Mo,I have a 139QMB motor that will not charge. I have changed the rectifier with one from my other scooter and it still will not charge. How do I test the stator? Steve
To test the stator you will need a multimeter with an ohms (resistance) function and an AC Volts function. First locate the stator wiring coming out of the motor on the right hand side. Disconnect the 3 wire plug. Now with your multimeter in Ohms X 1, on the stator side of the wiring, take one lead and probe the green wire and the other lead and probe the white wire, you should read around 1 ohm. Now probe the yellow wire with one lead and the green wire with the other, again you should read around 1 ohm. If either reading is zero or no reading (infinite ohms) the stator is bad. Another way to check a stator is with a voltage reading with the scooter running. Be careful not to get your leads around any moving parts, such as an open stator fan or the rear wheel. It may help to have someone help you with this test. Place the multimeter to AC Volts and place your leads across the green wire and the white wire just like in the resistance test. Start the scooter and momentarily rev the motor above 4000 rpm, you should read above 30VAC, do the same with the yellow and green wires.