2002/2003 Johnson SN/ST 2 Stroke 3.5, 6 8 HP Outboards Service Manual, PN 5005466, Page 68Get this manual
ELECTRICAL RUNNING ALTERNATOR OUTPUT TEST68 Install starwasher on the threaded battery post, the wire from the outboard, and the cables from accessories lastFinish this connection with hex nut
RUNNING ALTERNATOR OUTPUT TEST68
Disconnect battery cables before proceeding with this checkRemove the rectifier red lead from the terminal boardWire 0-40 amp ammeter in series with the rectifier red lead and the wiring harness red lead&Marine style battery post 1Starwasher 2Hex nut
WARNING
IMPORTANT: Do not use wing nuts to fasten ANY battery cablesWing nuts can loosen and cause electrical system damage not covered under warrantyTighten all connections securelyApply Triple Guard grease to prevent connections from corroding
Guard against any red wire, its terminals, or the ammeter coming in contact with engine ground while the engine is runningContact could cause arcingThe engine's battery should not be fully charged when beginning this testConnect the battery cables and run the engine in test tankRefer to the output curves to determine the correct outputto-RPM ratio for your engine