Garage Door Chain Sprocket Broke

Chain drive garage door openers have a sprocket that is attached at the top of the motor.

Garage door chain sprocket broke.

One of the most common repairs on a liftmaster garage door opener is a broken gear sprocket. Liftmaster and chamberlain garage door openers are very common for this. Chain driven garage door openers should have some slack in the chain for optimal performance. This was a craftsman model 139 53976srt.

Your garage door opener has a gear and sprocket that will eventually fail. This is the part that connects the motor to the chain or belt. Over time though this slack can increase or the gear and sprocket assembly can wear and the chain may pop off the sprockets. This is a video on how to change the gear sprockets in a craftsman garage door opener.

Located at the top of the motor unit the gear and sprocket assembly drives the chain that opens and closes the garage door. This can be easily replaced by a garage door service technician. The gear and sprocket assembly is inside the cover of the garage door opener motor. You can put the chain back on your automatic garage door opener using a simple adjustment mechanism.

After several years the garage door springs become weaker causing more stress on this particular part causing it to fail and wear out. I am not a professional. If the gear and sprocket assembly breaks the motor runs but the door won t move. Documenting how i repaired the garage door.

The most common cause of a chain being loose and appearing broken is a broken gear and sprocket.