Re: ignition switch wiring diagrams
This is way my '75 115 Johnnie works and the diagrams above are consistant with mine.
The kill circuit takes primary voltage from the engine to the ignition switch. The igniton switch grounds the primary voltage to kill the engine. The primary voltage is not battery dependent, it is generated in the engine. The kill switch, too, grounds the primary power.
Thus, any ground in the wiring between the engine and the switch will drain current and no secondary volt will be generated. Removing the ignition wiring from the power pack will allow the engine to start if there is a problem in this circuit. However, you will have to rig a temp ground wire to touch to the terminal to kill the engine or cut off the air or fuel. Or use and ohm meter to check for grounds.
The kill switch circuit by passes the ignition switch wire to ground. Could be a problem here to if a errant ground exists.
Again, on mine, the primary voltage to the ignition switch is something like 300 volts and will give you a smart tingle, I know. Thought I was hit with spark voltage. So, it is pretty easy for it to find a ground if the circuits are not well insulated or track past dirty/wet/loose teminals.