what is the current draw when you try to run engine, if over 1 amp definitely something wrong with motor you have ! also disconnect yellow white wire that feeds motors from ps 3 board so you don't damage when you do this check. then test motor continuity and report back what that is. then try to run motor with dc power supply and see if it in runs normal also put current meter in series with meter to see how how your amp draw is. I'll almost bet you have a bad motor, I would test both motors disconnected from the board this way as stated above ! also you gave us the wrong engine item number !
the closest engine number I can find is 30-20393-1 .
Alan
