Sealant for chaincase

Information relating to the Matchless G9 or AJS Model 20 500cc twin
Oggers
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Sealant for chaincase

Post by Oggers »

Chaps

Quick Q

Boxing up the chaincase, bead of silicone applied on the mating halves, wellseal on the rubber seal. Thinking of melting some wax/tallow or something similar and pouring it inside the chaincase as a further seal for the bottom edge...

Thoughts welcome.
56G80S
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Re: Sealant for chaincase

Post by 56G80S »

There've been lots of discussion of this.

It'll still come out of the dynamo orifice!

Johnny B
Oggers
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Re: Sealant for chaincase

Post by Oggers »

Nope - an entirely unrelated issue.
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thornebt
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Re: Sealant for chaincase

Post by thornebt »

Oggers wrote:Chaps

Quick Q

Boxing up the chaincase, bead of silicone applied on the mating halves, wellseal on the rubber seal. Thinking of melting some wax/tallow or something similar and pouring it inside the chaincase as a further seal for the bottom edge...

Thoughts welcome.
I smeared a good thickness of tallow along the bottom half of the join of the chaincase, refitted the chaincase and then gently heated the join with a hot air stripper. I had to heat it gently as I had repainted it with POR15 paint and didn't want to spoil the finish or heat the rubber seal too much. The chaincase has never leaked since.

Cheers. Bruce.
Oggers
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Re: Sealant for chaincase

Post by Oggers »

Bruce

Yes - thinking of similar - but chaincase is already assembled. I'll have to drip it in through the clutch cover or some such.
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thornebt
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Re: Sealant for chaincase

Post by thornebt »

Oggers wrote:Bruce

Yes - thinking of similar - but chaincase is already assembled. I'll have to drip it in through the clutch cover or some such.
What you need is a little device with a pipe to feed the melted tallow through and one of those cameras that you connect to your smartphone (endoscope?) so you can see what you're doing. Or is that getting a bit high tech?

Cheers. Bruce.
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dave16mct
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Re: Sealant for chaincase

Post by dave16mct »

If you've put silicone on the chaincase halves you shouldn't need anything else. I can't understand why you didn't get the improved seal from the club and you wouldn't need to mess around with any of these.
Dave.
raffles
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Re: Sealant for chaincase

Post by raffles »

To right the new rubber from the club just does not leak
Tony
56G80S
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Re: Sealant for chaincase

Post by 56G80S »

Yes, I know that you were asking about the tin chaincase seal but after what you've already done, if done properly, that won't leak.

It is, however, not unusal to get some drips out of the point where the dynamo enters.

Others have pointed to the other solution - the seal from the Club instead of the standard "rubber band".

Johnny B
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dave16mct
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Re: Sealant for chaincase

Post by dave16mct »

Johnny, it won't leak from the dynamo hole because it's a twin and the dynamo is at the front of the engine.
Dave.
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