When changing the line on your Stihl string trimmer, always be sure to use the correct type of recommended nylon line. There are specific thicknesses for each size and type of string trimmer, from consumer to professional models, and the thickness will always be marked on the trimmer spool itself. Using either a thicker or thinner line than what is recommended will not allow the proper feeding of the line, so always use the correct thickness of line for the best trimming and hassle free results.
Remove the spool from the string trimmer hub by either pushing in side tabs that hold the spool on, or unscrewing a center nut by hand. No special tools are required for this task on a Stihl string trimmer.
Locate the line size which will be printed or embossed onto the spool proper. Common types are 0.80 and 0.95. Get the one that is made for your spool.
Insert the new line into the line anchor hole inside of the spool. Stihl spools are user friendly and will have an arrow that points specifically to this hole.
Begin winding the line counterclockwise. On the spool there will be arrows showing which way the line needs to be wound. Follow the arrows and wind the line accordingly.
Continue winding the line until the spool is almost full.
Clip the line with your shears or scissors, then hold the clipped end with your fingers or the spool will unravel.
Place the spool back into the weed trimmer hub, and thread the clipped end through the exit port hole in the hub. Allow about 6 to 8 inches of line to extend from the exit port. Press the spool back into the hub and secure it with either the push tabs or the plastic nut.