Acid cleaning of gas tank

Hi All; I can't seem to find the thread by OKC_Kent documenting the process of acid cleaning. I get the dreaded 404-file not found. I've got a tank that was Kreemed a few years ago and it now has some rust. I'm thinking of dissolving the remaining Kreem with MEK or Acetone and then using the acid to remove the rust. (Shame on me for letting my bike sit unused) Thanks and ride safe, Steve

Two other methods (alternative to acid) which might also be considered (after removing Kreem).

(1) Electrolysis. Thereafter, flush tank interior with water, then rubbing alcohol, then WD40.

(2) Load empty tank with B-Bs, chain, nuts and bolts. Put tank inside clothes dryer, padded with pillows, blankets, etc. so tank is immobile inside dryer. Run dryer on no-heat setting until interior of tank is polished clean. The ferrous items are easy to remove, using a magnet if needed, whereas sand or pebbles, etc., are sometimes more difficult to remove. Flush tank interior with water, then rubbing alcohol, then WD40.

Good Luck!

P.S. EDIT -- Of course, do NOT use any acid in the clothes dryer method.

Hey thanks for looking for the writeup, I'm glad someone finds it useful. I have the link here, it's still in the Filebase.

kzrider.com/index.php?option=com_docman&...d&gid=248&Itemid=108

I heard acetone will dissolve Kreem

Good luck!

OKC_Kent wrote:

... heard acetone will dissolve Kreem....

Acetone does indeed readily dissolve the old Kreem coating inside the tank.

Be exceedingly careful to prevent acetone from contacting the exterior painted surface of the tank.

Acetone will very quickly -- sometimes instantaneously -- ruin a painted finish.

Sorry, don't know squat about MEK.

Good Luck!

If it is flash rust I use white vinegar(cheap) to remove it. Cheap and works good but it does etch the tank so flash rust will appear again very quickly. The residu will mix and burn with the gas but I get out as much as possible without doing backflips. Plus when you pass people they skedaddle to the closest McDonalds and buy some fries. :ohmy:

Check out:

Rusty tanks.
That's an adjective and a plural noun as opposed to a name and a verb.:laugh:

If you use the WD-40, flash rust is a thing of the past.

KZCSI

Acetone and MMEK are pretty much interchangeable, as far as their uses. I like to use MEK because it doesn't flash as fast as acetone. Either one will dissolve the Kreme.

Phosphoric acid is the product to use to eat up the rust, although, I have found that it is unnecessary if you use my method to coat the tank. If you have used any kind of oil, kerosene, wd-40, etc. to coat the tank it will have to be washed out with gasoline or paint thinner or MEK.

Use epoxy, not polyester, resin to coat the inside of the tank. You can thin it with acetone or MEK to make it easier to coat the tank. Just tape up any openings and rotate the tank until it is completely coated. Pour out any excess and let it cure.

Steel cannot rust without oxygen. The epoxy will encapsulate the rust and any other small particles of trash in the tank and leave the interior as smooth as a baby's butt.

I know that this method will generate some controversy, mostly from people that have never used epoxy, but I have tanks that were treated this way, one over ten years ago, and have never had any problems. One was a tank on an old jeep pickup. Another plus is that the epoxy will seal up any pin holes.

Thanks,
Robert

Gents; My humble thanks to Patton, OKC_Kent, Locozuna, KZCSI and saltydog for taking the time to help me out. I'm a complete ass for letting my Z1 sit for years without checking out the tank. The Kreem job I did held up for a few years but just couldn't stand up to the condensation. I now have the benefit of others experience and that's about as good as it gets. Best regards and ride safe, Steve

What do you advise to just remove varnish from a tank thats been setting without damaging the perfect original paint ? In the past Ive had tanks boiled out at radiator shops then they coat them right there, but it removes all paint too. Thats Ok if you plan a repaint, but I dont. Thanks for any help on this.....Woody

Any special kind of epoxy? I have a tank that needs sealing and it has a couple pin holes in it.....chris3

saltydog wrote:

Use epoxy, not polyester, resin to coat the inside of the tank. You can thin it with acetone or MEK to make it easier to coat the tank. Just tape up any openings and rotate the tank until it is completely coated. Pour out any excess and let it cure.
Thanks,
Robert

This may be the dumb question of the day, but do you mix a hardener in the resin?

I did more searching on epoxy lining and found this from Caswell. Looks good to me and they tell you to use acetone or lacquer thinner to get rid of the old gas.

www.caswellplating.com/aids/epoxygas.htm