Rust removal from fuel tank?

[Enzo200500]

Got a customer bike in that had been sat for a few years with stale fuel festering away.

We knew the fuel pump assembly was beyond hope, as it had seized solid. You can see where the level of petrol was in the tank…

 

Yep, it’s fuckered…

 

I have ordered a genuine pump unit from Kawasaki, £532!

But, what is the best way to remove the rust that has built up inside the tank? It’s not rusted through anywhere, but we really want to save it, if possible. A new one is £950 from Kawasaki….

Anyone know of some nasty chemicals or is it the Electrolosis method?

[noely02]

https://club.autodoc.co.uk/magazin/how-to-clean-rust-out-of-a-motorcycle-gas-tank

Vinegar: you will need enough vinegar to fill the entire tank. The type doesn’t matter, white or apple cider vinegar is fine, as this only depends on the acidity of the liquid. Take a brush (the type you might use to clean a bottle or large glass) and brush and swish it around the tank to loosen the rust. You can now let this sit for up to three days for optimal rust removal. After the three days, drain the vinegar and debris, and fill it again with clean water mixed with a box of baking soda. This will help to neutralize the acid. You can flush it out with diesel or petrol, or use a heat gun to heat-dry the inside. 

Citric acid: this can provide great results, and you can buy this in most supermarkets or online. Put about 400 grams into the tank and then add boiling water, making sure you fill it all the way to the rim. Now let it sit for about 24 hours. After 24 hours open and empty the tank, using the same procedure as in the vinegar method.

Cola: this is perhaps the most uncommon of all. Fill the tank with any kind of undiluted cola all the way to the edge, and let it sit for 24 hours. Then follow the same procedure as with the citric acid to empty, clean, and dry it. The result is better than with citric acid, because the phosphoric acid contained in cola also seals the tank at the same time. Moreover, phosphoric acid is also contained in standard tank cleaning kits.

[Enzo200500]

Great information chap, thanks!

[noely02]

i'm going to try the citric acid method on the deek when i get round to it, it work wonders on my crappy Worthing water crudded up kettle  

[426hemi]

I used the rust remover that Por15 sell, did a great job. It’s called metal prep and is reusable.

[dansp1]

I stick by what I've said every time this topic comes up, Bilt-Hamber

[noely02]

41 minutes ago, dansp1 said:

I stick by what I've said every time this topic comes up, Bilt-Hamber

this stuff?

https://bilthamber.com/product/deox-c/

 

[dansp1]

Yep, it needs pre treating with their de greaser and they do a fogging spray for post treatment now i believe but it's fantastic stuff

[hawkati]

i was advised white vionegar & salt and give it some shakey every day for a week, then deionised water & biocarbonate of soda to neutralise it. I cheerfully used a litre or three of unleaded just to rinse it all out and the tank is almost clean as a whistle. 

[Ray Von]

On 7/7/2024 at 3:22 PM, dansp1 said:

I stick by what I've said every time this topic comes up, Bilt-Hamber

I used this on my RGV restoration, a tank not seen fuel in 20 years. 

I've gone through 3 tanks of fuel since back on the road, pulled all the fuel filters (tank, in line & the carb filters) just the usual grains of dust in there. 

Worked for me, think 1 bottle does 20 litres when mixed. 

[dansp1]

1 hour ago, Ray Von said:

I used this on my RGV restoration, a tank not seen fuel in 20 years. 

I've gone through 3 tanks of fuel since back on the road, pulled all the fuel filters (tank, in line & the carb filters) just the usual grains of dust in there. 

Worked for me, think 1 bottle does 20 litres when mixed. 

Yup and you can keep reusing it until it's turned black and stops working

[Ray Von]

6 hours ago, dansp1 said:

Yup and you can keep reusing it until it's turned black and stops working

True, I did a spare rgv tank I had lying about too. 

Plus some tools that had gone rusty to see what happens, seems to remove the rust and put some sort of coating which went black. 

Definitely works a treat

[Mr.Incredible]

Another vote for simple white vinegar. Really cheap from the local supermarket. I didn’t add anything to it; I just filled the tank with it and left it. It did an amazing job on a very old, rusted to fuck tank that had been left half-full for years. 

[TLRS]

As for drying it afterwards.. sticking a vacuum cleaner on it might help ventilate. Just as an alternative to heat.

Edd China made a small pool of rush remover for a car chassis. Might be worth a view as well, it's on the tube of you.

[Thunderbolt]

I use white wine vinegar.

If only there was a Chemist on the forum @Alpinestarhero?

[Alpinestarhero]

36 minutes ago, Thunderbolt said:

I use white wine vinegar.

If only there was a Chemist on the forum @Alpinestarhero?

Vinegar is ok, but one might find things better with a solution of lactic or citric acid. 

 

A very dilute phosphoric acid would also work very well (coca cola!). 

 

Best thing to do is start off with something mild (so, vinegar, which is ~5% acetic acid) and then try other stuff. And it helps to make the solution warm, and to agitate too. Keep in mind, though, that the acid will etch all the metal, so post-cleaning treatments will be needed. 

 

For post-cleaning drying, I would rinse with methylated spirits several times. The ethanol (and methanol!) that is left afterwards will evaporate much easier than water. 

Edited July 10 by Alpinestarhero

[Evilchicken0]

Blit and Harmer 

Fill the tank over half full  leave it overnight. Put 2 rolls of bubble wrap under it when you turn it over so the paint doesn't scratch and the mixture can drip through the lock on the filler.

Dry it out,I stick kitchen roll on a stick to get any standing water out then heat it with a hair drier (I don't have an airing cup.

Put oil / petrol mix in and tumble it if I'm not going to use it straight away