Removing rust in a mc gas tank.

[artmusic247]

Aloha,
What's the best way to remove surface rust inside a motorcycle gas tank?
Thanks, Dean.

[sswee]

I usually use muriatic acid, like they use to clean cement. You have to be careful. If you don't use a tank sealer it go right to rust in no time. I'm pretty sure Caswell has a tank sealer. SS

[pickleboy]

hey sswee it that to say that muratic is good for derusting all steel. if so at what concentration? i am doing an old gas pump and the frame work is rusty and i dont feel like taking all the time it will need to blast it from rust to clean. if i can derust it first it will speed the job up.
artmusic247 sorry i am not meaning to highjack your thread but i have heard of this before and was curious. also when you are done you should reseal the tank with http://www.caswellplating.com/aids/epoxygas.htm or kreem gastank sealer.

[sswee]

I have only used it on fuel tanks but I don't see why it wouldn't work. I'll have to check the jug to see what concentration it is. I use it straight from the jug. I buy it at a local farm supply, but I've seen it other places in a white one gal. jug. SS

[artmusic247]

Thanks for the advice. You people here are very polite, pickleboy.
sswee, you said you bought muriatic acid at a farm supply store, what are farmers using muriatic acid for? Are there other places where they would sell it?
Thanks, Dean.

[seanc]

Guys:

Muriatic acid does dissolve rust. It ALSO dissolves steel! While it dissolves rust hundreds (?) of times faster that steel, you have to monitor it closely so it doesn't eat to much raw steel.

I blew it once. Had some small surface-rusted #4 & #6 nuts, bolts & washers, so I tossed them into @ 20% solution, then proceeded to forget about them for more than 2 days. The washers had disappeared entirely, and the nuts and bolts were unrecognizeable!

Muriatic acid is just dilute Hydrochloric acid. I don't know what the ratio is off hand, but it's still fairly strong. The plating manual recommends 2 or 3 different "pickle" concentrations for removing light rust/medium rust, etc.

I use a 5% concentration as a final pickle just before plating a part. That way I KNOW it's rust-free.

It's available in normal hardware stores, and is fairly cheap.

Sean

[sswee]

That was the part where I said, you have to be careful. Maybe I should have clarified. Any chemical should be monitored carefully when in use. I have left hanging wires in anodize stripper to clean for reuse, gotten side tracked and come back to nothing but little pointed pieces no good for anything. The muriatic acid needs to be applied, left usually for only 2 to 5 minutes, rinsed well and checked. It is like working with alot of other substrates, better to go a little at a time than to go too far. SS

Most hardware stores, masonry supplies carry muriatic acid.

[jimcarry]

To remove Chrome and Rust
first you will need a tank large enough to hold the part a piece of stainless steel size depends on the part you are de plating a power source battery charger will work
there are different type of Acid Pickles they are explained in greater detail on pages 34 35 and 36
of the Caswells Plating Manual
WARNING ! Never pour water into Acid always pour acid into water
Pickle 1 used for mild etching before plating
to make this solution
20 parts fresh water to 1 part muriatic Acid for etching soak part for 1 to 15 minn 1 hour will remove rust from most steel

Pickle 2 also rust remover and de- plater
to make
2 parts fresh water 1 part muriatic acid
to remove Chrome hook you positive lead to you part and your negative lead to the stainless
adjust your power to 1 amp per sq inch de-plating should be complete in approx 15 to 20 minn
DO NOT use this method on Pot metals or aluminum !!!!

[mpierich]

Originally Posted by artmusic247

Aloha,
What's the best way to remove surface rust inside a motorcycle gas tank?
Thanks, Dean.

The Kreem kits have deruster, sealer and catalyst all in one kit. You put some nuts and bolts in with the deruster to help loosen up the rust (tip: make sure you use ferrous nuts/bolts so you can use a magnet to get them out if you have to - don't ask me how I know...).

[artmusic247]

I wish you folks would of told me that it desolves metal before I used it, I thought that someone stole my gas tank! Just kidding. I'm going to be looking around for muriatic acid this weekend. What kind of skin protection should I be using when working with muriatic acid?
Thanks again for the help, Dean.