I have a old dirtbike and a honda 13 horse power washer motor with rust in the tank.Does anyone have a suggestion on how to remove it?
Thanks
Fat250

 

Go to a motorcycle shop and they can order a kit that will clean it up and coat the inside. The kit is based on capacity so you have to know how big the tanks are. You might need more than one kit.

 

Thanks ill call the bike shop monday.

Fat250

 

If it's just surface rust you can pour a little Muriatic acid into the tank and CAREFULLY slosh it around. It eats rust away like magic. I've cleaned up rusty oil pans and valve covers with it, not to mention old rusty flywheels.

If it's really bad, it may take a few applications. Wear a respirator and long rubber gloves. The fumes are STRONG! And, it will burn (Hey, it's ACID!) After you carefully pour it back out of the tank, neutralize it by flushing the tank with water and then immediately flush out the tank again to remove the water, this time you could use alcohol. (No, leave the Jim Beam in the liquor cabinet. Denatured alcohol should be fine.) I haven't actually used the alcohol before, but since alcohol has an affinity for water, it occurs to me that it should do the job. You could just go straight to flushing the tank with gas diesel, kerosene, or solvent.

If you have compressed air available you will want to blow out the tank to dry it and remove the remnants of any liquids, but you'll need to get fuel in it pretty quickly as bare metal stripped with Muriatic acid attracts rust. I've seen something stripped with it have a light coat of rust the next morning, even while having been in the shop overnight just from the moisture in the air.

If you find through this process that you have holes rusted clear through the tank, then you can use the fuel tank sealer mentioned above to seal it, and it will have a nice clean surface to bond to. -TD

 

here ya go

http://www.ripper1.com/tech/rust.htm

 

Drop some chain, bolts, and nuts in it. Fill it with hot soapy water and shake it for a prolonged period of time. Remove the liquid and chain/bolts/nuts and inspect.

 

Ok, I'd like to point out some safety issues here. Do NOT mix alcohol and acid. I work with a plating system and that is one of the safety rules we have. Since the plating tanks have acid with a ph near 0, it's about as active an acid you can find. I've been told the acid reacts with the alcohol and releases a flammable gas mixture. There may be enough heat released in the reaction to set it off.

Also, rinsing the tank with water will not neutralize the acid. It will dilute it. To neutralize it you will have to add a base to the water (baking soda comes to mind). Do not mix a baking soda with full strength (or large amounts of) acid in the fuel tank.

Now, from a practical standpoint, rinsing with acid and then diluting with water, and then chasing the water out with alcohol may be safe enough. Just be aware of any dangers if you may encounter. Wear gloves, eye and face protection.

 

Okay, thanks for the clarification. I knew someone would come up with some better advice. Generally, when I have used Muriatic acid to de-rust something I flush the part with LOTS of water afterwards, and then blow dry the part with compressed air. The alcohol came to mind as a way to remove the water from the tank, since it's enclosed and not as easy to get the rest of that water out of afterwards. I was in no way suggesting to add the alcohol directly after the acid. -TD

 

Use lye to get old jellied gas out. Sometimes the old dried gas looks like rust. The acids will not get it out very well. I have had to use lye (Red Devil Lye Drain Cleaner) and muriatic acid to finally get some tanks clean. Looked like brand new. Don't use lye and acid together.
Lye is great for cleaning dirty carberators too. Just got to be quick. It will eat the aluminum up real quick----no more carb!!!!
Lye and acid are real hard on hands and clothes. wear rubber gloves and old clothes. AND WEAR EYE PROTECTION!!!!!!!!
Be careful and good luck

 

That's true. I've suffered worse burns with alkalides than acids. The alkalides are slimy and will stick to the skin worse (think soap, it is a mild alkalide). Wile on your skin it will dissolve the natural oils (like you want it to do in the gas tank) and your skin will disintegrate. I would assume that if you get it on you, you could try to neutralize it with a mild acid like vinnegar.

The Red Devil drain cleaner is 100% pure lye. There have been news reports of people blowing up their plumbing or burning themselves with it when it spits back out of the drain. This happens when the stuff mixes with other chemicals in the drain pipe and then reacts (sometimes violently). The funny (scary) thing is, you can pick this stuff up in any grocery store. So some people may assume it's strength is comparable to other consumer grade stuff.

 

Thanks everyone,

I have acid and lye and will try acid first with the nut and bolt method.Theyy al make sense.Its got to be better than running for fivr minutes and then cleaning the carb again.

Thanks
Fat250

 

Find someone who has a shaker parts cleaner. I have one in my shop, it is filled with rocks and simply vibrates. Just put a few rocks and some solvent in the tank and start the cycle. The tank will come out as good as new without any harsh chemicals.