Sorry, the web browser you're using is not supported by this website.

Please use Google Chrome, Firefox, Safari, or another browser to access Thank you.

Skip to main content

We use cookies to enhance your experience. For details on how we use cookies, collect data, & how to manage your consent please see our Cookie Policy & Privacy Policy.

How do I replace a Drive in a Garage Door Opener?

The worm gear is attached to the motor shaft and rotates the drive gear to move the door. If the door suddenly hits an object in its travel path, the worm and drive gears strip out to protect the motor from damage. If the drive and worm gears are stripped, replace them.

Follow these steps to fix your issue:

  1. Disconnect power

    The power cord and motor unit of the garage door opener can be accessed using a step ladder.

  2. Take the garage door opener down

    To hold the garage door opener during the repair, place a work table under the motor unit. The trolley needs to be released from the garage door. If the garage door isn't already closed, shut it. The straight door arm has a ring on it. The garage door can be disconnected from the outer trolley by pulling out the clevis pin. Place the straight and curved arms against the garage door. If necessary, use a helpers. The wall control and safety sensor wires are connected to the motor unit. The wall control and safety sensor wires are connected to the motor unit. You will refer to the photo when you connect the wires. The wall control and safety sensor wires need to be disconnected. The light cover needs to be closed. The motor unit is secured with nuts, bolts, and lock washers. Attach the motor unit to the ceiling with one hand. Carefully lower the motor unit and secure it on the step ladder. Take the motor unit down the step ladder and put it on the table. You should move your ladder by the garage door to get to the rail. The clevis pin has a ring on it. Pull the clevis pin out of the rail with one hand. If you want the rail to be level with the motor unit on your table, lower it and rest it on a rung of the step ladder. If you want to avoid scratching a decorative garage door, remove the nuts, bolts and washers from the curved arm and rest it against the door when you disengage the garage door from the outer trolley. When taking the garage door opener down, you may want to have a helpers help you.

  3. Remove the chain and cable assembly

    When you replace the drive and worm gears, mark a link of chain and the sprocket tooth that meshes with it with a felt-tip marker. The outer trolley should be moved away from the inner trolley. Pull the threaded shaft out of the trolley and remove the outer nut and lock washer. Pull the chain out of the spreader. While you complete the repair, lay the chain on the garage floor.

  4. Remove the gear and sprocket assembly

    Light covers and light bulbs need to be removed from the motor unit. Pull the chain spreader off the motor unit by removing the screws. Pull the motor unit cover off if you want to remove the screws from the motor unit cover. Pull the helical gear off after removing the plastic retainer. To release the limit switch locking tabs, squeeze the sides just below the motor brackets. The limit switch should be moved aside and hung by the wires. The gears and sprockets need to be removed from the mounting screws. Take the gear and sprocket assembly out.

  5. Remove the motor

    Plug the RPM sensor wire harness if you want to remove the main bearing from the motor plate. The motor shaft has an interrupter cup. The front of the motor plate has mounting nuts. Pull the motor out of the plate and place it next to the motor unit. Pull the motor shaft bearing out of the motor plate after Prying off the motor shaft bearing retaining clip. On some models, you'll need to loosen the set screws on the set collar and remove the set collar from the motor shaft, then remove the washer cap, spring washer, flat washer and bushing from the motor shaft before removing the mounting nuts from the motor plate.

  6. Replace the worm gear

    To remove the front roll pin from the motor shaft, use a punch and hammer. The worm gear should be pulled off the motor shaft. The O-ring, C-ring and spacer are in the motor shaft. There are new O-ring, C-ring and spacer on the motor shaft. After lubricating the worm gear, slide the new worm gear onto the motor shaft and engage the rear worm gear on the roll pin. The front roll pin needs to be reinstalled. Pull the worm gear off the shaft if the motor has a roll pin behind it.

  7. Reinstall the motor

    Attach the new motor shaft bearing to the motor plate with a sockets and push the mounting clip against the motor plate. Remove the motor mounting nuts after pushing the motor into the plate. The motor shaft has an interrupter cup on it. Put the new main bearing in the motor plate by lubricating it with grease. Remove the wire harness from the RPM sensor. If the motor has a set collar, you should push the new bushing onto the motor shaft and slide it against the motor plate to engage the notch on the bushing in the slot on the motor plate. The motor shaft has a flat washer, spring washer, and washer cap. The washer cap should be moved against the motor shaft. To eliminate shaft play, push the motor shaft through the set collar from the back of the motor, and tighten the set screws.

  8. Replace the drive gear

    To drive the roll pin out of the drive shaft, use a punch and hammer. The drive shaft has drive gear on it. Put the new drive gear onto the drive shaft and line up the mounting hole with the hole in the drive shaft. The roll pin needs to be inserted into the gear and drive shaft. The roll pin can be driven using the punch and hammer. grease the new drive gear

  9. Reinstall the gear and sprocket assembly

    Attach the mounting screws to the gear and sprocket assembly. Grease can be applied to the gear. Push the gear onto the shaft and secure it with a retaining clip.

  10. Reinstall the limit switch and motor unit cover

    If you want to engage the limit switch drive gear with the helical gear, you have to position the limit switch on the motor brackets. Attach the motor unit cover with the mounting screws. Light bulbs and light bulb covers need to be reinstalled. Attach the chain spreader with the mounting screws.

  11. Reinstall the chain

    Making sure not to twist the chain, thread it through the chain spreader and around the motor unit sprocket. Remove the inner lock washer from the threaded shaft by threading the inner nut up to the top. Remove the outer nut and lock washer from the trolley and place it in the hole. It is easier to thread the outer nut onto the trolley shaft if the inner trolley is pushed toward the threaded trolley shaft.

  12. Tighten the chain

    The trolley threaded shaft needs to be adjusted so that the chain hangs above the base of the rail. To get the trolley threaded shaft, tighten the inner nut against the trolley.

  13. Reinstall the garage door opener

    The rail end should be connected to the brackets using a clevis pin and ring. Set the motor unit on top of the step ladder when you position the ladder under the ceiling. Use nuts, bolts and lock washers to put the motor unit back in the ceiling. The wall control and safety sensor wires need to be reconnected to the motor unit after you open the light cover. The light cover must be closed. Attach the straight door arm to the outer trolley by using the clevis pin and ring. The trolley must be re-engaged. If you disconnected the curved door arm from the straight door arm while freeing the garage door from the outer trolley, you should use the bolts, lock washers and nut.

  14. Reconnect electrical power

    The garage door opener should be plugged in.

  15. Adjust the travel limits

    To check upper and lower travel limit, run the garage door opener. If the garage door does not completely close, adjust the down travel and cycle the door open and closed to see if the adjustment is right. Continue adjusting the travel until the door closes completely. If the door doesn't open completely, adjust up travel the same way. The motor of the garage door opener can become overheated and shut off if it is continually operated. Allow the motor to cool and then adjust it.

Time required:

60 minutes.

You would need the following tools:

allen wrench set, emery paper, hammer, punch set, slot screwdriver, socket wrench set, step ladder, work gloves, work table.

Let's Get It Fixed!

HomeX virtual experts will assess your issue (for free!) and can resolve simple problems.

What Did You Think of This Article?

What Did You Think of This Article?