Rusty gas tank Farmall B.

My personal favorites (based on actual experience over the years):

POR-15 Fuel tank restoration kit. A bit pricy perhaps, but absolutely superb. You MUST follow the directions to the letter, but if done correctly, it's a great solution.

Electrolysis � essentially a mixture of soda (not baking soda) and water is placed in the tank, a battery charger is connected to a sacrificial anode and grounded to the tank, and the rust migrates to the anode. Can take up to a couple of days, depending on the level of the rust. This really does work and is actually my method of choice these days.

I�ve tied the mechanical processes, i.e., lots of small hardware such as nuts and bolts, and shake it around, sand blasting, and others, but I prefer the two methods I just identified. Especially if the intent is to preserve the exterior finish of the item.

Also, some radiator shops have a way of cleaning them out and they use something to line the inside. This helps plug up any pinholes you may have.