Unbolt the gas tank from the rear of the vehicle using the 3/8-inch ratchet for the straps and a flat-head screwdriver for the hoses. If there is still fuel in the tank, pour it into a gas can or dispose of it properly.
Place the chain inside the gas tank, and pick it up to shake it. The chain bouncing around on the inside of the gas tank will loosen the flaky rust from the inside of the tank, which will get the loose stuff out of the way.
Pour out the flaky rust scale that the chain loosened from the tank and remove the chain.
Pour the metal wash product into the tank. This is going to clean up the surface of the tank and prepare it for etching. Twist the tank around so that the product can coat all of the surfaces. Pour out any excess metal wash.
Pour the etching product into the tank and allow it to work. You want to twist the tank around so that the product can coat all of the surfaces.
Pour the gas tank sealer into the tank, and roll the tank around so the sealer can contact all surfaces. This is going to coat the inside of the tank and allow it to stay rust-free for a long period of time.
Allow the gas tank sealer to dry according to the directions on the package. Then the tank is ready to be used again.Rust can affect every part of a vehicle, and when it hits the gas tank, you can have some big problems. If rusted metal goes into your fuel system, it can ruin fuel filters, pumps and even the motor itself. Removing rust scale from inside the tank takes some odd tactics, but you can do the work in an afternoon.