How to Rewind a Stihl Trimmer Head
- 1). Unplug the trimmer if you are using an electrical model. For a gas model, disconnect the spark plug, which is located on the exterior of the engine housing at the top of the tool. Removing the power source will ensure that the machine cannot accidentally activate while you work on it.
- 2). Hold the head of the string trimmer steady in one hand and grasp the head cap in the other. Turn the cap counterclockwise until it comes off and set the cap aside.
- 3). Gently pull the spool out of the trimmer head. Remove any remaining nylon line. Wipe down the spool and the interior of the head with a damp rag to remove grass or dirt.
- 4). Set the spool back into place in the trimmer head. If your model features a spring, make sure the spring stays attached to the spool at all times. Rotate the spool until the two arrows on each side of the spool are in line with their corresponding arrows on the trimmer head; this will reveal two small holes in the head.
- 5). Cut two pieces of 0.080-inch mowing replacement line, each piece measuring 6 feet 6 inches long. Use a sharp utility knife or wire cutters to cut through the line.
- 6). Thread one end of each replacement line into one of the holes, so that each line has its own hole. Push until you cannot push anymore.
- 7). Hold the trimmer head steady in one hand. With the other hand, rotate the spool counterclockwise; this will wind the replacement line into the head and around the spool. Continue to rotate until the lines each have about 4 inches remaining on the ends.
- 8). Replace the cap onto the mowing head. The trimmer is now ready to use.
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