What have F.I. guys done for a fuel tank breather?

I'm ordering some bits from think tomorrow and was going to add one of their tank breathers to the list. Just wanted to get an idea of what others have done.

After 3 track days - and 2 black flags for fuel spilling out of the back of the back of my car!, - the best tried and tested method I have found is - a piece of fuel pipe off the breather on the fuel tank, - looped 360 degrees then with a normal fuel filter on the end.

Never had a problem since. Plenty of air to breath and no problems now on trackdays...

Hope this helps,

Regards,

Mark.

think do a nice red anodised one way valve but its £20 ish i think

I've p[osted this a few times, but............

If you are after a non-return, or check, valve for the breather, find a Metro. There is a nice little valve in the breather tube. You'll find it up the B pillar on the driver's side.

Cheers,
Syd.

quote:

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Originally posted by marc n
think do a nice red anodised one way valve but its £20 ish i think

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They supply both in tank and in hose ones. I have yet to make my mind up but Im going towards a tube with valve in the end.

Theres a thread running at the moment about a Think one which is causing problems. Ive heard some good results with fish tank type one way valves but Ive also heard people say you need a "2" way valve in that it is an NRV in one direction to prevent fuel leaking but allows air in and out.

Rgds - hope the builds going well
Rich

Check out this on Ebay. I've just fitted one on my tank, seem like it does the job, and it's cheap £6.45

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=8068077217&ssPageName=MERC_VIC_ReBay_Pr4_PcY_BIN_Stores_IT

Sorry, don't know how to do the link thingy

Steve

Where do they fit Steve?

Rgds

Rich

Whoooo the link thingy works

So that's how you do it

You just fit it with a petrol pipe onto the tank vent. The valve has a ball bearing affair that lets the tank breath, but when tipped upside down and has a large pressure behind it, it closes.

seems to work, when you blow through it.

Which hose do the in-hose version fit into?

Just wondering as I have no spare connectors on the tank

I've got one of these fitted and they "sort of" work ok ish....
The principal of opperation is as stated. There is a small steel ball inside the valve that sits on a seat with 3 radial grooves so that air can both enter and escape.
There is also a seat at the top of the valve that does not have the radial grooves. If the valve is turned upside down or fuel surges upwards, the ball seals on this seat stopping the flow of petrol.
In principal this is fine....
However in practice problems can occur.
On very hot days the rate of expansion of the fuel can be high enough to lift the ball and seal the vent. Thus building up pressure in the tank.
This has only happened on one occasion and the circumstances were as follows.
The car was pushed out of a cool garage backwards and left in the direct sun onto the rear of the car for about 1 hour. The tank was about 1/4 full.
I then drove the car for about 10 miles and pulled into a filling station.
On removing the cap the tank was under considerable pressure.
As I am running FI with fuel return this did not cause me a problem but had I been running carbs I'm sure it would have.
This is the only occasion that this has happened (I have checked on many occasions) I think the more expensive valves from Think would probably be more reliable but I guess you pays your money and takes your choice