1986+ Mercury 6/8/9.9/10/15HP 2-stroke Factory Service Manual, Page 73Get this manual
CHARGING AND STARTING SYSTEM
(1999 And Newer)
The battery charging system components are the alternator, rectifierregulator and the batteryAlternating current (generated in the alternatorstator coils) flows to the rectifierregulator, which changes the alernating current ot direct current for charging the battery
aAlternatorTachometer moduleTachometer leadGround leadsRectifierRegulator The charging system may be damaged by: aReversed battery cablesbRunning the engine with battery cables disconnected and alternator leads connected to rectifiercAn open circuit, such as broken wire or loose connection
Alternator Amperes Output 1999 And Newer (Stator10 Pole5 Pulse)
Amperage output can be measured by installing amp meter (10 amp minimum) in series between the rectifier and the battery or by clamping an inductive type amp meter (10 amp minimum) over the RED output lead from the rectifier to the battery