Wiring AC-B that has magneto and alternator.

• Duey's web site

I assume you are talking about a three wire, internally regulated alternator like the Delco 10SI. I don't know about that particular NAPA switch because I used a DPDT two position toggle switch instead. In the "off" position the magneto stud needs to be connected to ground through the switch while at the same time the #1 control terminal on the alternator needs to be disconnected from battery + voltage. In the "on" position the magneto stud needs to be opened to ground through the switch while at the same time the #1 control terminal on the alternator needs to be connected to battery + voltage (through a low amperage fuse). If you want to use your key switch to also energize the starter you will need to add a 12v starter solenoid that gets energized when the switch is in the momentary "start" position. I use a separate two position, normally open push button switch for starting.

You will need to use a continuity tester to see exactly which terminals on your particular switch make and break contact in the different switch positions.

Rod