Just saw my copy of "Free For All" for the 4th time! Comedy from 1949 with Bob Cummings;- he tries to get pill patented for water to fuel gas formula. (based on real similar incident at that time) See worried Oil co executives give chase. Runs engines on water. Good lines, good laughs. You should buy this VHS tape from Ralph's Music , 1010 Hillcroft Rd, Glendale, Ca. 91207, or kamenrider on Ebay. His tapes are the clearest than other vendors that sell same title.
The above movie is much better than the other one - The Water Engine.