Working on a Ford NAA that has sat some. I put new plugs, wires, distributor cap, rotor, and battery on tractor. It's still 6 volt. Took sediment bowl off, drained tank, tank is clean. Cleaned up sediment bowl, cleaned filter going into carburetor. I have good gas flow to the carburetor. Took carburetor off and rebuilt it. Carb was clean inside when I took it apart, but I went ahead and put a rebuild kit in it, the power jet that goes under nozzle was not there??? Don't know if that is my problem? Tractor runs, but wants to surge some. Tractor seems to run smoothest with idle needle turned all the way in? Thanks for your help.