Here is an excerpt on electric lawn mower motors that I found in the February 1967 issue of Popular Science: ELECTRICS HAVE THE POWER (written by Jackson Hand) "If you're one of those who tend to think electric mowers are kind of puny, think again. Typically, a good electric has a universal motor rated at about one to 1.5 hp. Universal motors run at about 15,000 RPM or so, as is done in the Lawn Boy, the Thor, and the single-blade Sunbeams, and you get three things: a) Power. The high-load torque of such mowers equals that of at least three-hp gasoline burning engines.; b) Minimized slowdown under load; and c) Quick stop of the blade when you turn the switch off - an important safety feature. Twin-blade mowers such as Black & Decker and two Sunbeam models have belts instead of gears to reduce motor speed and provide equivalent power. Black & Decker models have flat belts, fiberglass reinforced, that operate without overheating at high speeds. Sunbeam uses toothed timer belts, necessary because the side-by-side blades must be synchronized so they don't hit each other. (The Black & Decker blades are staggered.) Since blade-tip speed is an important factor in safety, held to 21,000 (now 19,000) feet per minute by the industry's safety code, these gear-downs serve the double function of bringing lightweight electric motors into efficient power range and of reducing blade speed to a point where hard objects thrown by the blade are less likely to be lethal." ~Ben

thanks to all for responding. If you'll pardon the pun, I think a light just turned on! the diagram on the switch carton showed the motor 'load' (thank you) attaching to the two 'top' connectors. (top, as in the top of the switch). I think you've shown me my error. Apparently, I need to attach the power lead to the top brassy terminal and the motor lead to one of the bottom black terminals. my switch has four terminals and a ground terminal. I'll let you know how it works out. I do appreciate the feedback. P.S. what I meant by 'stops working': I go on vacation. Turn off the switch so the gate doesn't accidentally get opened while I'm away. (it happens with remote controlled devices) Thus, the importance of a switch, right? So, I turn off the switch--which cuts power to the unit. When I return home I turn the switch ON and that's when my problem started: I got no power after I turned on the switch. It's as if I'd burned out a fuse/breaker--which I didn't since I could directly connect my power leads to each other instead of the switch and the gate opened/closed just fine. And, finally, I'm fairly certain that the switch is the correct type because the carton specifically states it is for use in applications involving motors. It is rated at 20A/120-277V. The switch used previously was a common house-hold switch installed by the previous home-owner.

<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /> Do some investigating toward a minor repair “if possible”. Search for a manual or youtube that might show the needed sheared key or etc.. The diagram at the address below might be related. Good Luck! http://c.searspartsdirect.com/lis_png/PLDM/P0804140-00001.png PS. There is an added address insert that I c/n remove.

I take it you got this motor used? I think you've probably analyzed the situation pretty well. It does appear that the starting winding failed (it reads open when measured for resistance), and that some previous owner tried hacking the motor, hoping to make it work without the starting winding. The fact that it hums and then will run in either direction if you hand start it sounds about right. I'm far from a motor expert, but I think that capacitor start motors also use a starting winding. Without a working one in your motor, I think you're probably stuck. But I will defer to anyone else with better motor chops.