Rusty fuel tank fix

[suzuki27]

I've got  some flaky rust inside the tank on my XL250. Can anyone recommend a good way to treat it?
 I've been looking at the kbs and por products. Are these the go?

[80-85 husky]

I used to get a heap of nuts and bolts and wack em in the tank and then chuck in soapy water and do the cha cha  for a while give it a good flush out and it should be ok. if its really rusty like nearly holey then you need to look at those sealing products such as por. ive seen good results with them but preparation and instruction following is vital

[Branchy]

crusher dust (very small sharp blue metal rock) with a solution of sugar soap and hot water , then do the POR fuel tank treatment.cheers

[Momus]

I've just cleaned up the inside of a very rusty '74 CR125 tank with the time honored molasses method.

I filled it with 2 parts water to one part molasses mix and let it sit for a few days.   
Gave it a hot water rinse and sprayed a bit of CRC inside and dried it with a heat gun.
The tank interior is now mostly bright metal with no signs of active rust.

Molasses eats the rust but has no effect on the sound steel.

You can buy molasses from a feed store; I paid 12 bucks for a 5 litre pail.

[pokey]

The best method ive found for rust (and i do find some very crappy units) was  told to me by an old cow cocky many moons ago.

Fill the tank with a mixture of 4:1 or 5:1 water and molasses. yes that sticky black sweet stuff. Golden syrup wont do.

molasses has chelating properties(Greek for chisel)
It will lift all the rust off leaving good metal behind.
 Unlike acids that you will fins in the Por kit it will not harm good metal.
 chuck a few old nuts and bolts in just to help out .
 leave the solution in for a week and give it a shake once a day but do note that you will have a bit of pressure build up.
rinse it well with water and then metho to get rid of the water and 2 stroke oil as it will flash rust almost straight away.

 After this you can put the POR liner in if you want to go down that path. Do not that sometimes rust goes all the way through and you may need to fix pinholes.

I have one of those plastic tubs  filled with a brew that i chuck my steel bits in all the time.

[80-85 husky]

go the molasses!!  id forgotten about that.....

[Nipper]

Can vouch for the molasses treatment ,did it myself on my TM tank last week worked a treat !

[Andrew L]

I haven't tried it myself but some have said fiber glass resin works well inside a tank after the rust is treated to seal it up, has anyone tried it? Cheers Andrew

[Branchy]

http://www.ppcco.com.au/por18.html

[OverTheHill]

Molasses!!, got me worried now. Saw it on the supermarket shelf last week thinking--we used to give that to the cows when i was a kid--so bought it. Had one big spoonful. Should i be worried?. Reminds me of cleaning my B33 crankcases back in the early "60's. Found the caustic dad put through the milking machines with boiling water after every milking reacted with the ally [learning] So dumped the cases in a big bucket of a heavy mix & let it go [went mad], cases went black & had to solder the bearing outside as were loose in the cases, sounds rude but worked. Won't mention my LTF300 head i put in the log fire to burn 30 years of crud off & pulled out two valve guides & two valve eats. Damn--slow learner. At work a customer had done the 'tank sealer' thing with his XZ550 twin & the stuff had gone right through the twin downdraft car type carbs & was a major headache was that one. Anyway---.Mooolasses.

[suzuki27]

Thanks guys. I will give a molasses a go.

[Paul552]

Thanks guys. I will give a molasses a go.

Do us a before and after pic.

Love to see it.