The chain wraps around this sprocket as well as the gear and sprocket at the motor.
Garage door opener sprocket broke off.
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.
Chain driven garage door openers should have some slack in the chain for optimal performance.
Over time the sprocket s teeth can wear and the chain may jump or skip when the opener raises the door.
Eventually this will cause the sprocket to snap off.
Located at the top of the motor unit the gear and sprocket assembly drives the chain that opens and closes the garage door.
A new front sprocket costs about 150 200 include the labor to install it.
Sprocket is at the end of the opener rail closest to the garage door opening.
This was a craftsman model 139 53976srt.
This gives the appearance of a broken chain or belt.
You can put the chain back on your automatic garage door opener using a simple adjustment mechanism.
If you are not confident in your ability to diagnose the problem call a local garage door service company.
After several years the garage door springs become weaker causing more stress on.
This diy repair guide explains how to replace the gear and sprocket assembly on a chain drive garage door opener.
This is a video on how to change the gear sprockets in a craftsman garage door opener.