To adjust the carburetor on Poulan chainsaws, clean the air filter and the spark arrestor, and adjust the adjustment screws marked T, L and H to set the idle and engine speed. Preferably, have the H and L screws adjusted by a professional.
Begin adjusting the carburetor on a Poulan chainsaw by undoing the retaining nut of the cover of the air filter by hand. Then, take out the cover and air filter, and clean the latter using soap and water. If required, replace the filter.
Then, take out the cover of the cylinder to access the spark arrestor located at the back of the muffler, and pull the arrestor out. Clean the arrestor's screen using a wire brush. Now, refit the arrestor and filter, and switch on the chain saw's engine.
If the engine does not operate continuously, rotate the screw marked T or the idle screw by one clockwise turn using a screwdriver with a slot. If this puts the engine on idle very quickly, turn the screw counter-clockwise soon after the saw begins to function.
Next, position the chainsaw on an even surface, keep things away from the chain, and switch on the engine. Check if the chain is turning when the saw is on idle. If so, turn the idle down until the chain ceases to turn. Also, note the setting at which the engine functions normally and continuously.
To adjust the H and L or high and low-speed screws, follow the specifications of the manufacturer, and use a tachometer to measure the speed of the engine when rotating the screws. If the chainsaw manual does not contain the specifications, have the screws adjusted by an authorized technician.