There is a part that probably broke. I have the same problem just today. The connection between the motor shaft and the wheel type thing with the vanes on top which I think the parts places call the counterweight is broken or stripped. Another blog list suggested cleaning the area, putting a light coating of oil all up and down the motor shaft, and then mixing up some standard JB Weld and putting that in the hole in the counterweight and sticking the motor shaft into the wet glue. Let it cure for several days, and see if it doesn't work again/
docjkl
December 2010