BSA Owners' Club Workshop Discussions

The BSA Workshop => Twins => Topic started by: chrisx1 on 10 Aug, 2024, 17:10

Title: Oil leaks
Post by: chrisx1 on 10 Aug, 2024, 17:10
I have an oil leak from behind the kickstart shaft and one from behind the gear lever. Are these preventable?
Title: Re: Oil leaks
Post by: Alan wray on 10 Aug, 2024, 17:47
Is it a big leak. I get a mist leak out of them and i dont think there is much you can do.
Title: Re: Oil leaks
Post by: cornishbob on 11 Aug, 2024, 09:25
smile and say you have a custoimized lurication system
Title: Re: Oil leaks
Post by: chrisx1 on 12 Aug, 2024, 07:48
Yes big leak. Losing all my gearbox oil. Possibly another leak elsewhere. I have a uv light which shows up oil as a milky substance. They are the only two places that I can see.
Title: Re: Oil leaks
Post by: Alan wray on 12 Aug, 2024, 08:05
Are you running a ROYAL STAR. If so, Has the inner timing cover got the little drain hole at the bottom like a C15/B40. It could be blocked. Im not that up on twins.
Title: Re: Oil leaks
Post by: chrisx1 on 12 Aug, 2024, 15:14
It's a 1968 Lightning. Well the bottom end is barrels down.
Should there be a seal behind the kickstart shaft and gear lever shaft. I can't really see on the diagram in the manual.
Title: Re: Oil leaks
Post by: ChrisG on 12 Aug, 2024, 15:49
There are no seals behind both shafts as theoretically there is no need. The gearbox is sealed off from the outer case by the 'Bearing Cover' (round plate). Clearly something is amiss.

Sorry for stating the 'blee**** obvious but, is the gearbox oil level too high? The dipstick should be 6.1/2" long from under the thread to the tip and 5.5/8" to the top level marker. Both are below the Kickstart shaft and Gearchange shaft.

If that's not the problem, maybe the round bearing carrier plate joint may be damaged.

Hope this may help.
Title: Re: Oil leaks
Post by: chrisx1 on 12 Aug, 2024, 17:00
I suppose it could be overfilled. I don't have the dipstick plug just an alloy one like the primary inspection covers.
Title: Re: Oil leaks
Post by: chrisx1 on 12 Aug, 2024, 17:32
Thanks for stating the obvious. Sometimes I miss what's right under my nose. I had overfilled it grossly. I must get a proper cap with the dipstick attached.