Garage Door Sprocket Broke Off

Pull down the trolley cord to release the trolley from the chain arm and lower the door by hand.

Garage door sprocket broke off. You can remove the three mounting screws from the sprocket bracket using a 5 16 nut driver for the 2 easily accessible screws and use a 1 4 drive ratchet and 5 16 socket for the one that s harder to reach. I do all of this with the door closed and the trolley slid all the way out in the door closed position and locked to the door. Use a step ladder to access the garage door opener s power cord and motor unit. This turns the chain and moves the door.

Position a work table near the area under your motor unit to hold the garage door opener. This gives the appearance of a broken chain or belt. How to fix a garage door chain drive sprocket 1. This was a craftsman model 139 53976srt.

Eventually this will cause the sprocket to snap off. Your garage door opener has a gear and sprocket that will eventually fail. The most common issue that occurs is when the ridges in the gear wear out because the gear lubrication has evaporated. One of the most common repairs on a liftmaster garage door opener is a broken gear sprocket.

Loosen the bolts on the chain pulley that s. Liftmaster and chamberlain garage door openers are very common for this. Lower the motor unit down. In most chamberlain liftmaster and sears openers a motor turns the worm gear and drive shaft inside the opener which rotates the sprocket attached to the top of the drive shaft.

Move the ladder to the outer end of the chain arm near the garage door. Remove the chain and cable assembly. Over time though this slack can increase or the gear and sprocket assembly can wear and the chain may pop off the sprockets. You can put the chain back on your automatic garage door opener using a simple adjustment mechanism.

This is a video on how to change the gear sprockets in a craftsman garage door opener. The cost of the new gear and sprocket replacement is around 160 220 depending on the state and area you live in and it s include labor to install the new part. This can be easily replaced by a garage door service technician.