- 1). Begin by removing the gas tank and draining all of the gas from the tank. Presumably the tank has been sitting idle for less than 10 years and there are no rust holes. If there are rust holes present in the tank, either replace it with an after market tank or take it to a professional restorer.
- 2). Partly fill the tank with acetone or paint thinner and then dump in several handfuls of lug nuts. Cap the tank and have a partner help you shake the mixture around for 30 seconds to 1 minute at a time. Dump out the old acetone and replace with new. Perform this process until the acetone coming out is clear and not tinged from dissolving varnish.
- 3). Drain all chemicals from the tank and remove the lug nuts. Let the tank dry overnight.
- 4). Following the instructions that came with the gas tank liner kit, prep the tank for lining and then line the tank with the anti-varnish chemicals. Let the liner dry and then make sure none of your petcock valves are clogged.
- 5). Reinstall the tank, hook up your gas lines and move on to the next restoration step.
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