Before doing any work on the garage door opener you must unplug the opener to guard against the possibility of an accident.
How to replace garage door opener gears.
This diy repair guide explains how to replace the gear and sprocket assembly on a chain drive garage door opener.
The worm gear attaches to the motor shaf.
This video from sears partsdirect shows how to replace the drive and worm gears on a chain drive garage door opener.
Step 1 unplug opener.
Located at the top of the motor unit the gear and sprocket assembly drives the chain that opens and closes the garage door.
If the gear and sprocket assembly breaks the motor runs but the door won t move.
Fortunately the repair is neither difficult nor expensive and it should only take an hour of your time.
If yours is a belt drive you need a kit like this https amzn to 2zqns.
This is a video on how to change the gear sprockets in a craftsman garage door opener.
Https amzn to 2uwvnkj i m working on a chain drive opener.
This was a craftsman model 139 53976srt.
This gear kit on amazon.