Did you correct the problem? If not, the ignition switch is a good suspect. On a 6 volt system, there is no start-bypass circuit, so if the ignition switch has resistance, the coil gets low voltage and reduced current. Remember, those old engines can be started with a hand crank; that cranking speed is much slower than the worst starter- as long as the engine cranks at all. Since you say the engine starts almost immediately with a push, I suspect the ignition switch is at fault.
Harvester
