Chainsaw Repair

Yes the low speed fuel circuit provides fuel at wot. And a change in the low speed circuit will affect the fuel volume over the high speed as well. For example if you lean out the low speed then the whole fuel/air mixture will be leaner on the high and low speed. I would start and make sure the throttle lever is closing all the way to the screw. Have seen carbs new from the box the either the throttle or choke plate was not installed correctly and the plates would not seal in the bore of the carb. Had to loosen the screws and turn the plates to get them seated properly. Your basic carb setting should be 1 full turn out from a seated position. On both the high and low speed screws the idle screw I have found that 2.5 turns out from all the way in is a good place to start. You may also what to go with 1.25 turns out on the high and low speed it should be a fairly rich setting but should get you going.