Compiled by Mike Simmons, contributors listed below
Q: How do you restore an old gas tank? The gas has been sitting for 10 years....
I cleaned mine out by flushing it with water. You might try breaking up the varnish with gasoline first. I then used a coating for the tank, Stoddard has it, or check Hirsh in New Jersey, make sure the over flo tubes are clear, use a wire as these releave pressure from the tank. If you wish you can wire brush off the rust and paint the area with a decent protective paint. If there are holes, you can solder them, or tin the area. Make sure all the fumes are out before you apply any heat. Washing with a garden hose for an hour, and then using a shop vac in the blower position for another hour will dry it.
Chris Lonie wrote,
I cleaned mine with b-12 and then took it to a radiator shop for an acid
flush. They wanted to puncture it to drain it and then reweld it. I said no way and just had them flush it. Then I used the POR-15 prep and sealer. Next time I would use a quart of sealer rather than the pint they recommend to be certain you got the whole interior. I haven't had any problems in 500 miles or so.
Robert Harrington wrote,
I have taken several tanks to the radiator shop for acid clean-out. It
works fine. You might want to rinse it before installing it however and
don't let it lay around for long between getting it back from the radiator
shop and re-installing it as it will quickly develop a light rust over the
freshly etched surface. Some have used a tank sealer cleaning, and you may want to (Stoddard, Eastwood and others make a good one) but if your tank is in good shape, there's no need to bother in my opinion.
Steve Bareis wrote to remind us about a story The Maestro wrote recently in The Registry Magazine about a car that was brought in with a problem. It turned out to be gas tank sealer in the carb and fuel line system. Steve's suggestion is to not take any chances and buy an NOS tank.