Pull down the trolley cord to release the trolley from the chain arm and lower the door by hand.
Garage door chain sprocket tie down.
When the sprocket rotates clockwise and stops by itself the motor will be in a closed position.
Slide the outer trolley away from the inner trolley.
Grasp the chain 1 foot from where it connects to the end of the threaded chain anchor.
Stand on a ladder so you can look down towards the top of the sprocket.
I tried to work with the down screw to put it in reverse but that did not help.
Lay the chain on the garage floor while you complete the repair.
When used on tube shafts it is advisable to fill the tube shaft with a steel or wood dowel in the area of the sprocket and through bolt the sprocket.
34 1 02 oz 20 62 20 62.
Liftmaster 41c4220a gear and sprocket kit for chamberlain sears craftsman and liftmaster 1 3 and 1 2 hp chain drive models 4 8 out of 5 stars 3 339 20 34 20.
Pull the chain toward the garage door and hold it in position.
Press down on the chain with your finger.
Remove the outer nut and lock washer from the trolley threaded shaft and pull the threaded shaft out of the trolley.
Plug the opener back in.
I had a chain come off the sprocket on my chamberlain garage door opener.
Drill through the sprocket and shaft and install a bolt hardened bolt if needed through the shaft.
I loosened the nuts to allow me to put it back on tightened it back up and now the door goes down but comes 1 3 of the way up again.
Activate the opener via remote control and watch the sprocket.
Loosen the chain or belt tension and slip the chain or belt off the sprocket.
Can be used on tube shafts.
Place a stepladder near the motor and unplug the power cord for the motor from the electrical.