The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => A7 & A10 Engine => Topic started by: Angus on 04.08. 2017 11:41

Title: Gasket sizes
Post by: Angus on 04.08. 2017 11:41
1960 A10 and 1961 A7. Just bought new timing cover and primary gaskets., from a supplier some love and some hate but local to me and so when they did not arrive promptly, I want a collected them. Anyway they seam too large/wide lots of over lap on the outside. I have read welsher that the mating surfaces can be irregular, so is this what suppliers are now doing to get around it. Do I just go around with a Stanley blade after its all done up and proved oil tight to clean up the excess (note it is already done up on the A7 and oil tight after a short ride).
 
Title: Re: Gasket sizes
Post by: JulianS on 04.08. 2017 13:13
The new gaskets do seem to be overwide and I think it may just be for manufacturing convenience.

Photos shows a NOS timing cover gasket (wafer thin) laid over an inner cover, it is not as wide as a new one but still does not fit perfectly.

Edge trimming is the only way with new, or make your own with a suitable material.
Title: Re: Gasket sizes
Post by: Angus on 04.08. 2017 13:42
Thanks Julian

I will get the Stanley Blade out.

These have about 1mm sticking out almost all around. Appeared to fit wel on offer up and ok with some screws in to hold in place as I was not sure.
Title: Re: Gasket sizes
Post by: BSA_54A10 on 05.08. 2017 10:15
Get a scapel from a hobby store and use that or a linoleum blade is Stanley still make them or you will not be able to follow the internal curves.
Title: Re: Gasket sizes
Post by: bikerboy on 15.08. 2017 00:18
Even more worrying are the latest sets of rocker box gaskets we seem to be getting

A friend of mine done a top end overhall and within 15 miles oil was pouring out. As a favour I took the rocker box off at the weekend new gaskets etc and within a mile it had blown in exactly the same place.

Both head and rocker box have been faced up but the gasket is only catching my about 2 mm at the front of the rear compartment if you know where I mean about 10 mm from the bolt.

I am ordering a set of copper ones now taking your rocker box off 3 times in 15 miles is not how I like to spend my time  *smile*