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Fuel Tank

Spring 2003

Note When this page was initially posted there was concern among some readers that the tank had somehow been glued back together with JB Weld. While JB Weld was used to fill a few pin-holes, it is not being used to hold the tank together. It has only been used to rebuild the upper support flange—the factory seam-weld that holds the tank together is completely intact. The goals of this repair were to: stop the rust from progressing, keep the tank from falling out of the car, and improve the tank's general appearance. I believe that the repairs discussed here do not make the tank any less safe than any other 30-year old gas tank would be.

When the fuel tank was removed during the disassembly phase of project I realized that the tank had some serious rust problems. I had to figure out how to restore the tank, or make plans to find another one.

There was evidence that significant amounts of rust had formed between the top and bottom halves of the tank where they were seam welded together at the factory. If you asked me, this is a pretty poor design. But what the heck, most of a 2002 was designed to rust.

To remove the rust and save the tank, I decided that the top half of the flange would to be removed. I would then make replacement patches and glue them in with JB Weld—a metal epoxy popular with shade-tree mechanics and pluggers everywhere.

gas tank 01

Rust can be seen between the layers of sheet metal that form the support flange.

gas tank 02

The top half of the flange was cut with a Dremel tool just on the outside of the seam. The process was slow, but patience is a virtue.

gas tank 03

The flange was peeled back as the cut progressed. I was careful to make sure that I did not cut through the bottom half. There were a few spot welds to split in the corners.

gas tank 04

With the top half of the flange removed, the extent of the rust was now visible.

gas tank 05

Oh, what a surprise, even more rust.

gas tank 06

The rust was removed with 80-grit discs and a wire brush. I tried to make it look as good as I could.

gas tank 07

With the rust removed, the remaining tank flange was painted with POR-15.

gas tank 08

The pieces of flange were removed in convenient sections. The outlines of each section were transferred to some cardboard.

gas tank 09

The cardboard patterns were used to cut new flange sections out of 20 gauge sheet metal.

gas tank 10

The sections were glued on to the tank with JB Weld and clamped overnight. When dry, the excess metal was trimmed off and holes were drilled for the mounting flanges.

gas tank 11

The finished product.

Fast-forward to the end. I knocked some of the dents out by reaching into the tank with a body hammer. Then the inside of the tank was treated with a POR-15 fuel tank kit. A few remaining pin holes were patched with JB Weld, and then the tank was painted with POR-15 and POR-15 Chassis Coat Black. It turned out looking pretty respectable. While it's definately not concours quality, it certainly looks 100 times better than it did - and for very little money.

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