MOPED ARMY

Dont put salt in your tank you will ruin it. Straight vinegar to the brim and pour it out halfway and shake with small driveway stones inside to wipe the crud off as it eats away. Do that every other day until it's clean.

I used the pink rust remover and that got rid alot of the slimey stuff.

I agree with Nick. Evaporust or Metal Rescue.

Take a piece of bike chain about 8" long and put it in your tank and shake it up to remove all the loose chunks. (You can use rocks, or nuts and bolts, but a piece of chain is easy to get out)

Fill the tank with evaporust and let it sit for 24 hours (or more. It won't eat through metal.)

Pour the evaporust back into the jug and save it for later. It'll keep working until, well, until it doesn't anymore.

Then throw away the Por 15. Or return it. If you use it, you might as well throw away the tank. Same goes for Kreem. I've used them both. They absolutely suck and will cause nothing but problems. Google it and you'll see. I don't know how those companies stay in business.

Get Caswell. It's a clear epoxy sealant, it sticks to rust, covers holes and cracks, and NEVER comes off. It's beautiful. It's worth the money, and it just plain works.

I've done at least 20 tanks with it over ten + years and have never once had a tank leak or had the Caswell separate from the tank.

I've fought with the rusty fuel tank of my beloved 1964 Ford Econoline van since I bought it in 1981. Epoxy patches, more epoxy patches, soldering with a torch (not altogether recommended) and finally Kreem. It worked for about ten years and then began leaking. So, having read about motorboat fuel tanks, I layered the bottom with fiberglass, which held for another eight years or so. The latest and greatest--and quite successful--is Red Kote. Funny story: I used gallons of acetone to remove the Kreem and thought I was done. So I poured in the Red Kote, sloshed it around, and poured out the excess for re-use, as is recommended by the manufacturer. Surprise: huge clots of the Kreem coating came out with it. So I strained the stuff through cheesecloth in a funnel and kept it. The tank remains leak-free after maybe five years. I'd recommend Red Kote.

One hint: ask an auto radiator shop if they do anything with gas tanks. Some do, and the fellow I talked to here in Tinytown recommended RedKote over any of the others; it can be removed if necessary.

I like my POR15, I'm at 10 years on a Puch Maxi, 7 years on a Maxi, and 7 years on an MB5 tank all holding up great. I used the full kit and followed instructions to a T, was perfectly dry before I applied it.

My favorite method now is a quick rinse with somewhat diluted muriatic acid to get the heavy rust out. Rinse with water then an overnight soak with oxalic acid. It leaves what looks like a galvanized finish. No coating ever.

Oxalic acid does leave a coating after a water rinse . I've never treated the Simplex tank after the oxalic bath . Still seems fine . ;)

Nobody wants to do this

I just sealed my Campus 50 tank with Caswell, it was so easy. It set up in about an hour. I have it sitting on an oil filled space heater with a piece of flashing under it. Because its clear, it was a little deceiving whether or not it was completely coated as some rust flash will look coated and bare gray metal will look like the Caswell never got to it but I could see later it was.

Yeah, i can't believe people are still using nuts and bolts or rocks or whatever, then spending an hour getting them all out. Even if the chain gets stuck, you can grab it with a spoke or something and pull it out.

B ,I was guilty... Not anymore. 🙂

You can use salt and vinegar to make a slightly more acidic mix, it does not ruin your tank

Edit: Caswell is the only sealer I trust. (edited)

i've been using muriatic for years, any tanks that leak after a thorough soaking with muriatic, get the pinholes brazed.

i don't mess with any of that sealer stuff, i believe caswell and redkote are both pretty good products but after the kreem debacle i don't trust anything.