I was wondering if anyone has had experience in sealing a gas tank? I think mine is rusty inside and putting lots of junk in the filter. I've been on line reading about various sealers. Some claim they are bad news and will eventually fail. I've seen two types--Urethane, moisture activated paints(KBS, POR15) and another non-moisture activated(Bill Hirsch, for one). Someone said the urethane style can break away forming a "floating plastic bag" in the tank. But then another person said the other style can wind up as a gummy mess in your fuel.
Has anyone used these and were you pleased with the results?

I cut out two roughly square holes in the bottom of the tank where the pinholes were, sandblasted the inside (the holes were about 4"X4" so allowed access with a sandblasting gun). I butt welded patches back in, treated with metal-ready and coated with POR gas tank sealer....painted the outside and it looks like new. Like Chris said, I think the por-15 works well but the surface has to be dry and hydrocarbon free.

Dean

Thanks to all for your advice. I guess having a perfect surface to start on is the key to avoiding the paint peeling.

I am a HUGE fan of the POR15 kits. I have used them a number of times. Several of my cars have treated tanks as well as my tractor. You just have to follow the directions exactly and take your time to make sure it's dry between each step. I normally figure it's about a ten day process to make sure I am not rushing things.

I did my tractor's tank about ten years ago and it's still good as new. We even get ethanol in our gas and the lining is not effected.

The lining projects I have seen failed have been due to the person trying to take short cuts or in a hurry.

There is an old time radiator shop that gets my tanks that have big holes in them but if it's still sound, pour in some nails, shake the tank to break everything loose. Pour out the nails and loose rust (yes it will take some shaking to get all the nails out from behind the baffles). Then use the POR15 kit.

Chris

If you can find an old time radiator shop that will clean your tank that may be what you need.
Sometimes they will offer to coat the tank for you. If they do, ask for names of people
for whom they did that in the past and check out their references.
Unless you can get the tank really clean first, I would not consider coating it.
--
George Downs Bartlesville, Oklahoma

I had a gas tank rust problem in the one I am presently working on. I cut 3 sides of a square (about 12")in size on the top of the tank and just folded it back to about 90 degrees. This gave good access to the inside of the tank which I wire brushed using a small electric drill. After thorough cleaning, I poured sealer in, sloshed and brushed it around so it covered everything except the inside of the top. I bent the cut portion back in place, made several short welds around the cuts, then ran a bead all the way around to seal the cut. I then poured in about another pint of sealer, held the tank upside down and moved it around to coat the area. No way to be SURE that part was coated completely, but I am sure the bottom and sides were coated. You will get some of the sealer in some of the threaded connections, but it is easily cleaned out.
It has had gas in it for over a year and no leaks. Hope this information is helpful