Gas tank varnish

[Tom Wesenberg]

Originally Posted by FRANK PKNY

The e85 took all the paint off my gas gauge. ate the cork gasket out of the fuel gauge also.

Good point about the paint on the gauge. Best to remove it and make a blank off plate.

[Dodge]

Denatured alcohol is the solvent for varnish which is what you have in your tank. I have used it to remove the crud in gas tanks. It takes awhile and you have to keep turning the tank.
When that gets every thing loosening up you can dump it out and put apple cider vinegar
In it and do the same thing. When that gets everything really moving flus it with hot water.
My 2 cents.
(If I put in my 2 cents and someone gives me a penny for my thoughts, someone is making money on the deal...)

[midgetracer]

I finally got the pickup home and the tank removed. It is worse than I thought. I pressure washed about a gallon can of solids...some large chunks and lots of flakes. I could see rust and some of the turne coating in the tank. I went to town to get POR 15 Marine Clean. It has changed names to Cleaner Degreaser. It has been in the tank for 3 hours and has turned brown(1:1 mixture with hot water). No real clean up of the varnish. I am returning to town to get Lye if I can find it. If not I will try Drano as it is lye with Aluminum chips. Wish me luck as the Radiator shop is too backed up to take on new projects. What is the group feeling on using a sealer. I have a can of Bill Hursch sealer. I would use metal prep (Phosphoric Acid) and dry the tank before using the sealer.

[BRENT in 10-uh-C]

Originally Posted by midgetracer

I finally got the pickup home and the tank removed. It is worse than I thought. I pressure washed about a gallon can of solids...some large chunks and lots of flakes. I could see rust and some of the turne coating in the tank. I went to town to get POR 15 Marine Clean. It has changed names to Cleaner Degreaser. It has been in the tank for 3 hours and has turned brown(1:1 mixture with hot water). No real clean up of the varnish. I am returning to town to get Lye if I can find it. If not I will try Drano as it is lye with Aluminum chips. Wish me luck as the Radiator shop is too backed up to take on new projects. What is the group feeling on using a sealer. I have a can of Bill Hursch sealer. I would use metal prep (Phosphoric Acid) and dry the tank before using the sealer.

Hate to be the 'Debbie Downer' but the Lye (Sodium Hydroxide) is really not going to do anything for you at this point. It only dissolves the organic matter, --which rust is not. If you are seeing some flakes, then there are other areas where the flakes have not released yet. The Phosphoric will only treat what it can easily get to, but to do the job correctly, you are going to need to remove the flakes of rust that are still attached. Hopefully pressure washing will get them however generally speaking, you can only get between the two baffles and not on either end which will likely have more flakes.


As far as sealers go, once the metal is bare (no longer coated with the Terne coating) then it will need to be sealed. My experiences have been that you need to avoid the Hirsch sealer.


.

[midgetracer]

Brent, what sealer do you recommend if the Hirsh is not good?