Having trouble keeping my cj2a running. It will fire up strong then sputter out. I have replaced the points, condenser, rotor, cap, wires plugs and resent the timing.ran great for a couple days then all of a sudden this problem started. It acts like it can't burn the fuel or it stops creating spark. I have watched the point as I turn the engine and seems to create good contact and spark. Am I missing something ? I have spark, fuel and air. Any ideas would be helpful. Thanks