Talk:Removing rust from a gas tank
I'm no chemist and any chemistry in the vinegar section was found on webpages with no references, so feel free to correct it.
JB weld does not work in any application where it is exposed to gasoline. I tell you this from experience. gasoline dissolves it no matter what the manufacturer claims. the only successful patch to a gas tank using an epoxy resin was where I plugged the hole with wax and then used JB weld over it. it lasted a couple of weeks. best advise is to weld it. and don't be afraid of it blowing up. let it dry out overnight or blow some air through it to get the vapors out and it will be fine. test it with a match or a torch first if you want to, and keep the gas cap off.
For plastic gas tanks with a leak I have used a soldering iron or a hot flathead screwdriver to melt a hole shut. I also used the technique on a leaky plastic canoe once. another useful technique is to use a filler plastic. I have used ice ream pail lids cut into strips to patch gas tanks. I lit one end of the strip on fire and let it drip over the crack. It worked great on more than one leaky tank. But one time it didn't. I think there was some kind of incompatibility in the two kinds of plastics. it's worth a try.