Topic: Gas Tank Rust

[helgiman]

I have finally stumbled on to a way to de-rust a gas tank. I had a 79 DOHC tank that was completely covered with rust inside. While searching the net I came across a website called Theruststore. They have several products for rust removal. I chose Evapo-Rust. I emailed them to see what they thought about the application I intended to do. Got a reply from Rusty! Yeah Rusty. He said they have never had the product used in that way, but it should work. The stuff is not that expensive. $24.00 a gallon. I decided to go for the 5 gallon size which came to $99.00 delivered to my shop. First I poured about a pint of Castrol purple cleaner with a gallon of hot water in the tank and swirled it around for 10 minuets. Then dumped it out and rinsed with 2 gallons of hot water. Poured that out, reinstalled the petcock, and filled the tank with Evapo-Rust. Instructions indicate a soak of about 20 minuets should be sufficient for light rust. I had more than light rust so I decided to let it soak for 24 hours. The next day when i looked inside, I couldn't believe it. Nice and shiny, like new again. The solution was not discolored any more than when it went into the tank. So I put a hose on the petcock and ran it back into the pail it came in. Then I rinsed with hot water a couple of times. To get the rest of the water out, I took a piece of stiff wire and crimped a paper towel balled up on the end. Place that through the fill hole and dabbed up what I could. Next came the hair dryer. Blew that through the filler hole with the petcock off the tank for about an hour. The tank was good and hot after that! Seems to have worked well. Then I put about a cup of Marvel Mystery Oil in the tank and rolled it around to get a good coating inside. A couple of days later the tank was still looking brand new inside. I had sold the bike to a woman and she could not pick it up for a while. She was amazed at the results, as she had seen it before the treatment. The best part about Evapo-Rust is that it can be used over and over until it loses it effectiveness. I am still using the original 5 gallons on rusty chrome shock springs, exhaust collars and even some rusty tools.
Ed

[Aaron J Williams]

Did it hurt the petcock in anyway? It sounds too good to be true! Is it safe for paint? Any bad fumes/toxicity to worry about?

[GNXFan]

I've posted results about Evapo-Rust before. Great stuff. My son got me a 5 gallon bucket for Christmas and I've de-rusted everything I own practically. He got the bucket for $76.00 with his employee discount at O-Reilly's. Here's a pic of some 750 parts that have soaked in it. It not only will remove the rust but it also removes paint, but not very quickly.

[helgiman]

It says that paint and rubber etc will not be affected. I was very careful with the stuff getting on the paint, wiped it off right away. I just rinsed the petcock off in water and dried it with the hair dryer. The solution itself has an almost undetectible odor. There are no special handling instructions other than wash your hands after exposure. You can even pour the stuff down the drain when it is no longer useful. I'm very impressed!
Ed

[GNXFan]

Yes , it will not affect rubber. The oil tank and the battery box in the pic I posted had the rubber mounts still on them when I soaked them and it did not react with the rubber at all.

[Cvillechopper]

Do any of the chain auto part stores carry this stuff? 

[InaneCathode]

I use muriatic acid. Its something like 4 dollars a gallon at home depot. Pretty much cleans anything.
Does anyone here line their tanks? I do it almost religiously.

[GNXFan]

Cvillechopper, Autozone and O'Reilly's both carry Evaporust.

InaneCathode, I have also used muriatic acid and it will clean the rustiest of tanks in about two minutes the tank is clean. It will flash rust very quickly so once you start the process you're committed until it's done. I then coat it with Red-Kote tank liner, not Kreem.

[flipprboi]

i use muriatic acid too but i mix it with 4:1 water. Muriatic are strong and  will surely eat them rust away. Even good metal if your not careful. Then i use kreme's tank prep to avoid surface rust.

[eurban]

The Home Depot's here in MD are now carrying phosphoric acid in their paint stripping section.  Product is called "Prep and Etch." It is a gentler, more forgiving product than muriatic acid that takes overnight to work but leaves a rust inhibiting coating on the metal.

[InaneCathode]

Whatever you do dont mix phosphoric acid and muriatic acid, dont ask how i know that <_<

I use POR 15 when i line my tanks. Its cheap, works very well, and doesnt break down like kreem does. (Who still uses that crap anyway?)

[prince_ruben]

+1 on the Evapo-Rust. Best thus far.