Cleaning inside of fuel tank.

[SpitfireGeorge]

Hi Guys,

My fuel tank has been cleaned and painted externally but it is quite rusty internally. Anybody got any recommendations on how to remove the rust and crud prior to fitting it to my Spit Mk3? I assume the sender has to come out prior to the clean, what is the best way of removing it? I can see the lugs should I use a block of wood and hammer to unscrew it?

Cheers,

Brett

[Paul H]

I used Por15 tank kit from Frosts for my Vitesse tank . Worked well and 3 years on all ok but follow the instructions to the T . To remove the sender a block of wood with a hammer should be fine . 

Paul 

[DanMi]

I used the same por 15 kit on my spit. though I also put some gravel in whilst using he marine clean and phosphoric acid and rattled occasionally to aid cleaning. It was a pig to get it all out! but still good 9 years on

 

[Pete Lewis]

Any tool that  allows  a light  tap on then  lugs will  turn the ring to release the bayonets

There special tools  out there but not  really needed

Pete

[Badwolf]

I put a length of chain in mine attached to a piece of wire securely taped to the outside to aid removal. Can't remember what the inside was treated with, if anything. It was a long, long, time ago. Possibly some propriatory 'fix all' of the day. Still appears to be ok though.

[thescrapman]

I had seen a few cases were the internal tank treatment has started to come off and the continual blockages make the tank a write off.

fill the tank with loads of nuts and bolts and shake it about, or even better strap it to a cement mixer.

 Tape the filler up!

you could then fill the tank with an acid solution to clean any remaining rust out.

[KevinR]

Some of the tank internal treatments are not robust against modern fuels containing bio ethanol.

 

[Guest]

I have used POR15 fuel tank treatment and adding to the above comments, it is excellent stuff and works perfectly.

What I would say is that you need to follow the guidance to the letter for the process to work correctly. After the degrease and then the rust treatment I stored the fuel tanks in the airing cupboard for a couple of days between each step to ensure the tanks were Sahara dry. Each of the first 2x treatments require water to flush the products out, which seems odd when you have just used a rust inhibitor (!!) BUT you must follow the process fully for the operation to succeed.

PO15 fuel treatment is ethanol proof, but as Kevin rightly points out not all products are equal to that.

Shop around for the kit - I got mine from Demon Tweeks a few years ago, it was the best price then but may not be now.

Well worth the effort.

Good luck.

Regards.

Richard.

[Badwolf]

I have also bought Frost products from Demon Tweaks via fleabay for less than the normal Frost price also got it on a 10% off sitewide day.

[SpitfireGeorge]

Thanks guys,

I will give the POR15 a go.

Cheers,

Brett

[Paul H]

1 minute ago, SpitfireGeorge said:

Thanks guys,

I will give the POR15 a go.

Cheers,

Brett

Frosts sell 2 sizes and you will find your tank right in the middle, mine was for a vitesse. I rang frosts for assistance and of course they recommended the larger size which turned out to be too big. I did have another spare vitesse tank so did 2 . My guess is that you can get away with the smaller kit especially if the rust hasn’t gone all the way through 

Paul 

[JohnD]

Classic motor bike treatment is to put two handfuls of gravel in the tank, wrap it in a blanket and put it in a concrete mixer!    Modern equivalent might be a tumble dryer - when 'er indoors is out, naturally.    So Badwolf and scrapman are on the right lines.    A Spit tank is the wrong size and shape for that, but the idea is good, maybe if the work is shared between two, shaking the tank to and fro?

POR15?    I'd want to see the compatibility with E5/10 petrol.   POR make a fuel tank sealing kit, which should be more suitable, as the US has had E10 for longer than we have.     But phosphoric acid is cheaper, and ferric phosphate is almost insoluble in water - hence it stays on the rusted surface after reaction - and completely insoluble in organics.      It should provide a durable surface inside a fuel tank.

John

[Guest]

1 hour ago, JohnD said:

POR make a fuel tank sealing kit,

Thanks John, that is what I meant but you have quoted it correctly.

Link attached to eliminate any confusion: https://www.frost.co.uk/por15-car-bike-motorcyle-fuel-tank-repair-sealer-473ml/

Regards.

Richard.

[Badwolf]

I have actually seen a cut away motor cycle tank (admittedly it was in Frost's showroom, so it would be good) trested on the inside with POR tank sealer and on the outside with POR15. It had also been battered by the staff in front of customers to show how durable it was (a young lady on their staff took great delight in demonstrating with a large spanner). The results both inside and out were impressive but you MUST do it by the instructions and, as mentioned above, the surfaces to be treated must be bone dry or the paint will lift away in sheets.

[JohnD]

"the surfaces to be treated must be bone dry "

Wel, there's a plus for phosphoric - the acid is dissolved in WATER.   It's the ferric salt that isn't soluble.   Just dry out after.

[SpitFire6]

Hi,

I periodically add "dry Fuel" to my fuel to eliminate any standing water.

It works as I have zero rust last time I looked.

If I had a rusty tank internally I would fix with Phosphoric acid and ensure my fuel contained no free water by use of additives. Why would you coat the internal of a fuel tank?

Cheers,

Iain.