2004 SR Johnson 2-stroke 40, 50HP Service Manual, Page 82Get this manual
ELECTRICAL CHARGING SYSTEM COMPONENTS
CHARGING SYSTEM COMPONENTS
The charging system consists of battery, flywheel, alternator stator, and rectifier
Flywheel
The engine's flywheel contains permanently charged magnetsThe magnets supply energy to power the stator windingsThe magnets must be at their original design strength for full alternator output
RectifierReg lator
Four amp rectifiers consist of series of diodes, built into metal case, which changes the stator's alternating current to the direct current used to charge the battery31276