Gas Tank Swap

[jasonthomasfrance]

Howdy,

Well, my gas tank is leaking. It appears to be leaking from a section of the seam that holds the top to the bottom. I can get a plastic tank from an 80's something Grand Wagoneer. Will it swap into my 76? Or should I pull down the steel tank and just JB Weld it?

Other thoughts? I'm on a tight budget with a TX state inspection due by the 1st. And the plastic tank is free.

[Michael]

Dippy....I am assuming you are home??? If so welcome home... :D You probably could mod something for that tank. I would not think it would take much. But I am sure someone here would know. Just wanted to welcome you back.

[jasonthomasfrance]

Hey there! Thanks for the welcome! I made it back in December. And now I hear my wife may be going overseas for three months!

I was thinking the JB Weld would do it for the state inspection... But I'd still have to drop the tank to get at the seam. And if I'm dropping the tank, then I might as well swap in a new one.

Thanks for remembering me!

[Thomas DeBusk]

Hey, why not really weld it?

(Bet I'm going to get FLAMED for this one)

Seriously, I welded a hole in one of my gas tanks last summer. Safely.

The whole problem is getting rid of gas vapor, which is extremely dangerous. Many people don't realize that a partially full gas tank is much more dangerous than a full one. Liquid gas burns, but gas vapor explodes. And with even more energy when it's in a confined space.

Just washing out a gas tank usually isn't enough, either, because gasoline has a stubborn way of remaining in the seams and evaporating back into the tank, even after an aggressive soap bath.

So here's what I did:

I washed it out a lot with soapy water. Several rinsings. Then I left it out in the sun for several days. I think a couple of weeks. Then I hooked up my air compressor and ran air through it a few hours. Then I left it sitting and smelled to see if there was still an odor. There wasn't any.

But even so, when I finally got to doing the welding, I hooked up my shop vac to run air through the tank. Believe me, there were no fumes to ignite. I've heard of filling the tank with water while you actually do the welding. That seems like an even better idea to me than what I did.

Flame on!

[andy d]

i've seen punctured gastanks soldered. the area is cleaned. to bright steel. a big ol' iron was heated witha torch. the iron was then held 12" above the hole and solder was touched to iron.molten solder sealed the hole. filling a gas tank with water doesnt work well, the water doesnt allow the metal to heat enough to melt the solder. jb weld would work, the steel has to be bright,and the stuff needs to set up overnight.i also final clean with carb cleaner or brake clean.

[ January 29, 2002: Message edited by: andy d ]</p>

[Lindel]

You can weld, with the tank full of water, because the metal heats so quickly from the arc, that the water can't absorb the heat, as opposed to soldering the tank. Soldering would be a lot safer, with the possibility of gas fumes, since a hot soldering iron wouldn't be as likely to ignite the fumes.

Both are good options, but a new tank would be quicker.

Jason, if you do go with another tank (the poly one you told me about), be sure that you get the coffin to go with it. Mainly because with a poly tank, you won't be able to use straps to hold it up.

[jasonthomasfrance]

Oh man... The coffin. I didn't even think about that. I'll have to call the guy to see if he still has it. Or if it's still under the jeep.

If I can get a rental car for the wife and I, I think I'll try the welding with it filled with water. I'd have the time then for dropping and welding.

[jasonthomasfrance]

Could pressure buildup be causing the leakage? This now kind of ties into the "Different Symptons" thread.

I talked to the PO tonight. Went over to his house and picked up the coffin and plastic tank.

He thought it wasn't really a seam split as it was the return line clogged or disconnected.

He said he had pressure build up and leakage too. He said it was leaking from the top of the tank near the lines. Which coincides with where I'm leaking.

And there is A LOT of pressure build up. Do I need a vented gas cap on my 76? Maybe the return line or vapor line whatever is plugged or something. I'll take a look when I drop the tank.

[Lugnut]

Check out CaswellPlating.com. They have a 2-part epoxy made for sealing gas tanks. I have not used it but did see it in a mag. article in the past and the writer was impressed.

[jasonthomasfrance]

Help needed! In the next couple of days I'm going to drop the tank! What should I have on hand to replace. I 'm pretty sure the tank does not have a charcoal canister. I'm going to get some rubber tubing, about how long should I get it?

Any other things I should?

[Lindel]

Yes, you do need a vented cap. The wife's will leak horribly with an unvented one, and her's is a 78.

[jasonthomasfrance]

Hmmm... *wink wink* how do I make a vented gas cap?

I just the article on a gas tank swap in the Tech Library. Good read!

[ January 30, 2002: Message edited by: dippythelovebug ]</p>

[Sgt. Dave]

Don't need to make one, just get the proper year cap at any parts store. They look the same,more or less. If they have a real, honest to goodness actual book to look the cap up in, there will be a footnote "vented".
I hate computer terminal parts screens.

[jasonthomasfrance]

I've been to the two part stores around here: OReilly's and Autozone. And they say they don't have vented caps for my jeep...

[Lindel]

Easiest way is to "nip" a small slice out of the rubber gasket, on the non-vented kind.

But wait until after the inspection to do it, just incase they pressure test the cap. Or, get two caps, just for that occasion.

[jasonthomasfrance]

Oh yeah! I passed state inspection. Turns out I went to the guy that did it last year for PO. Didn't even know. BSd with him for about 30 minutes. Passed the beast! Hoohoo!