the low speed needle adjustment will make it not start if the initial setting is way off.. turn it clockwise until you feel it just start to seat and then turn it back out about a full turn give or take and it should start but then youll need to fine tune it on the water to get your idle at the right rpm's, make very small adjustments either clockwise or counterclockwise and give the motor about 15-30 seconds for each adjustment so the fuel and air will get in the motor.. are you sure the motors not getting fuel? how did you check your spark? holding the plug to the head and turing the motor over to check spark is a waste of time because even if you see spark doesent mean its strong enough to combust fuel, u need to buy a spark tester (under 10 buck) or make one to properly check it. when motor wont start always start at the fuel tank and check everything from there to the carb, check the hose to the primer bulb(if u have one), hose to the motor, fuel pump and carb. if your for sure not getting gas to the motor then you know its the carb causing the problem, if not the carb then start checking ignition coils,power pack,stator,charge coil, plate etc....