L is low speed mixture, H is high speed. Start the saw, idle when warm and screw the L adjuster in until the saw falters then screw out until the best tickover is achieved - adjust the tickover so the chain doesn't turn. Rev the knackers off it and adjust the H setting, screw in or out until a slight faultering or burbling is heard and this is a slightly rich mix which will stop seizure.
Steve, February 2009
