Flash rust in gas tank after cleaning!!!

Well I did some searching and found a good way to clean my gas tank (Muriatic Acid) I diludeted it very little and after about an hour I rinsed it out and flushed the tank for 20 minutes with water...



Well it looks like there is a significant amount of surface rust now.

What to do? thanks at advance

 

You might go back with some muriatic acid and then wash it out with soapy water, it shouldn't flash rust then.

 

sand and re-apply again. when you go to rinse, if liquid beads off it, youve done it wrong.

 

http://www.kbs-coatings.com.au/KBS-RustBlast_p_9.html

This stuff leaves a finish that looks like galvanising. No flash rust for up to about a month.

 

Rocket8
What ?????

 

Since you said "rinsed it out" I'm assuming the inside. Get some POR15 tank sealer. Work like a MILLION BUCKS!!!!

 

Ok looks like im gonna have to pick up the POR 15 stuff. Just wondering if I did t wrong?

Thanks fellas

 

Soapy water.

 

After you acid clean it, then rinse with baking sode water mix, then soapy wter to final clean, then put in a little diesel fuel and slosh it aound, the oily fuel will coat the inside if the tank and keep it from flash rusting, then as you run gas in it it will keep a light ioly coating on it, I have done that several times with no issues.

 

use phosporic acid instead..it leaves a residue and converts the outer layer to a non corrosive thin layer..as long as its not scratched, it shouldnt rust.

 

The same company that makes the POR-15 makes a product called "Metal Ready." It's a cleaner that I used after I washed out my gas tank with muriatic acid and it was able to take out the flash rust. Then after it dried out I coated it with the POR-15 tank sealer.

Thanks!
Tom - Glass_Packs

 

I used evaporust in my tank, then ran a couple tanks of 10% blend ethanol through it thinking it the alcohol would help keep the condensation down, so far so good.

Brad

 

Better yet, use the dilute muriatic acid (aka hydrochloric acid) like you did, rinse, then immediately use phosphoric acid. The muriatic acid will actually remove the rust whereas the phosphoric just passivates the surface. That one-two punch will get rid of everything. Most autobody water based 'metal prep' solutions are phosphoric acid based with additives and surfactants. Keep adding fresh solution to the tank and keep sloshing until the tank is clean. Be patient. Once you use the metal prep and slosh it around enough you should be able to rinse with water 3 times (preferably distilled, or better yet, deionized water) and remember to dry the tank out ASAP and keep it dry.

-Bigchief.