How do you fix a stihl gas trimmer?

Stihl does not make parts or service available at their website though dealers have secure access through a different site also availble to students through applying for guest access.

One site has a few manuals available. The line trimmers are FS models with three engines used in recent years; the 4137, 4140 and 4180. Hedge trimmers are HS model with comparable engines though the crankshaft is often applicatio-specific.

Check the link below.