How to Get the Gear Off the Assembly for a Craftsman Garage Door Opener

Push the wall button to close the garage door, if it is in the open position. Stand a stepladder under the opener's motor head. Unplug the power cord from the outlet in the ceiling.

Move the stepladder under the door opener carriage where the door arm connects to the opener. Find the two nuts that secure the threaded chain bolt to the carriage. The nuts are on each side of a flange on the carriage.

Loosen the nut on the side closest to the door with a wrench. The chain will develop slack as you loosen the nut. Continue loosening the nut until the chain droops below the opener rail. Do not remove the nut completely from the threaded bolt.

Position the stepladder back under the rear of the door opener motor head. Pry the plastic cap that covers the gear on the top of the opener with a flat-head screwdriver. Grab the chain around the gear sprocket and pull it off the gear.

Hang the gear end of the chain on the stop bolt on the rail just in front of the opener head. This helps prevent you from dropping the chain completely and twisting the chain.

Remove the set screw on the neck of the gear with a hex wrench. The set screw is on the neck between the gear and the top of the opener.

Position the claw of a hammer under one side of the gear and pry the gear slightly. Move the claw to the opposite side of the gear and pry again. Continue prying one side and the other until the gear comes off the shaft.