tank de-rust

[Kelly E]

I use EvapoRust and rinse with diesel. The last thing I am going to put in a freshly derusted tank is water. When you dump out the diesel into a jug let the sludge settle and pour the diesel back into the tank for another round of rinsing. I rinse at least 4 or 5 times. Never have had any flash rust with this method. The diesel can be used over and over again. Just keep pouring off the clean diesel and dump the sludge.

De Ionised water is just fine, it's very cheap, readily available and prevents flash rusting. Then swill round with diesel.

Why add a step you don't need?

[mickwinf]

so here is the problem, different people have used different methods with some success but none so far have worked well for me. The phosphoric acid is supposed to leave a rust resistant surface but needs flushing out, and as its presumably mixed with water anyway surely water flush is the answer. will keep trying.

[Kelly E]

so here is the problem, different people have used different methods with some success but none so far have worked well for me. The phosphoric acid is supposed to leave a rust resistant surface but needs flushing out, and as its presumably mixed with water anyway surely water flush is the answer. will keep trying.

I've derusted a bunch of gas tanks with EvapoRust and a diesel rinse. Never had a problem with flash rust coming back.
This 70' CB450 DOHC gas tank was all rusty inside. I filled it up to the top with EvapoRust and left it for a few days because the EvapoRust was used a few times already. I diesel rinsed it and it's been empty for over a month. Still nice and clean.

[mickwinf]

I have had success with this now, used the rust remover then washed out with de ionised water, then dried out with a hot air gun. Then swilled out with diesel and left for a few days, just checked and it seems to have worked.

[matthewmosse]

Would anyone have tried or could say whether perhaps electo plating or anodising might be an option? Say if one were to use the tank itself as both the vessel and electrode and either zinc or copper coat it? Is that feasible?

[K2-K6]

Anodising process for alloys of aluminium generally,  controlled surface corrosion within treatment baths that then make it resistant to deterioration unless scrathed or damaged.

Ferrous base material plating,  thoughts are that copper and copper alloys aren't fully resistant to ethanol and may not give a fully resolved solution.  Zinc potentially more useful and not originally done by manufacturers for cost reasons,  probably right as they've essentially outlasted any service life prediction at a guess.

Enquiry to platers regarding logistics of tank internal may yeald a practical path.