Cleaning rusted gas tank with Citric Acid

I used Muratic acid. Works very well. After a shot time of soak neutralized with healthy rinse and baking soda.

If you put some easy to fish items like large bolts and nuts in the tank and tumble it. This will help break off the flakes of rust.

I use a length of chain in the tank to knock the crud loose. Works great and MUCH easier to remove than nut's & bolts. Just hook the chain with a piece of wire and pull it all out at once.

The gas tanks I get all go to my local radiator shop and get acid cleaned (don't know what acid they use) and put in a hot tank. Then after that they get sealer put in them and they are all ready to go. Just had a tank off a john deere 620 done for about 100 bucks. It seals all the pinholes. They said it will even seal up to a 1/4" hole if they tape the outside, I wouldn't recomend that though.

A great tank cleaner is some small chain welded onto about 2 feet of 3/8 rod and chucked to an electric drill. Just hang on tight!! 😊

As far as repair/coating the best (IMHO) is POR-15 (google it) because it comes with a gunk and rust dissolver as well as a thick coating that will fix even severe rusted out sections. Just put duct tape on the outside to support the sealer til in hardens.

I'll second that! POR-15 is GREAT stuff,...just don't get any on you or you'll wear it for a week. About 14 years ago I painted the underside of my small trailer with POR-15 and it's still holding up like new (the trailer stays outside in the weather year round since I painted it too).👍👍👍