BSA Owners' Club Workshop Discussions

The BSA Workshop => Twins => Topic started by: malc rhodes on 27 Jul, 2022, 10:38

Title: Anti flowback grub screw
Post by: malc rhodes on 27 Jul, 2022, 10:38
I'm having trouble finding the anti flow back grub screw for a A10 76-1401 does anyone know where I can get one , I had to drill the old one out so I'm a bit stuck
Title: Re: Anti flowback grub screw
Post by: idie on 27 Jul, 2022, 11:03
I made mine a few years back. Unfortunately I can't remember if it were a 5/16 or a 3/8 whit size, just try a bolt in the threads. Cut the end off and slot it, it is very short only about 4 threads long.
Title: Re: Anti flowback grub screw
Post by: malc rhodes on 27 Jul, 2022, 11:12
Thanks I'll just see if I can get the real thing first
Title: Re: Anti flowback grub screw
Post by: Spaceman on 27 Jul, 2022, 13:44
It's 3/8 BSW but doesn't look like it is readily available unless you want to buy one from the USA!
Title: Re: Anti flowback grub screw
Post by: DAVE BRADY on 27 Jul, 2022, 14:32
Hi,

Try C and D Autos.  They do not have a web shop so best to ring them up.  01564 795000.

A modification to this non-return valve is to drill the case out so that the ball and spring can accessed from behind the pump.  So once the blanking screw is securely fitted the ball and spring can be checked/replaced with out splitting the cases.  The A65 ball and spring is used instead of the A10 and the ball sits on the back of the pump ala A65.

Dave.
Title: Re: Anti flowback grub screw
Post by: malc rhodes on 27 Jul, 2022, 21:15
Thanks looks like I'll be getting some 3/8  off e bay , I'm aware of the a65 conversion but I'll stick with the original set up it's lasted this long thanks again for your help
Title: Re: Anti flowback grub screw
Post by: malc rhodes on 29 Jul, 2022, 19:00
If anyone else has the same problem I got some 3/8 bsw grub screws from Spalding fasteners who are on e bay they'll need grinding down a bit though