I own an appliance repair company and had an unusual call. Had a customer that has an over the range hood whose motor runs much faster than normal. It is a "squirrel cage" type blower, 120 volt. It has 3 speeds and is borderline violent at high speed. He bought it open box on sale, and has been like this since its initial install this week. I didn't do the install, he called when the motor had problems. Interestingly, if the capacitor is disconnected after start up, the run speed drops to normal. Could this be the issue? I'm almost positive that it is a start capacitor. Also when i test the voltage at the motor harness terminations, the motor is running at almost 180 volts, yet the line in voltage remains at 120 volts. Im pretty good with appliances, but this is puzzling me. Any and all help is appreciated. Thanks in advance.