help!!!!!!!!!!!!

[joe62]

My gdo is sears 1/2 hp model no. 139.53627srt. Door is up and when activated; motor hums for a couple of seconds and stops. thanks for any help.

[HayZee518]

there is no belt in the gdo. pull the carriage rope and see if the door can move along its track. manually close the door and hit the activate button. if the motor just hums and nothing moves then I would suspect the nylon drive gear is stripped. the drive gear uses a woodruff key with a set screw.

[jeffkellen]

I agree, it is most likely a stripped drive gear inside the motor- very common with these openers. If you remove the cover on the motor (simply remove the 4-8 screws that hold the housing on). If you see a bunch of white plastic "shavings" that fall out, you have a stripped gear. You can clearly see the gear at this point to confirm. You can order a new gear pretty cheaply and there are plenty of YouTube videos that show you how to change it out. It's Prettty simple. Hope this helps!

[gdoorpro]

I doubt that it is the drive gear, sounds to me like it might be jammed up against a limit or it might need a capacitor, or a rpm sensor. check the diagnostic light near the learn button. It will blink x number of times to give you a good idea of what the problem is.