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fuel tank breather
scoop - 5/9/07 at 09:00 PM

Would someone please confirm i need one?
And if so can i use the pitbike ones for £2 on ebay?

RazMan - 5/9/07 at 09:06 PM

You definitely need one unless your filler cap is vented. In theory the cheapy eBay ones should work.

scoop - 5/9/07 at 09:27 PM

Lovely ta
ill order one now then

[Edited on 5/9/07 by scoop]

matt.c - 5/9/07 at 09:57 PM

I have heard that this needs to be a one way valve not just a breather for the SVA?

nitram38 - 6/9/07 at 03:07 AM

quote:
Originally posted by matt.c
I have heard that this needs to be a one way valve not just a breather for the SVA?


If you have an injection with a fuel return, then you will need a two way valve, otherwise your tank will pressurise.
No requirement for sva for a valve, but you can buy two way valves that will close if inverted from think automotive in twickenham.

twybrow - 6/9/07 at 06:57 AM

I have an injection engine and two ports in my tank i need to block up. I was planning on just using two valves, but I guess at least one of them would need to be two way then....?

scoop - 6/9/07 at 08:31 AM

Its a bike carb'd pinto so no fuel return.
How sure are you Nitram?

RazMan - 6/9/07 at 08:50 AM

Even a carbed system needs a two way breather imo. Have you noticed how much pressure can build up in a tintop fuel tank when it's left in the sun?

DarrenW - 6/9/07 at 10:06 AM

On my pinto set up ive used a fish tank one way valve (plastic bodied valve used in aerators to stop water siphoning out of fish tank) and also a breather filler cap. No problems with this set up and cost pennies. I just mounted the breather high up in case i fill the tank too much up the filler tube.

twybrow - 6/9/07 at 11:21 AM

So if I had a one way valve and a breather would that suffice? I cant see the point of a one way valve, if you then have a breather anyway?

Bob C - 6/9/07 at 11:25 AM

I was looking at kieth tanner's build diary the other night - he had a 2 part solution, a breather valve and a "roll over" shut-off. That's the only solution I've seen that makes complete sense.
Mine 'breathes' via poor sealing at the filler. No problem at SVA but should be sorted properly......
Bob

nitram38 - 6/9/07 at 05:32 PM

quote:
Originally posted by scoop
Its a bike carb'd pinto so no fuel return.
How sure are you Nitram?


Check the manual as there are no sections on fuel tank requirements.
As long as your tank does not leak, it will pass.
The valve is for your protection.
Another alternative is a long piece of fuel hose that bends down just past the bottom of the tank and then back up to your highest fuel filling point.

scoop - 6/9/07 at 08:28 PM

Thanks all.
Ordered one of the pitbike ones off of ebay. Delivered for £3. I'll give it a go for that price