David Jenkins
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posted on 20/1/03 at 09:10 AM |
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Fuel tank vent
I am the proud owner of one of Mr PTM's finest fuel tanks, which I'm currently plumbing in.
My question is about the vent pipe... obviously necessary to prevent the tank collapsing when fuel is taken out, but I don't know what to do with it!
(no rude responses please!)
I was thinking of making a one-way valve to fit on the inch-long tube - easy enough to make on the lathe.
My main concern is whether I can mount the valve just above the level of the top of the tank (where it is now) or whether I need to extend the tube to
a higher point (which would be a pain).
What have other people done?
David
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kingr
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posted on 20/1/03 at 12:20 PM |
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I believe a one way valve will not be what you want, since the air vent is also used when filling the tank to stop the air being displaced having to
come back up the filler tube.
Kingr
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scutter
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posted on 20/1/03 at 12:55 PM |
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Rally designs do a tip over valve that goes instead of a vent valve, this only closes when inverted. The down side of this is it's £14.80+vat.
Perhaps you could make somethying similar.
Take care Dan.
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Jon Ison
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posted on 20/1/03 at 02:12 PM |
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push bike valve does the trick, if filling is a prob unscrew whilst your filling it, i don't have too......
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David Jenkins
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posted on 20/1/03 at 03:25 PM |
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Jon,
Pretty much what I was thinking - I'm going to make the valve using a spring-loaded ball bearing (closed on 'blow', opening on 'suck'). The input
pipe is a decent diameter so I shouldn't get much blow-back with a skinny 'unleaded' nozzle.
My concern was whether to put this valve just above the tank - but it should be OK as it will be closed near-enough all of the time, and only open a
fraction during 'air-in' periods.
cheers,
David
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CairB
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posted on 20/1/03 at 07:55 PM |
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I've got a PTM tank. I fitted a vent pipe to the sender unit flange, looped a piece of tubing up and over under the rear panel down to a valve from
the Sierra fuel pipe assembly, mounted on the tank strap, then a drain pipe down to the bottom level of the tank. The valve only blocks when upside
down which I hope I never experience. The tanks been emptied a few times in 1.3K so far with no ill effects.
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