Rusty Fuel Tanks

[bowewilson@gmail.com]

I am in the middle of cleaning and relining the steel fuel tank on my R66, thought I would mention where I am at and maybe you guys might have some thoughts.
The plan is to get the inside of the tank back to bare metal and then apply a coating of "Redcote".
Having had a look at various options on Utube I decided to run with treating the tank with Apple Cider Vinegar ( yes I was sceptical too), I wasn't keen on going down the path of hydrochloric acid and the like as I thought it might be a bit savage on the tank, the paintwork and me.
It was suggested that a tankful of ACV for two days would be sufficient, not so, I left it in the tank for four days and then flushed it out getting about 2/3rds of a cupful of gunk and rust, I would say this got about 95% of the rust out but there was still some staining on parts of the tank.
So I decided to get some crushed bluemetal and sloshed it around the inside of the tank for about 10 / 15 minutes to no avail.
Next step was to refill with a new lot of ACV and after 2 days it has done a pretty good job, so I will drain it in 2 days time and have a crack at the painting process, will report back in a few days to see what sort of a mess I have made.

[Goldie1]

Hi Bow I have read something about a molasses solution and let it soak for a while. I know it sounds strange but check it out on the net

[bowewilson@gmail.com]

Saw that, I thought I would start with the soft option first!

[RobBD]

Soaking for a while in a barrel of water with lemons will rip rust off. Molasses does work and I don't know the amounts though - the vintage car boys use it all the time. I haven't tried it yet but I have '22 Minerva Tourer that is also about to get the rusty fuel tank treatment - will keep you posted,
Cheers Rob

[bowewilson@gmail.com]

Late last week I emptied the Fuel tank of ACV to see a 99% rust removal job, probably would have been good enough to paint, however there was still a couple of small bits of rust on the bottom of the tank so headed off to the super market for some more ACV, by the time I got back (40 min) there was a film of light rust over the whole inside of the tank.
Couldnt believe it, so refilled with ACV and will have another look today or tomorrow only this time will have all the neutralising, metho and heaters ready to go to do the job quickly.

[bowewilson@gmail.com]

All done, managed to get the neutralising, drying etc done in about 20 mins, still had a small amount of oxidizing happening, not sure how to get around that.
Next step was to block off the fuel outlet and the fuel equalising outlets and pour in the Redcote (the lining material I used, a can is 900 ml) followed by a bung in the fuel filler, then proceed to toss and turn the tank until you are satisfied you have full coverage (the BMW tanks with the toolbox in the top probably need a bit more), stopping every couple of minutes to relieve the vapour pressue that builds up in the tank by releasing the bung for a second.
Next is to set up something for the tank to sit on inverted and drain the excess Redcote back into the can through the filler hole (I masked up the tank so I didnt get the Redcote everywhere), try and get as much out as possible to prevent pooling in the tank (I didn't quite get this right!), I used about 250 / 300 ml of Redcote, clean up is with Acetone.
Once the draining is nearly finished I got some 1/4 inch hose and and fitted onto the tank equalising tubes and blew through same to make sure there were no blockages of paint
Do this job in a well ventilated area as the Redcote stinks and I suspect could be explosive with the right conditions, I also used a hairdryer to warm the tank up to get the drying process happening, this also tended to dry the paint in situ rather than letting it pool.
As an aside I discovered a small crack in the tank that I was not aware of, small bonus!.

[goodguy]

An interesting learning experience is all this.

[bowewilson@gmail.com]

I managed to finish up with a small "pool" of Redcote on the bottom of on side of the fuel tank which is proving difficult to "dry", it is a difficult process to avoid this, particularly the BMW tanks with the inbuilt toolbox as it tends to drip long after the rest of the tank has gone off.
Will leave it for another week and see what it looks like.
The rest of the tank looks good.

[goodguy]

Simon landrie from Motorcycle panel & Paint in Osborne Park would be the man for tips upon this subject...I recall several years ago he mentioned it having to dry for "three weeks" after lining the tank with something.

[bowewilson@gmail.com]

Guy, yep not planning to fuel up for another 10 days, Redkote say whenever the smell of the acetone disappears, the gent your referring to I think some sort of two pak paint I think