Motor Capacitor Review

Once the back cover and the lever have been removed, I could see lots of dust and dirt around the motor. I used a vacuum cleaner together with a brush to clean up the dust. You could also see a motor starting capacitor attached beside the motor. This is the Metallized Polypropylene Film type of capacitor. The function of the motor start capacitor (AC motor capacitor) is to provide that electrical "push" to get the motor rotation started. Without a motor starting capacitor (such as when one open circuit or burns up), when the voltage is applied, the motor will just sit and hum. But if you were to grab the shaft (or the propeller) and give it a spin, the motor would (usually) start and run normally. I do not think the capacitor have problem because the symptom was the shaft jammed causing it not to rotate.

Anyway I took out the capacitor and check it with a digital capacitance meter to see if the capacitance is within range or not. The value was, and it is slightly lower then the tolerance (the tolerance for this type of capacitor is about 10%). If the capacitance value is too low then I will replace it with a new one. Please make sure you get a replacement with the same or higher voltage and if possible with the same capacitance. You can easily get a motor starting capacitor from any electronic distributors. I put back the capacitor and start servicing the fan.