1970 Johnson 1.5 HP Outboard Motor Service Manual, Page 25Get this manual
BREAK ER ARM
MAGNETO system consists of flywheel type magneto connected to the spark plug through high tension leadmagneto is selfcontained electrical generating unit consisting of an armature plate with one coil and lamination assembly, condenser, and breaker assemblypermanent magnet cast into the flywheel completes the assemblyTHEORY OF
The magneto employs the interaction of the fast moving flywheel magnet and stationary to generate an electric current of voltage sufficient to across the spark plug air gapThis creates the spark that ignites the fuel in the cylindercoil actually consists of two coilsOne, called the primary, consists of relatively few turns of heavy gage copperwireother, called the secondary, consists of many turns of fine gage wirecoils separated insulation and mounted the center leg of an shaped laminated iron
Figure Magneto Armature Plate