the best for sure.
I assume this would mean removing the cylinder.
However since I am already in there I will try the JB weld.
I have had very good success with it before.
Tried searching for previous discussions on this but no luck.
 
Thanks for the replies.
Putting sealant on the threads would be the best for sure.
I assume this would mean removing the cylinder.
However since I am already in there I will try the JB weld.
I have had very good success with it before.
Tried searching for previous discussions on this but no luck.

I saw this issue discussed here I think about a year ago or so.

A buddy of mine had a low speed, low-side which wore through the clutch cover on his Honda twin. Being a fair distance from civilization, we leaned the bike over towards its opposite side to get the oil away from the clutch, thoroughly cleaned the outside and patched the small hole with JB Weld. Stayed dry for 4 years until he sold it. GSAddict has a much better and more permanent solution but best 'o luck with your repair.
 
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