My garage door won't open or close. What causes this?

Jimmy K EXPERT February 05, 2009

Disconnect the power to the opener and remove the outer cover. Inspect the nylon gears for wear. Restore the power and start the opener. If the gears are turning but not moving the trolley the gears need to be replaced.

I am sending you instructions for replacing the gears in case they are stripped. You can look at the job and decide if you want to do the repair yourself.

Unplug the garage door opener from the power. Loosen the chain at the trolley and remove it from the sprocket on the opener.

Remove the outer cover from the motor unit of the opener.

Remove the 3 screws that hold the sprocket and gear assembly to the top of the motor unit and lift the assembly out the top.

Remove the clip and the gear that drives the limit switch. Note the position of the door and of the limit switch. be sure they are in the same approximate positions when you reassemble.

Remove the screws that hold the motor to the motor unit housing and remove the motor unit. Mark the wires as you remove them so you can put them back as they were.

Drive the roll pin out of the motor shaft and slide the worm gear off the shaft.