grafting section from one gas tank onto another... rust prevention?

[scouthead]

I am cutting the metal around a TBI fuel pump unit out of an old suburban gas tank, and grafting it into a project truck's tank. Both tanks have been bone dry for years, and I am not worried about the welding, just about corrosion afterwards.
I intend to use my mig...

Fuel pump welding will be done at the top of the tank, so at least it won't piss all over the ground if it sprung a leak, but what if i wanted to make/ add a sump to the bottom of the new tank? Anyway to corrosion proof?
Can I have it galvanized?
I have seen (and had two tanks sealed) with the red slime stuff, but neverthought it looked like it would last very long...

 

[BoondocK5]

Uhm, WOW!
Odds are that you won't have any problems, BUT, do you really want to test fate?
I use this stuff at work (building Aircraft structure)called B2 it's a gray sealant specifically made to seal surfaces that will be in constant contact with fuel. Just coat both surfaces with a liberal amount and press together then screw/rivet the two pieces together. allow to cure for approx 48 hours. Stuff works great, Never leaks when applied correctly. (proper prep work required, cleaning, sanding mostly)
I'm not sure if this stuff can be had commercially. I'll check and get back to you.

 

[scouthead]

swweeeet!

 

[4X4HIGH]

What tank are you wanting to graph the TBI stuff onto? It's not hard to put an electric pump into a tank that never had one before.

You need to be VERY careful if you cut/weld on a gas tank. I have a friend who needed to do some work on a gas tank that had been dry for 5 years but he still filled it with water first and after a couple minutes of welding he no longer had a tank to work on as it exploded and luckily didn't kill him.

 

[rdn2blazer]

NEVER NEVER NEVER weld on a gas tank or vessel unless you are trained and experienced with such a process. You can die very easily.

 

[rufusbooth]

Just say no to welding or cutting on a used tank.

Remember, you can get a new tank with the sump in it and the EFI sender has the same ring as the non efi tanks. They also just bolt in with no mods.

I personally am attached to my head and would be lost without it, thus you will never find me welding on a used tank.

Back to your original question. Because I will be welding on a NEW NEVER USED tank for one of my projects, the best way I have seen would be to do your mods to the tank and then have it hot dip galvanized. that coats the tank inside and out.


P.S, don't weld used tanks....did I say that before?

Cheers,
rufus

 

[Fordum]

I agree that cutting and/or welding to a used tank is best done carefully if at all. Not that I am worried, but I do wish you lived a little closer so I could come over with my camera........
Anyway, here is some information about aircraft B2 tank sealer.
http://www.vansairforce.net/articles/tank_sealant.pdf

And here is one place to get it.
http://www.aircraftspruce.com/menus/cs/fueltanksealants.html

J.

 

[owenst7]

You need to be VERY careful if you cut/weld on a gas tank. I have a friend who needed to do some work on a gas tank that had been dry for 5 years but he still filled it with water first and after a couple minutes of welding he no longer had a tank to work on as it exploded and luckily didn't kill him.

While I completely agree about the idea being extremely dangerous, I'd like to include that it sounds like your friend may have heated an incompressible fluid to cause the explosion.

Not saying that's why or that I've ever welded a tank, just saying it sounds like a dangerous idea to me. I wouldn't do it with water unless someone with that experience says to do so.