Replaced gear and worm on craftsman 139 53970srt.
Replacing worm gear craftsman garage door opener.
Step by step garage door opener gear fix.
Use a punch and hammer to drive the roll pin out of the drive shaft.
Flip the motor unit over.
So if you suddenly find that the motor on your garage door opener sounds like it s running but the door is not moving checking for worn gears is the first thing you should do.
Slide the new drive gear onto the drive shaft and line up the mounting hole in the drive gear with the hole in the drive shaft.
Remove the light covers and light bulbs from the motor unit.
Remove the screws from the motor unit cover and pull the motor unit cover off.
Replace the drive gear.
I did the repairs with the door fully closed.
Pull the drive gear off the drive shaft.
This was a craftsman model 139 53976srt.
Fortunately the repair is neither difficult nor expensive and it should only take an hour of your time.
Remove the screws from the chain spreader and pull the chain spreader off the motor unit.
Shredded plastic gears are a common problem with chain driven garage door openers.
This is a video on how to change the gear sprockets in a craftsman garage door opener.
Tried to adjust up and down limits with not success.