Re: Brew for cleaning filthy gas tanks

[amuller]

quote NJ-boatbuilder57:

I’ve read this thread a few times now, an I’m a little unsure: is this tank ‘dirty’ with old fuel that has varnished on? Or are we talking about rust?

(I have a rust issue & am looking for solutions…so I’m not sure if this thread’s suggestions are applicable for my tank)

I keep trying to make this point…

Most likely, you have old fuel varnish on top of rust, so you need to go after the varnish first. (Because if the tank was coated with "varnish" first it wouldn’t be rusty….) So I would start with solvent or strong detergent first, for the varnish, then go after the rust with some type of acidic cleaner. You might need nails or stones and agitation. Then, I would coat with POR because the plating will probably be gone from the steel.