1) Has the carburetor been rebuilt recently? If not, put a diaphragm kit in it. Remove the pump cover(aluminum) Check the fuel inlet screen for debris. check that the hose attached to the pump cover goes to the crankcase fitting.
2) set the H needle to 1/4 turn(for pipe) and the L needle to 2 turns. With these settings the engine will not idle. You can make a KT idle by setting the L needle to 1/2 – 3/4, however there is not enough fuel at 3/4 to get out of the pits.
3) Use Race gas like VP or ERC (100 octane). and mix 8 ounces of castor oil(Blendzall green label) to 1 gallon.
4) Install a new fuel filter, watch the arrow for direction.