1993 Johnson Evinrude "ET" 2 thru 8 Service Manual, P/N 508281, Page 128Get this manual
Principles of Operation3, 4 Flywheel
r.jl The flywheel
L.J the sensor coil and ignition moduleOnce the flywheel exceeds minimum cranking RPM, the flywheel 's magnetic lines of force pass through the ignition plate components to produce voltage in those circuitsThe flywheel must be in good condition and correctly located to ensure proper ignition timing and sufficient ignition module outputSensor Coil
contains permanent magnets which energize
r.jl The sensor coil consists of many windings of wire wrapped
L.J 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 ignition moduleIgnition Module The ignition module
has four basic functions:
The ignition module has an internal charge coil that produces approximately 200 volts of alternating current The ignition module converts charge coil alternating current to direct current The ignition module stores the direct current in capacitor The ignition module directs the capacitor output to the ignition coil primary windings through series of tronic switches (SCR's)The SCR's select the correct ignition coil primary winding by sensing the polarity of the sensor coil outputStop Circuit