silicone grease on primary rubber seal

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1216bandit

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I just recently had the clutch apart to clean the plates and am going to use atf in the primary. The previous owner used some gasket sealer before putting in the rubber gasket and I had a bugger of a time cleaning it out of the inner case where the rubber seal lives. I am thinking to use a silicone grease then install the seal as the atf wont dissolve it. Just want to check and make sure I'm doing the right thing! Would it be wise to put a little on the outer surface also after the seal is installed?
 
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Never used it on this application but have on plenty of others and can't see any issues with what you plan.
 
The silicone grease I have is a bit rubbish when warmed up. It basically turns to liquid and just drips off! Is there better silicone grease I should be trying ?

I just use yer normal regular grease on this seal personally, just a very thin smear.
 
Never gave heat a thought! Just did a quick search and found there is heat resistant grease. Will shop around and see what I can find. I would like to go that route if it avoids the grease getting soupy with heat

"Electrical utilities use silicone grease to lubricate separable elbows on lines that must endure high temperatures. Silicone greases generally have an operating temperature range of approximately −40 to 200 °C (−40 to 392 °F) with some high-temperature versions extending this range slightly"
 
If you use a new rubber seal just put it on and don't over tighten the primary case cover, when over tighten the outer case it distorts and it will leak, the centre nut I just tighten without to much pressure, doing it this way my primary hasn't leaked for over 40 years even running ATF oil, never any red oil drips under my bike.

Ashley
 
I use grease on paper gaskets with good effect. I also use a tube of vacuum grease in sealing applications and it works quite well.
 
Fast Eddie said:
The silicone grease I have is a bit rubbish when warmed up. It basically turns to liquid and just drips off! Is there better silicone grease I should be trying ?

I just use yer normal regular grease on this seal personally, just a very thin smear.
Click to expand...
The permatex I bought tonight is good for up to 550f.
 
MexicoMike said:
"even running ATF oil, never any red oil drips under my bike."

You sure there's oil in there? ;)
Click to expand...
Well it keeps running and the triplex chain is nice and lubed, my Norton has always been oil tight.

Always said my bike is a freak, see patting it on the tank and thank it for a great day out and getting me home safe works.
 
Important to first shim the support stud for the outer chaincase cover so that no flex or warpage can occur , when snugging down the nut . Dry assemble this first .
More important than type of grease . The rubber seal band should be soft and pliable with the casting mark line placed upwards center , to help prevent leakages , grease the rubber band into a clean cover slot .
 

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