Leaking primary cases!

Information relating to the Matchless G80 or AJS Model 18 500cc Heavyweight.
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Rob Harknett
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Re: Leaking primary cases!

Post by Rob Harknett »

I note for tin primary chain case, the words " oil tight " are used. It should be " oil & water tight " So you will need to check your oil after riding in wet weather to make sure not too much water has got in. The oil will become frothy and need changing. If the chain case seeps a little oil, any water will drain out OK.
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dave16mct
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Re: Leaking primary cases!

Post by dave16mct »

Rob I can't agree with that. If you keep the oil in, you'll keep the water out. Unless you're garage gets flooded out (15" deep in my case), then you'll need to drain it out.
Dave.
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Rob Harknett
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Re: Leaking primary cases!

Post by Rob Harknett »

Had it happen a few times over the last 60 + years Dave. Mainly in 50's / 60's roads I used to get to work often flooded that 15" or more. Not happend much during more recent ride for pleasure years. Last time was riding country lanes full of potholes with muddy water. If only a small amount of water has got in during rain, I have noticed water seeping out soon after putting the bike back in the garage.
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clive
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Re: Leaking primary cases!

Post by clive »

Rob Harknett wrote:... If the chain case seeps a little oil, any water will drain out OK.
Thanks Rob I can stop trying as of course I want to let the water out.....just wish the paving slabs at the front did not look such a mess.
clive
if it ain't broke don't fix
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Rob Harknett
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Re: Leaking primary cases!

Post by Rob Harknett »

Oil will only show up if you clean the paving slabs Clive. Let them all get weathered, perhaps even grow some Moss so you have a rustic country garden.
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Taid
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Re: Leaking primary cases!

Post by Taid »

dave16mct wrote:That hexagonal bar is the spacer/nut. You will need to add a washer or 2 to make room for the new seal to fit. It will be about an inch too long so cut it to length and put the joint at the top. Glue the ends if you like, I don't bother. Assemble carefully and most important, don't put too much oil in. It only needs just enough to barely touch the bottom of the chain.
Dave.

Thank you D.

tomorrow's job .. find some washers and have another go .. hopefully go for a short spin over the weekend ..

but just wondering, fit the seal and tighten up, then put the band round, or just lightly nip up on seal, put the band on completely and then tighten up the casing halves?

Thanks again

Taid
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Now sold ... 1956 AJS 16MS Bitsa .. HSU 414 .. rebuilt/re-registered 1987
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dave16mct
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Re: Leaking primary cases!

Post by dave16mct »

Centre nut finger tight, band on, tap around with rubber mallet as you tighten band. Tighten centre nut. Pray to the chaincase gods! :D
Dave.
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thornebt
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Re: Leaking primary cases!

Post by thornebt »

I've said this before on here but I found that getting a good fit between the case edges, fitting the Buckingham seal and then melting some tallow into the joint carefully with a heat gun managed to seal my chaincase perfectly. Never drips any oil and having achieved this I would be very reluctant to take it apart as I probably wouldn't be so fortunate next time. Cheers. Bruce.
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Taid
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Re: Leaking primary cases!

Post by Taid »

dave16mct wrote:Centre nut finger tight, band on, tap around with rubber mallet as you tighten band. Tighten centre nut. Pray to the chaincase gods! :D
Dave.

Nice to have my inclination confirmed .. already praying ..
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Now sold ... 1956 AJS 16MS Bitsa .. HSU 414 .. rebuilt/re-registered 1987
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ajscomboman
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Re: Leaking primary cases!

Post by ajscomboman »

thornebt wrote:I've said this before on here but I found that getting a good fit between the case edges, fitting the Buckingham seal and then melting some tallow into the joint carefully with a heat gun managed to seal my chaincase perfectly. Never drips any oil and having achieved this I would be very reluctant to take it apart as I probably wouldn't be so fortunate next time. Cheers. Bruce.
But that's the problem! It's a faff if you have too. The club one can be done and undone and remain oiltight without the faff. I've tried the Buckingham seal twice without using any sealant of any form and it failed everytime. I then used the club seal on the same cases without sealant as it was a tester when we first bought them and total success.
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