I have a Craftsman model 139.53671SRT garage door opener. The motor hums, but the chain won't move. The trolley is not stuck on the stop bolt. Any other ideas?

Jimmy K EXPERT March 16, 2009

Look at the led on the motor unit of the garage door opener. It is probably flashing a code. I am sending you an image that explains the flash codes of the led.

Does the garage door close or open from the wall control? Does the motor hum when you press a remote button or the wall control button?

If the door is closed, pull the emergency release rope on the trolley and raise and lower the door by hand several times. If the door opens and closes easily and will stay half open if you turn it loose, we know the problem is in the garage door opener.

If the door is open and a door spring is broken, when you pull the emergency release rope the door will close very hard and might damage anything that is in the way.

Test these things and send another email. Give us the details and we will try to help you repair the problem.

rodneydyck March 17, 2009

My operator would not open or close the door and would hum when the button was pressed. The main plastic gear was stripped. Take off the small screws holding the cover on and look for white plastic "snow", that is the remains of the gear. You can get new assemblies from sears or amazon and install it yourself or get a repairman to do it.