Almost half turn all carburetor models have three adjusting screws. The screw (T) is responsible for fine-tuning in idle speed mode. Marked (H) screw setting the operation at maximum speed. The marked (L) regulates the formation of the mixture at low rpm. By tightening the marked (L) screw and marked (H) screw, the fuel supply and the mixture are depleted, respectively, and the speed increases. If you still have questions about your chainsaw, check out the manufacturer's website in FAQ section. And please, let me know in the comments if you succeeded in setting up your Poulan Chainsaw Carburetor, maybe your experience will help newbies.