The images of the carb adjustment pages are rather large so I convert to a two page PDF.
https://1drv.ms/b/s!AhP6VW6j_ZC5i2q2CYupxwyZBHu0?e=VheASmNOTE: max engine no load speed is 10,500 rpm with an idle speed of 2800 rpm. Plus this unit does have a clutch so if the head is still spinning at idle either the idle speed is too high or the clutch has a failure. Springs are known to break.
As for the possible flooding check the metering diaphragm, lever height, and needle valve. Also don't forget to check the spark arrester screen.
If you PM me your email address I can send you a couple links to the SM and IPL. Just don't want Stihl crawling me for having them since they are dealer only items.
Just no telling what carburetor Stihl now has for this unit, changes over time.
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