Best way to vent a single nippled tank
^^Or modify your neck^^ Otherwise, you need to get that "nipple" up as high as you can, and not sure where you would end it at the rear. Otherwise, run it clear up front, high in the engine bay. You could plumb it into the non pressure side of the PCV system (air filter bonnet) to contain fumes
You cannot just run it, say, up high in the trunk, then down again, because it will make a siphon. The way that the 69/ earlier stuff was done forms a "vacuum break"
The 60/ earlier system tapped into the filler up high, went up against the top of the rear quarter, then down along the filler tube, through the floor gasket, and ended (open) in the inside of the rear frame rail. This WILL siphon in extreme cases.......such as filled clear to the top, and parked on a severe sidehill with the filler neck on the lower side. But it will only siphon until the vent tube opening into the filler tube is "above water" and then it will "break."
^^Or modify your neck^^ Otherwise, you need to get that "nipple" up as high as you can, and not sure where you would end it at the rear. Otherwise, run it clear up front, high in the engine bay. You could plumb it into the non pressure side of the PCV system (air filter bonnet) to contain fumes
You cannot just run it, say, up high in the trunk, then down again, because it will make a siphon. The way that the 69/ earlier stuff was done forms a "vacuum break"
The 60/ earlier system tapped into the filler up high, went up against the top of the rear quarter, then down along the filler tube, through the floor gasket, and ended (open) in the inside of the rear frame rail. This WILL siphon in extreme cases.......such as filled clear to the top, and parked on a severe sidehill with the filler neck on the lower side. But it will only siphon until the vent tube opening into the filler tube is "above water" and then it will "break."
