After soaking the inside of the tank in phosphoric acid all night, I was able to unscrew
the shut off valve pipe from the tank. There was a tiny remnant of a screen in the end
of the pipe. Got a lot of the rust and crud out with the acid and shaking screws around,
but got tired of that and sandblasted the inside and out. Though a very heavy wall tank,
I still ended up with three little pin holes from the rust, so I have sealer in it now.
According to a Doug Penn article, the “gold” color tank on mine was from a later model,
than the AA1 (1956) that the flywheel plate indicates. Mine is suppose to have a maroon
tank and say “Neptune” instead of “Mighty Mite”.
Prepare to be boarded!