If you were using catalyzed primer (epoxy primer) and allowed it to dry (cure) in your gun, I'm sorry to tell you that was a mistake you might not be able to correct. With some of these epoxy primers and paints, acetone will help dissolve them after they've been cured (hardened), but it isn't a promise. And your spray gun may never be the same again. We used to use MEK (methyl ethyl ketone), but if you can even find any MEK...use that stuff ONLY in well-ventilated areas, don't get it on you or your clothes and don't inhale it any more than you must. Lacquer thinner won't do much even over a very long time. Good luck.


~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end