ELECTRICAL and IGNITION - 2A-190-817643R1 DECEMBER 1996
Description
The outboard ignition system is alternator-driven with dis-
tributor-less capacitor discharge. Major components of the
ignition system are the flywheel, stator, trigger, switch box,
ignition coils and spark plugs.
The stator assembly is mounted stationary below the fly-
wheel and has 2 capacitor charging coils. The flywheel is
fitted with permanent magnets inside the outer rim. As the
flywheel rotates the permanent magnets pass the capaci-
tor charging coils. This causes the capacitor charging coils
to produce AC voltage. The AC voltage then is conducted
to the switch box where it is rectified and stored in a capaci-
tor.
The trigger assembly (also mounted under the flywheel)
has 3 coils. The flywheel has a second set of permanent
magnets (located around the center hub). As the flywheel
rotates the second set of magnets pass the trigger coils.
This causes the trigger coils to produce an AC voltage that
is conducted to an electric Silicon Controlled Rectifier
(SCR) in the switch box.
The switch discharges the capacitor voltage into the igni-
tion coil at the correct time and firing order sequence.
Capacitor voltage is conducted to the primary side of the
ignition coil. The ignition coil multiplies this voltage high
enough to jump the gap at the spark plug.
The preceding sequence occurs once-per-engine-revolu-
tion for each cylinder.
Spark timing is changed (advanced/retarded) by rotating
the trigger assembly which changes each trigger coil posi-
tion in relation to the permanent magnets on the flywheel
center hub.
IMPORTANT: If the engine misfires, runs rough or does
not start, the ignition system should be checked using
a Multi-Meter/DVA Tester (91-99750), or a voltmeter
(capable of measuring 400 volts DC, or higher) and Di-
rect Voltage Adaptor (91-89045).
Test Procedures
Direct Voltage Adapter (DVA) Tests
! WARNING
DANGER – HIGH VOLTAGE/SHOCK HAZARD! Do not
touch ignition components and/or metal test probes
while engine is running and/or being “cranked”. STAY
CLEAR OF SPARK PLUG LEADS. To assure personal
safety, each individual spark plug lead should be
grounded to engine.
!
CAUTION
To protect against meter and/or component damage,
observe the following precautions:
– 400 VDC* test position (or higher) MUST BE used for
all tests.
– INSURE the Positive (+) lead/terminal of DVA is con-
nected to the Positive (+) receptacle of meter
– DO NOT CHANGE meter selector switch position
while engine is running and/or being ”cranked”.
– Switch box MUST BE GROUNDED during tests.
Running or ”cranking” engine with switch box un-
grounded may damage switch box.
*If using a meter with a built–in DVA, the DVA/400 VDC test
position should be used.
NOTE: Test leads are not supplied with the DVA. Use test
leads supplied with meter.
Test procedures and specifications are provided for check-
ing primary ignition voltage while the engine is running
and/or being ”cranked”.
TROUBLESHOOTING TIPS:
1. Intermittent, weak, or no spark output at two spark
plugs usually indicates a bad TRIGGER.
2. Intermittent, weak, or no spark output at all three spark
plugs usually indicates a bad STATOR or SWITCH
BOX.
3. Intermittent, weak, or no spark at any one spark plug
usually indicates a bad SPARK PLUG, COIL, or
SWITCH BOX.
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