Home › Forum › Ask A Member › 1964 Johnson 40 hp Ignition System & Airguide Tach Compatability › Re: 1964 Johnson 40 hp Ignition System & Airguide Tach Compatability
June 24, 2015 at 11:03 pm
#18851
The two black wires going to your key switch "M" terminals connect to the "primary" side of the magneto coils.
Either should do.