Take it out, and search the part number on line, they are bout $40 with s/h. however my current discovery:
It made no sense to me that despite no visual issues, the fan motor is bad. So, with further research it turns out that the true culprit is the small thermistor/thermal fuse between the orange wire (ground) and motor winding wire. The thermistor is taped underneath the silver aluminium and yellow tape on the fan motor. I heard about this bad (open/no continuity) thermistor makes almost >99% of the fan motor problem regardless of any brand name because this cheap c-fram fan motor is NOT made in USA. I opened the motor, there is a silver (aluminum wrap) around the windings for the motor that needs to be cut. Careful not to cut the motor windings. Inside there is a thermistor or type of temperature sensor connected between the orange wire and a motor winding wire. On my motor this was no longer working.
The part marked "JET 123 NM1 2A 130C" is a thermal fuse. The 130C is the temperature rating. When the motor get hot (130C / 265F) the fuse opens. The circuit is broken and the motor stops.

The motor is still good. The fuse is blown. It must be replaced to get the motor running again. You could bypass the fuse but then you invite a fire hazard.

A replacement fuse is available from Digi-Key. It is a Cantherm SDJ1 DF128S (128C):
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=317-1133-ND
Part cost 98 cents

You might want to go with the next higher temp (141C):
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=317-1134-ND