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

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

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.

push bike valve does the trick, if filling is a prob unscrew whilst your filling it, i don't have too......

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

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.