citric degreaser

[news]

Can anyone recommend a cheap citric based degreaser? I need to clean old petrol varnish off a long unused motorbike tank as it is currently flaking off and blocking the fuel c*ck.

AJH

[newshound]

Not sure I would be confident that modern limonene degreasers (such as Citricent) will actually attack the lacquer/varnish that can be formed by oxidised hydrocarbons. That said, I associate such lacquer/varnish polymers more with lubricating oils than fuel.

Assuming your problem is correctly diagnosed, I think I would start with mechanical attack, for example some sort of sand blasting. You might follow this up with something like angular granite chippings, either shaken manually or perhaps putting the tank on a mechanical shaker at all necessary orientations.

Also, your fuel c*ck should have a wire mesh filter protecting the intake. You must have a *lot* of material coming off if this is causing problems. Which makes me think that a sufficiently aggressive mechanical attack would soon separate almost all of it.

Is it *really* varnish, or mostly rust? If rust, then any strong acid should sort it (hydrochloric, sulphuric, nitric). You might consider phosphoric.

[stvlcnc43]

Does phosphoric acid remove rust, or does it convert rust to iron phosphate?

[newshound]