1 Answer

(LA) Idle Speed screw - This controls the engine speed at idle. If set too low, the saw will die. If set too high the chain will run. This is dangerous.

(L) Low speed adjustment screw - This is the low speed jet. This is the adjustment that controls the air/fuel mixture at idle. Adjust this screw too rich and the chainsaw will blubber and die at idle speed. Adjust this screw too lean and the engine will starve. The saw will race or surge. An extremely lean adjustment will also cause the engine to die.

(H) High speed adjustment screw - This is the high speed jet. This is the adjustment that controls the air/fuel mixture at high RPMs. Adjust this screw too rich and the chainsaw will blubber, too lean and it will over rev 

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