what is causing the sounds your garage door makes

How To Replace Garage Door Opener Gears

If you get a low hum from your garage door opener, and the door doesn't open, the gear has likely malfunctions. Gears malfunction for many reasons, such as age, shredded gears, or excessive use. Garage door opener gears aren't difficult for a novice to replace. Follow these tips to replace garage door opener gears.  

Prepare to Work

For this project, you need:

  • work gloves
  • step-ladder
  • slot screwdriver
  • hammer
  • Allen wrench
  • socket wrench set
  • punch set
  • WD-40 

Disconnect the power cord, which is commonly located on the ceiling, to the garage door opener, so the door can't be opened from outside. Pull the emergency release cord, and close the door all the way. To further secure the door, attach a vise grip or clamp above a roller.

Remove the Old Gear Assembly 

Set the step-ladder, so you can easily reach the opener gear. Use the screwdriver to detach the screws on the opener light cover. Remove the cover and the light, then set the parts and hardware aside. If you need extra room to work, loosen the screws on the circuit board, and let it dangle.

You should now see the screws that hold the motor housing end covers in place. Loosen the nut on the chain attached to the tension rod with a wrench. Use another pair of pliers to hold the chain while loosening the nut, if needed. 

Snap a photo of the wiring, and disconnect the three wires. These wires are commonly red, blue or black, and white. The red, black and blue wires are positive and the white wire is commonly negative.

Remove the three or four screws on the motor housing with a socket or nut driver. Keep one hand on the case while you remove it, and lay the case and hardware aside.

Detach the helical (round) gear from the shaft by holding a punch over the pin, and tapping it with a hammer. The punch should have a s lightly smaller diameter than the pin. If you have trouble removing the pin, lubricate it with WD-40. Let the lubricant soak and try again.

Install the New Gear Assembly

Connect the new worm gear to the shaft, and reconnect the motor housing and wiring following the photo you took. Rub a thin layer of WD-40 on the helical gear. Reverse order to install the new gear assembly, and reassemble the motor housing. Reinstall the circuit board cover, if needed. 

Restore power and test the repair. If the door still doesn't work properly, or you don't trust your skill, contact a garage door service such as AAA Garage Door, Inc.