The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => Amal, Carburation, Fuel => Topic started by: ellis on 09.08. 2016 16:18

Title: A10 Gaskets and spacers
Post by: ellis on 09.08. 2016 16:18

Hi All,

Could someone tell me the correct order to put the gasket/s and spacer on. And do you need a gasket each side of the fiber spacer.


Cheers ELLIS

Title: Re: A10 Gaskets and spacers
Post by: morris on 09.08. 2016 21:05

Which type/thickness of spacer are you going to use? And are you using a drip shield?
The carb face should have an O-ring, so no gasket needed there if mating with a flat surface.

Title: Re: A10 Gaskets and spacers
Post by: bsa-bill on 09.08. 2016 21:57

I agree with Morris and any metal to metal should have a paper gasket in between. if the spacer is fibre , probably better to just give it a fine smear of joint compound.

Title: Re: A10 Gaskets and spacers
Post by: ellis on 09.08. 2016 22:28

Hi morris,

The spacer is a Phenolic 5mm thick  and am also using a drip shield. So would you put a gasket each side of the spacer and then let the carb O ring do the sealing against the drip shield.

Title: Re: A10 Gaskets and spacers
Post by: morris on 09.08. 2016 22:55

I am not really a firm believer in running long inlet trackts, so on mine I just have a thick (3mm) soft gasket between head and shield.
In your case I'd use a thin gasket, then the spacer, another thin gasket, drip shield, carb.
When tightening, I put .003 feeler strips between carb body and drip shield left and right, tighten the nuts until both strips can be pulled out with equal force, and then give both nuts an extra 1/4 turn.

Title: Re: A10 Gaskets and spacers
Post by: mikeb on 10.08. 2016 02:21

this is what a copied into my notes from some other part of this awesome forum:

Quote

Should be head , paper, drip tray, paper, tuffnol (phenolic) , o ring , carb
i.e, no gasket between tuffnol and the carb

some people dump the o-ring and fill with goo - some people make sure the o-ring is new/soft, else tightening onto a hard o-ring may bend the flange/carb body. don't overtighten bolt - i use blue thread-sealant, some use nyloks (i will next time i have some reduced hex ones)

Title: Re: A10 Gaskets and spacers
Post by: BSA_54A10 on 10.08. 2016 09:34

The purpose of a gasket is to allow movement of one part against the other and is required whenever two dissimilar items are bolted together or when ever you get a significant heat differential between parts of the same material.
An O ring is a type of gasket , as is silly-cone.
SO manifold-gasket-drip shield-gasket-heat shield-Oring- carb

Title: Re: A10 Gaskets and spacers
Post by: ellis on 10.08. 2016 18:39

Thanks for all your replies, I now know the sequence of gaskets and spacers.   *beer*

ELLIS