| Problem | Likely Cause | Solution | | :--- | :--- | :--- | | | Loose spindle taper or bent chuck | Re-seat chuck with rubber mallet. Replace JT3 chuck. | | Motor hums, won't start | Capacitor failure (S68 uses 125 mfd) | Replace start capacitor (Part #S68-E4). | | Drill wanders | Loose belt or worn step pulley | Tension belt. Replace pulley if grooves are glazed. | | Quill drops suddenly | Broken return spring | Remove pinion shaft. Wind spring 3 turns (see Fig. 7). |