Gempler's rust converter has a 9 month shelf life according to the bottle, and I have some that is 2 - 3 years old. It has been sealed up and not froze. It seems to be working fine, but the finish when dry is a little more dull black than shiny like I usually see. Could there be any problems with it? I'm painting over it. Wondering if the paint would not stay on as good?
Gempler's Rust Converter question
