How to Remove Spools on Homelite UT21947 Mighty Lite Trimmers
- 1). Turn off the Homelite UT21947 Mighty Lite string trimmer and allow the trimmer head to completely stop. Pull the spark plug wire boot off the top of the spark plug with your fingers. Place the trimmer on its right side with the fuel tank filler neck pointing up and the bottom of the trimmer head pointing to the side.
- 2). Hold the side of the trimmer spool housing with one hand. Turn the bump knob counterclockwise with your free hand. The bump knob is the plastic knob on the bottom center of the trimmer head. If necessary, turn the bump knob with a pair of slip-joint pliers.
- 3). Pull the spring away from the bottom of the spool if it does not come off with the bump knob. Keep the spring in a safe place with the bump knob for re-installation once you restring the spool, or purchase a pre-wound spool.
- 4). Remove the bump knob from the bottom of the trimmer head. Continue holding the housing in one hand and pull the spool out of the housing with your free hand.
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