a wiring diagram for 1960-1965 Johnson 40hp - review

arnfayn1

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I am reviewing wiring diagram for 1960-1965 Johnson 40hp . We can see that the wire came from ?M? terminal of the key switch to the cylinder coil (It is not "M" terminal to kill engine). This coil will be powered by 12v continually and be fired. Can somebody to answer for this question?
 

Chris1956

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Re: a wiring diagram for 1960-1965 Johnson 40hp - review

I thought all those motors were magneto ignition. The magnets of the flywheel produces all the voltage necessary to fire the spark plugs. The magneto ign coils were shorted to each other to kill the spark.
 

arnfayn1

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Re: a wiring diagram for 1960-1965 Johnson 40hp - review

Thank you Chris for reply.
I understand how it working.
However, I do not understand why coil powered all time by 12v.
______
?M? terminal o--------| coil |----------o ?Ground?
-------
If we put on the coil in the circuit with 12v it will be broken after few minuts.
 

Chris1956

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Re: a wiring diagram for 1960-1965 Johnson 40hp - review

One side of the coils should be grounded to a screw under the flywheel. The other side should be connected to one of the M terminals. Ditto for the other coil. Maybe your ign switch is putting voltage onto the coils?
 
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