1995 Johnson Evinrude "EO" 9.9 thru 30, 2-Cylinder Service Manual, P/N 503146, Page 111Get this manual
Principles of Operation Flywheel
r:;-J The flywheel contains permanent magnets which energize charge coil, sensor coil, and alternator statorOnce the flywheel exceeds minimum cranking RPM, the flywheel's magnetic lines of force pass through the ignition plate components to produce voltage in those circuits
The flywheel must be in good condition and correctly located to ensure proper ignition timing and sufficient charge coil outputCharge Coil
f2l The charge coil consists of many windings of wire wrapped
t=.l around metal laminationOnce the flywheel exceeds a
minimum cranking RPM, the flywheel's magnetic lines of force pass through the charge coil windings to produce approximately 300 volts of alternating currentThis voltage is supplied to the power pack to operate the systemSensor Coil
f2l The sensor coil consists of many windings of wire wrapped t=.l around metal laminationOnce the flywheel exceeds a
minimum cranking RPM, the flywheel's magnetic lines of force cutting through the sensor coil windings produce approximately voltsThis voltage is supplied to the power pack to control small electronic switches (SCRs) which, in turn, direct power pack output to the correct ignition coil primaryPower Pack