Awhile back, I purchased a 15 gal plastic gas tank for my 55 and it has a threaded vent on top. Since I have a vented gas cap should I plug this or will it be ok to leave as is with nothing connected to it? Thanks.
BJRs idea of the hose with the U is good. I might suggest a filter on the end of the hose to keep dirt out and more important, the addition of a roll over valve at the tank vent outlet with the hose hooked to that. If somehow the car gets upside down you won't have fuel pouring out of the vent.
Thanks for the feedback. I neglected to metion the 55 was a F-100 pick-up and the tank is below the running board. I think I will go ahead and plug it since my cap is vented.
No, if it is higher than the tank when the vehicle is on it's tires. When it's upside down,fuel will run out the vent. The vent hose would need to loop then run below the tank.
I unscrewed the “top” off the inexpensive remote rollover valve sold by Tanks Inc., added a hose barb, and put that assembly in-line in the vertical vent hose loop. The down leg drops out through the floor. Disclaimer: I haven’t tested it yet.
Gas will run out of the vented cap if you roll it anyhow unless it ends up laying with the gas tank filler higher than the tank. Main thing is that the tank is vented one way or the other or it becomes a vacuum container.
If you want a system that's leak-free even if it's upside down, route the vent line like the off-road guys do: http://www.pirate4x4.com/tech/billavista/Fuel_Cell/
I don't think you want the vent to go below the fuel level in the tank, or it may syphon the fuel from the tank.
Some vents have a rollover valve included in the design, like this one I installed in my RPU gas tank.
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