The Stovebolt Site Forums The Shop Area General Truck Talk Leaking gas tank shut-off valve

I have a leaking gas tank shut-off valve on the bottom of the gas tank. It's a small drip, however, it's leaking and should not be. What would be the safest way to replace it? I'm very concerned working around the gas tank. There is approximately a half a tank of gas in there right now. I need a good safe procedure. All suggestions are greatly appreciated.

Most likely you will have to empty the tank, and remove the valve, and clean and inspect it.

Siphon the gas out of the tank (half a tank might be 7-10 gallons).

Many valves are all metal. If the metal is scored/pitted/etc, you might have to replace it. You might get away with simply cleaning and reassembly of the valve (if it only has removable dirt/deposits on the metal)

If the valve has a rubber/etc seal, that part might need replacing.

I've had to do this several times for various reasons

I use one of these transfer ...pumps...

My tank is behind the seat, I removed the sender and pumped from there.
I did have to attach a rod to the pump hose to keep it straight.

It worked surprisingly well

Replica fuel valves are now available for the AD years, not sure if yours is the same

...example...

Have you tried tightening the packing nut?

Leaking gas tank shut-off valve

Pre '68 Dave,

Good tip! I just went out and tightened the packing nut. It seams like the drip stopped, however, I'll keep my eye on it today just to see if any gas dripped into the plastic bucket I put below it. LEAK is a four letter word!

What is the reason to continue to use a shut off valve?

Bartamos,

Good question! This shut-off valve is only there because its original to the truck. It had not been leaking until I shut it off to install my new fuel pump with filter and carburetor. I may have loosened the packing nut slightly and therefore that's when the small drip leak started occurring. I'm trying to keep the truck as original as possible.

Anyway, I'll keep my eye on it today to see if it's still leaking. I prefer not to mess around with it too much since monkeying around with gas tanks and gasoline makes me a bit nervous. If I have to replace the valve I'll deal with it in hopefully a very safe manner. There are replacements available for this shut-off.

Consider eliminating a leak source by plumbing direct to tank while you are at it. Unless someone here has a good reason to have it. There are none on later eras. If you need to stop fuel from leaving tank, squeeze the rubber hose.

To prevent cletis from moving this topic to the HiPo Shop Forum.
Carl

Another good reason to get rid of the shut off is because that is where the trash out of the tank settles. An even better idea is to use the top draw like was used from 1954 and later.

Good Idea Crenwelge. I have modified the 54-59 sender/pickup to fit suburban's, so if the mounting flange fits, the tube and float arm can be modified. (somewhat). Carl is wrestling with an imbibement problem and is posting willy-nilly in a tutti-frutti hokey-pokey fashion. In other words, nurse Ratched is looking for him. (insert emoticon)

Well,
I just brought a truck home with a new tank in it and no shutoff valve, I'll put one back in as soon as I run it out of gas.

The shutoff valve is real handy if you need to:
-Replace the fuel pump
-Fix any lines or leaks between tank and fuel pump
-If you have a glass bowl fuel filter on the pump and want to remove it to clean the screen.
-to service any other fuel filter you may have installed lower than the gas tank (fuel level).

Grigg

Yes.
If you don't carry some of those in your pocket or truck you could carry the original or a replacement shutoff valve already installed in the bottom of the gas tank.

I'm just advising if there is a way to eliminate a leak source, a malfunction-able item, then it's a good idea. Lot's of ways to pinch off a hose on the hiway, if you really needed to, but that would require you to have whatever part you are replacing with you also. If it's a necessary part on a gravity feed system, OK.

I value a fuel shutoff valve more for what it does and how easy and safe it makes common task and I don't worry a bit about it leaking.
If it leaks fix it, same as any other leak.

I thought you were asking for a good reason(s) to have one... When you asked did you already know there wouldn't/couldn't be any reason good enough for you?

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Bart -- Ya know, it ain't the end of the world if someone disagrees with you.