Evinrude E-tec 75 HP, Service Manual

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ELECTRICAL AND IGNITION
CHARGING SYSTEM TESTS
Capacitor Test
The capacitor should charge when you use an
ohmmeter on the high ohms scale with the proper
polarity. The resistance will increase until it goes
to (nearly) infinity. If the capacitor is shorted, then
it will never charge. If it is open, the resistance will
be infinite immediately and won't change. If the
polarity of the probes is reversed, it will not charge
properly either. Determine the polarity of your
meter and mark it. Black is usually negative with
VOMs, for example. Confirm with a marked diode.
A low reading across a good diode indicates that
the positive lead is on the anode (triangle) and
negative lead is on the cathode (bar).
CHARGING SYSTEM
TESTS
12 V Charging Circuit
To test the operation of the regulator in the
EMM
,
you must be able to run the outboard continuously
at approximately 5000 RPM, such as in a test tank
or on a marine dynamometer.
The test consists of monitoring the system’s
response to a partially discharged battery. Use a
variable load tester to discharge the battery.
IMPORTANT:
The regulator requires battery
voltage on the red wire to operate. Before pro-
ceeding, make sure battery voltage is at the con-
nector red wire when key is ON.
Test Procedure
Disconnect the battery cables at the battery.
Use an inductive amp meter or connect a 0 to
40 A ammeter in series between the red wire of
engine wire harness (alternator output from
EMM
)
and the positive (B+) battery cable terminal of
starter solenoid.
Fluke
† model 334 or 336,
Snap-On
† model MT110
or EETA501, and various other amp meters
should be available through local tool suppliers.
Reconnect the outboard’s battery cables.