Muriatic acid (hydrochloric acid) is a solution of the gas HCl (hydrogen chloride) in water. The HCl can indeed "evaporate" and get at stuff other than your parts. I've used Ospho which is phosphoric acid dissolved in water.
Sorry for the chemist in me rising to the top.
1948 3/4-Ton 5-Window Flatbed Chevrolet 34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
