Rusted gas tank

[tfair]

Well I finally did it, I pulled the 1973 Kawasaki 125cc out of my mother in laws shed where it has been for the last 20 - 25 years. It is a mess but I figured I will start with the obvious and go from there. The gas tank is coated in rust on the inside and I am looking for feed back from you guys about the pros and cons of the diffrent methods. I have seen several ways of doing this including Freebirds post on Kleen. I figure either way I go I will be putting washers, chains or some other metal in there with a good spin to loosen up all the surface rust and break loose all I can before going with the chemical cleaners. Someone suggested tieing the tank in a blanket with washers in it and putting it in the dryer on NO heat for some time to get it all knocked loose.

 

What are your thoughs on the following methods:

 

1. Navel Jelly

2. Kleen

3. Electrolosis

 

If you have another idea I am all ears. I want to know which method you think is best and more importantly in my case idiot proof.

[nelsontoddpa]

Any thoughts on taking it to a radiator shop and having them do their magic? A friend of mine took a rusted gas tank off an old snowmobile took it and they boiled it with some chemical, and it came out as good as new.

 

Just a thought.

 

Todd

[KiteSquid]

I would probably try the electrolysis method, but you probably will have to coat the inside of the tank anyway, so buy the kreem....

[Guest timshosvt]

I've had good luck with Yamaha's Fuel Tank Rust Remover. $14.95 for both bottles at Yamaha shops. You may have to search a bit, as it's been discontinued. It's a two part kit, with part A being a pint of phosphoric acid and part B being a sodium metasilicate solution (absorbs any remaining acid and dries out the interior). To use, you remove & drain the tank, seal the bottom openings, then fill it half way with water. Add the phosphoric acid and top off the tank with more water. Cap the tank and agitate. I used a length of chain and some nuts on a length of wire. (I don't know if I did a bad thing by using zinc plated chain and copper wire) My brother bungee'd his to the bed of his pickup and drove around for awhile...I just shook mine periodically, then power washed. Wear goggles as you are using acid and pressurized water.

Remove gas cap (to vent), and let sit for four hours . Drain, rinse (a pressure washer is recommended), repeat drain & rinse operations several times . Then pour in part B, and agitate to coat every nook and cranny. This will absorb any remaining moisture and any remaining acid. Drain and allow the tank to air-dry completely. The sun helps. I filled mine with fuel right away...Didn't want to take any chances.

I wonder if you could just try some concrete cleaner, nuts and bolts, agitate, power wash, rinse, etc. and get the same effect.

 

Good luck,

Tim

[AZSpyder]

I have been using Muriatic acid mixed down with water. It will eat the rust and not touch the solid metal. Usually I eye ball 10 to 20 percent acid. After rinse with lots of water. The hard part is getting it dried out before surface rusting. If there is gas varnish in the tank I use Lye or Lye based drain cleaner first. The lye will remove any organic matter, the acid won’t touch it so also can’t get to any rust under varnish.

Jerry

[utadventure]

I just ead about a product called Red-Kote. It looks interesting but I don't know about availability.

 

http://www.ftrs.com.au/fueltanks/red_kote.php

[hipshot]

I have been using Muriatic acid mixed down with water. It will eat the rust and not touch the solid metal. Usually I eye ball 10 to 20 percent acid. After rinse with lots of water. The hard part is getting it dried out before surface rusting. If there is gas varnish in the tank I use Lye or Lye based drain cleaner first. The lye will remove any organic matter, the acid won’t touch it so also can’t get to any rust under varnish. JERRY

 

a "tip" on muriatic acid use.

after you clean the tank with muriatic acid, flush with clean water, then wash/agitate with a really strong mixture of BAKING SODA and water. the soda neutralizes the acid left in the pigments of the metal.

 

 

 

 

just jt

[Guest Popeye]

Last May, I had rust in my tank & saused my 86 VR to quit.

I drained tank into a white pail & saw black silt [rust].

Bike ran 13k with zero problems & BLAM, carbs stuffed with rust?

 

Shop rebuilt carbs, washed tank with sulfuric acid [don't know %] & relined with a very thick white liquid. My rust was very minor & option of a used replacement tank was $350 [if available].

Acid only works for very minor rust.

For serious rust, the rust must be removed mechanically, before relining.

 

I use muriatic acid for cleaning brick/mortar on my house, to clean my stone fireplaces & concrete driveway.

 

Antique restorers have the rusted tank sandblasted inside with aluminum oxide, then coated with a sealer that needs to be baked on. One place I found charges $300-$400 for the job.

 

Older bikes with low mileage are scary.

[Vance]

I have a friend who said he filled a rusted gas tank with motor oil, and let it sit, intending to clean it out later on and coating the inside. He thought the motor oil would prevent further oxidation. When he finally got around to draining out the oil, he was amazed at how clean and shiney the inside of the tank was. The oil had dissolved/removed all the rust! I haven't verified this works, but thought it might be worth passing on.

[zagger]

Someone suggested tieing the tank in a blanket with washers in it and putting it in the dryer on NO heat for some time to get it all knocked loose.

 

 

I love the dryer idea, hope it is a cheap one and your wife is out of town! I blasted some rust out of a tank with a pressure washer and used red coat to line the inside. The red coat stuff is a pretty nasty concoction made of methyl ethyl ketone and some plastic stuff. Sort of like molasses and pretty hard to get into every corner. Thinning it with some more MEK helps but it is still pretty goooky. Once it hardens (filling your lungs with MEK vapors) it seems ok - kind of a plastic coating. Best of luck.

zag