Tank Rust - Phosphoric Acid

[watchhislegs]

Has anyone tried to use phosphoric acid to remove rust from a fuel tank? I looked into electrolysis but iI don't trust myself; something will go wrong!

I have a litre of 82% phosphoric acid and it can be watered down. Tried it neat on a rusty sprocket and it demolished the rust in about ten minutes.

Thanks

Nico

[JonW]

Gary, can I ask how long you left it sizzling?

[Norbo]

Never used it my self but i all so have half a litre in the gararge so i may give it a go on the next tank thats rusty just to see how it gows.

[JonW]

LOL, yeah thats what i planned really. Having had to leave the gearbox parts in the vinegar for weeks to get rid of the rust I was thinking with the thinner steel of a tank it might not need as long.

Interestingly I have a KBS coatings version of POR15 tank sealer kit and that has the phosphoric acid in it as one of the stages. looking online it seems you do that stage as long 'as needed', LOL

[watchhislegs]

You can get phosphoric acid pretty cheap on ebay. I went into a garden centre to try and get some and I think they thought I was some sort of geordie terrorist (like Raul Moat on a grander scale). I'm not kidding you when I put it on this rusty sprocket it kicked the shit out of the rust, it was bubbling off.

It would be interesting to play around with the dilution of it as it might be a bit better than vinegar. I was boiling a master cylinder in the kitchen the other day and I chucked a bit of balsamic in there; it made the house smell like an old man's nappy.

I was planning on giving it a quick wash with diulted bicarbonate of soda and then finish it off with a swill o' meths. Then drying and getting the POR in there.

Any thoughts or potential hazards in this approach?

[jonno]

Yeah,

Careful you don't pick up a "Meths" habit! ;D

[watchhislegs]

It's pretty cheap is meths; just mix with milk and imbibe. It takes the edge off the day.