mystery fuel hose...

[KFunk]

so today I was workin on my alternator.. and I noticed a mysterious plugged hose down below my battery. I pulled on it slightly, and it broke off. Nothing came pouring out, seemed dry inside. It was a metal line coming along the underneath the frame rail, with this brittle cloth covered fuel line hose clamped onto it, and a screw plugging it. I had no way of plugging it right then. I let the car idle a little, and didn't see anything pour out. I assumed it musta been some relic of the long-gone emissions system.

So.... I go for a drive, and stop at a store, hear some dripping... get out, and there's a big puddle underneath the car. I smell it, and yep, its gasoline! uh oh. It wouldn't stop trickling out. I ran into the store and got a cork real quick and jammed it in there.

Now why in the world would I have an extra fuel line there?

[cj]

It's part of the fuel evaporative system.

Cris

[KFunk]

ok... so where does it come from, and what does it do?

[cj]

What year is your car?

Cris

[KFunk]

74

[Zenon]

That metal line on the driver's side is actually the fuel return line*, not the evap line. The factory low-pressure carb fuel supply setup from '73-on had a regulator valve that would return excess liquid fuel to the tank, thus keeping it continuously flowing and cool so avoiding vapour lock on hot days in heavy slow traffic. The evap line is a smaller rigid blue plastic and runs alongside the main clear plastic fuel supply line through the cabin - it connects the filler neck and charcoal cannister and only has fumes in it.

That return line is usually abandoned when people install webers, though I have seen many cases where it wasn't plugged off at the tank and then started leaking many years later. If you are not using it, disconnect it and plug the fitting at the tank! You can then plug the end of the line to keep dirt out in case you ever want to use it later, say, if you go EFI.

*On tiis, the steel line is the high-pressure supply and the plastic line is the return.

regards,

Zenon

[cj]

I stand corrected. Thanks you for clearing it up.

Cris

[KFunk]

ahh ok, yeah it'll be easier to close it off at the tank. I think I know which one it is there, and always wondered where it went. Well now I know, heh.

[Mike Self]

the firswt time you fill the tank (presuming it's still connected at the tank end) you'll start siphoning gas out of the tank. I learned this the hard way--but at least nothing caught on fire!.

Some folks do a little re-plumbing and use this line for the fuel feed line, bypassing the plastic line that runs thru the car 9Not really necessary, the plastic line is self-sealing if there's an interior fire). If you're gonna do this make sure the metal line isn't rusted someplace under the car.

cheers

mike