Review on Liftmaster 41C4220A Chamberlain Craftsman LiftMaster by Dave Russell

The best repair experience I've ever had ordering parts online. The gear on my 2003 Craftsman 1/2 hp opener was worn out and the drive shaft broke off. Using the included instructions and a YouTube video, I was able to fix the opener and have it up and running in less than an hour. You can leave the opening rail attached above the door and simply release the end of the motor to lower to a comfortable working height. A NOTICE. With the drive open, pay attention to where your limit switches are. When the garage door opener opens or closes the door, there is an adjustable contact that tells the door to stop in the correct open position and one for the closed position. If you look at the attached picture, the middle screw is the door. The limit switch and the top and bottom screws are where YOU set the door stop points by twisting the ends with a screwdriver. When the opener is closed and running you cannot see where the pins are. You can only see how big the difference in the screw setting is when the door stops or not. As the door moves, the threaded center rod rotates and the contact moves until it touches one of the contacts, stopping the motor. Once you have replaced the main shaft and sprocket and put the chain back on the sprocket, it is very useful to know if the door limit switches are in the closed or open position so you can check if the door is in a position in near where the limit switches are located. Then it's just a matter of fine-tuning the gate travel by a couple of inches, not a blind start. Also note that opening the garage door again to fine-tune can overheat the motor, causing it to shut down to cool. Don't let that confuse you.