2025-06-05

Troubleshooting a Stuck Lead Screw

Overview
The Powerwall dolly has spring washers to help prevent the lead screw from getting stuck at either end of travel. However, the lead screw can bind if it hits the end of travel while turning at high speed or high torque. To avoid hitting either end of travel, always look at the stickers on the plastic shields (shown below) to know when the lead screw is approaching the end of travel, and stop the lead screw before it hits the end of travel.

If the lead screw does bind at the end of travel, follow the steps in this procedure to unbind it.

Tools and Equipment

  • 3/4” or 19 mm Wrench
  • Large vise grips
  • Torque wrench
  • 5 mm Hex bit for the torque wrench
  • Rubber or thick rag

  1. Lay down the dolly and inspect the base of the lead screw.
    1. If the threaded shaft collar has not moved and there is no gap between the threaded shaft collar and the base washers, continue to step 2.
    2. If the threaded shaft collar has moved up the lead screw and there is a gap between the collar and the washers, skip to step 3.

    a - No gap between the collar and washer - go to step 2

    b - Gap between the collar and washer - go to step 3

  2. If the threaded shaft collar is still at the base bracket, it is likely that the spring washers are fully compressed and the drill cannot overcome the friction.

    To unbind the lead screw, use the 3/4” (or 19 mm) wrench to turn the hex drive clockwise (when viewing the screw from above). Test to make sure that the screw rotates freely. If it does, the procedure is complete. If not, proceed to step 3.

  3. If the threaded shaft collar has moved up the lead screw, it needs to be moved back toward the bottom of the screw.

    The clamping screw is likely already loose, but if it is not, use the 5 mm hex bit or an Allen key to loosen it.

    Loosen this screw

  4. Use some rubber or a thick rag to wrap around the threaded shaft collar and protect the finish. Use the vise grips to hold the body of the collar, ensuring to only grab the collar.
  5. Turn the threaded shaft collar counterclockwise (when viewed from the bottom of the dolly).
  6. Once the threaded shaft collar is loose, thread it to the base of the lead screw. Make sure that the three plates under the collar are stacked back-to-back and not resting on the screw heads.

    Rotate the collar until the base rests on the washer

  7. Use the 5 mm hex bit in the torque wrench to secure the clamping screw on the threaded shaft collar to 16 Nm.

    Tighten the shown screw to 16 Nm

  8. Test the system to ensure that the lead screw rotates freely.