Report "2 hp, mod # 139.53603. When I press the remote or the panel button there is a humming sound from the motor. I opened the panel on the back and did not see anything out of line, etc. When pressing the button, it seems like the shaft coming up from the worm drive motor shaft to the outer gear tries to move back and forth but cant (seems to be binding). I can turn the worm drive shaft from the motor by turning the black cap on the outside. The chain does not seem to be binding but the shaft definately wont move. Thanks"