Which part number do I need to change out the drive/worm gear assembly on my garage door opener?

HVAC & Fireplace Bucket EXPERT April 21, 2008

The part you are looking for is the 41A2817 part number. That is a complete kit with everything you should need. The 41C4220A number is a few individual parts and is intended for situations where everything is relatively new and in good shape but one specific part has failed.

Instructions will be included with the kit that should help with the install. Looking at the exploded views in your manual or at the Sears Parts site will also give you some idea of how the parts fit together and what will need to be disassembled in order to get the job done on your particular model.

If you start with the door trolley all the way up and the limit switch in the up position and then install your parts you will have a good reference point to get the two back in sync afterward but remember that you still may need to fine tune the upper and lower limits slightly when you are finished.

Also, take care to get the wiring hooked up correctly for the RPM sensor; it is possible to put the plug on the prongs off-center so that one of the prongs is not actually in the plug. And push the Interrupter Cap all the way onto the motor shaft so that the notches in it will alternately open and close the view to the sensor as it turns.

Once you are finished you will also need to test your safety systems to be sure the door is stopping and reversing as it should for safe operation. And there is additional important information in your owner’s manual that you might want to review.

This is a fairly major repair, so if you have any remaining concerns or doubts feel free to submit further questions here at Manage My Home or you may want consult a professional to be sure there is no risk of the door jamming or hurting someone after the job is completed.