my craftsman garage door opener clicks like it wants to work but the door won't move

Diagnosis

This specific "clicking" sound on the Craftsman 57915 is the sound of the motor's internal starter capacitor and the drive gear attempting to engage, but failing to translate that rotational force into linear movement. Because this is a belt-drive model, the click indicates the motor is receiving power and the solenoid is firing, but the drive system is physically disconnected or obstructed. The root cause is almost always a failure of the drive gear or the drive sprocket. Over time, the plastic teeth on the main drive gear wear down or shear off completely. When this happens, the motor spins (the click is the initial torque), but because there are no teeth left to grip the belt pulley, the door remains stationary. You can confirm this by pulling the emergency release cord and manually sliding the door; if the door moves smoothly but the motor spins without moving the belt, your gear assembly is stripped. If the door is stuck and won't move manually, the problem is a mechanical bind in the door tracks, not the opener.

How to Fix It

To resolve this, you must replace the drive gear and sprocket assembly. You will need a Gear and Sprocket Kit compatible with the 1/2 HP belt drive series.

1. Disconnect the power by unplugging the unit from the ceiling outlet and turning off the circuit breaker to prevent accidental activation.
2. Pull the emergency release cord to decouple the carriage from the belt.
3. Remove the plastic light lens covers from the bottom of the motor unit by popping the tabs.
4. Unscrew the mounting bolts securing the motor chassis to the rail. Carefully slide the motor unit forward and off the rail, supporting the weight so it doesn't drop.
5. Open the motor housing by removing the screws on the side and bottom plates. Carefully lift the motor armature to expose the drive gear.
6. Remove the old, stripped gear. If the gear has disintegrated, use a vacuum or compressed air to remove all plastic shards from the motor housing; any remaining debris will jam the new gear.
7. Slide the new drive gear onto the motor shaft, ensuring the keyway is perfectly aligned. If your kit includes a new sleeve, slide that on first.
8. Reinstall the motor armature and tighten the housing screws.
9. Slide the motor unit back onto the rail, bolt it down, and reconnect the power.
10. Reset the travel limits using the "Up" and "Down" buttons on the side of the motor to ensure the door stops exactly where it should.

If That Didn't Work

• Check the Capacitor: If the motor hums but doesn't "click" and turn, the start capacitor (the large cylinder inside the housing) may have leaked or blown. Look for a bulging top or oily residue. Replace the capacitor with one matching the exact microfarad (µF) rating.
• Inspect the Belt Tension: Check for a snapped belt or a slipped pulley. If the belt has stretched too far, the motor will spin the pulley without gripping the belt. Tighten the tensioning bolt at the end of the rail until the belt is taut but not over-stretched.
• Verify the Limit Switches: If the opener thinks the door is already closed (or open), it will click and immediately stop. Check the limit switch wires for frays or breaks, and ensure the travel nuts on the rail haven't vibrated loose.
• Test the Logic Board: If the clicking is rapid and erratic, the logic board may have a failed relay. Try disconnecting the wall button and using only the remote; if the remote works, the wall switch or its wiring is shorted.

Heads Up

• Plastic Shard Warning: When a gear strips, it throws "plastic snow" throughout the motor. If you don't vacuum every single piece of debris out of the housing, the new gear will fail within weeks.
• Lubrication: Never use WD-40 on the belt or gears. Use a high-quality lithium grease on the gear teeth and a silicone-based lubricant for the rail.
• Spring Tension: Never attempt to loosen the bolts on the bottom bracket (the piece attached to the door) while the door is closed; the torsion springs are under extreme tension and can cause severe injury.
• Weight Check: Periodically check that your door is balanced. If you can't hold the door halfway open and have it stay there, the motor is working too hard, which is what causes the gears to strip in the first place.