Re: Big Twin 40 safety switch wiring question

[frankr]

That is all wrong.
One white wire goes to the safety switch.
Other white wire goes to one of the small terminals on the start solenoid.
The other small terminal on the start solenoid goes to the "S" terminal on the key switch.
You must have the correct solenoid for this to work. A car solenoid won’t get it. In fact, a car solenoid will destroy the safety switch.

One of the black wires on the center post of the vacuum switch goes to the points.
Another black wire goes from that same center post to one of the "M" terminals on the key switch.
The other "M" terminal on the key switch goes to the other set of points.
The two "M" terminals function as a kill switch to stop the motor when switch is turned off.