- 1). Push the ignition switch to the "Off" position. Allow the engine and muffler to cool for several minutes to reduce the risk of fire and burns.
- 2). Set the trimmer on a flat workbench to work comfortably on the trimmer head. Hold the moveable part of the head in place with your hand. With the other hand, twist the cap counterclockwise to remove it.
- 3). Pull the spool out from the trimmer head. Clean the spool with the rag and inspect it for damage, such as cracks, dents or holes in the plastic. Refill the trimmer string if needed.
- 4). Push the spring into the trimmer head. Push the spool down into the trimmer head. Lock them in place by tightening the cap clockwise.