Repairing my gas tank

[979roadrunner]

I and others have used muriatic acid without issue in motorcycle fuel tanks, however I've since converted to using regular white vinegar (9%) it's not as fast as muriatic acid, but less hazardous to use (I never diluted my acid, BTW, just used it straight, then basted out the tanks with a pressure washer) and freindlier to the environment.
I like the chain idea, though I still prefer nuts as they have more 'edge' to them.
I extract them with a magnet.
Of course, the best way, if you have the wherewithal, is to open the tank, media blast it, weld up any holes, weld the tank back together, then epoxy it.
Next will be a ton of folks hollering how dangerous it is to weld on a gas tank, and it is, unless it's been blasted first, which removes the gas as well as the rust, leaving clean, bare metal.

[mike_of_bbg]

So I saw some of the pictures you all posted with rust in the tank and realized that the inside of my tank looks great! Except I have a very very slow leak near my back/bottom/right side of the tank. I already tried to use seal-all and that worked for a few months but I want to fix the problem. The paint in that area is already off so no harm there but I don't have access to a welder or anyone that does. I have the Caswell epoxy coming already so I think I will just use that inside, any thoughts?

Caswell is great stuff when you're already leaking. It's thick, bridges over holes nicely, and cures hard. I followed their instructions and all went well. Their kit does two tanks. You might be tempted to use it all on one tank, and if you want to that's fine. But still, do it in two parts. Once you mix the parts it's already starting to cure. It's thick stuff, too. Make sure you have some time to turn the tank.

Caswell doesn't necessarily recommend de-rusting the inside of the tank, as the rust (so long as it's surface rust - try to get large scales out) supposedly helps the epoxy stick. I didn't de-rust myself: I tried before I knew my tank was already leaking and $20 worth of Evapo-rust wound up on the floor. However, Caswell does cure clear. So if there's surface rust in there and you seal over it, you're going to see it as long as you have that tank.

Remember to go in while it's still soft (~40-60 mins after application) and clear the holes for the petcock and fuel gauge.

General recommendations for all tank sealing:

1. Make sure your tank is clean and BONE DRY before sealing (I let mine dry for 3 days after 2 acetone rinses, 2 water rinses, then 2 alcohol rinses)
2. Let your sealant cure for at least 3 days before putting fuel in the tank