The only thing that comes to mind is the fuel pump is bad and the arm, if you will, will not move, as the lobe on the camshaft is in the outer position. If the arm on the fuel pump will not move, than I could see the pump not sitting flush. But if the arm moves okay, the only other thing I could think of is the pump is hitting the plug under it. You know the one that is there that you have to take out to put the rod in that goes from the cam to the fuel pump. All that I can think of, hope that helps.