Duraspark II distributor Pick Up Coil. Should the finned wheel under the rotor be able to spin freely on the shaft? I have a misfire and surge like starving for fuel but besides the carburator and tanks I have gone over the fuel system that I can get to, and have looked at the vacuum lines nothing loose or missing. Carb is tight. New fuel pump.
That's the "reluctor" and it must not be loose on the shaft. That very precisely sets ignition timing. Some systems have an adjustable air gap between the reluctor and pickup coil and that gap is critical.