Carb ajustments should be carried out by somebody with an engine rev counter, exceeding the max free running speed can result in engine seizure, the H screw is like a govenor it controls the max rpm, there is no way of settings this by ear, i am all for end useres repairing and serviceing there own kit, but this could turn into a very expensive adjustment.
Husqvarna man
March 2010
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