fuel tank deposits

[red devil]

Recently, the fuel tank on my 65 year old model c has been depositing powdery rusty rubbish into the carburettor which is blocking the starter jet and restricting the fuel flow through the main jet. The carb has a filter above the float chamber but the particles are so small they seem to be able to get through the filter mesh.
Does anyone have first hand experience of a suitable tank sealant or some other method of preventing this problem.
The tank was last washed out when I restored the scooter 8 years ago, however it doesn't get used very frequently.

Thanks
Frank.

[jbcollier]

Remove and clean out your fuel tank. Lots of info on the web about this. Once clean, do not store with fuel in the system. Fuel these days breaks down quite quickly.

[red devil]

Thanks for the info. I had a look on the web were there is a bewildering array of products for sale!
I also had a word with a motorcycle restorer friend who recommended Flowliner sealant so I will be giving the tank that treatment.

Cheers
Frank.

[jbcollier]

If the tank is not leaking then you can use an acid/mechanical means of removing the deposits. First remove the tank and the fuel tap then fabricate or buy plugs for the filler and fuel tap holes (for example: rubber plugs from a hardware store). Now there are several options:

Acids

- muriatic acid, available at hardware stores. + works fast, readily available. - very strong and can be dangerous to handle, leaves bare metal which is will instantly start rusting if you don't coat it right away.

- phosphoric acid, in concrete cleaners (some), molasses, etc. + leaves a stabile surface that resists corrosion, only readily available highly diluted so safer to handle. - slow may take a week or more if you use molasses.

- acetic acid, vinegar use the pickling strength. + readily available, not so strong as to be dangerous. - slow (only know one person to go this way, he was happy with the results)

Mechanical

- if the corrosion is not severe, you can put a bunch of galvanized nuts in the tank, seal it with the plugs, wrap in towels and tape and then put in in your dryer. Half an hour to an hour later it will be as clean as a whistle.

[Tractorman]

POR 15 is very good, I've sealed several tanks with it without problems.