FS90 is a partial model number for a Stihl String Trimmer. To see specific parts for your String Trimmer, please choose your exact model from the list below or choose the model that’s closest.
For the symptom you selected, these are the most common parts or causes, ordered by the likelihood of fixing the symptom.
If the string trimmer head won't spin the head may have separated from the drive shaft. Disassemble the head to determine the cause.
Choose your model number to see parts for your string trimmer.