Evinrude & Johnson E75DPLSCB, Service Manual

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127
ELECTRICAL AND IGNITION
CHARGING SYSTEM TESTS
7
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 there is battery voltage on the
connector red wire when key is ON.
Disconnect the battery cables at the battery.
Use an inductive amp meter or connect a 0 to
50 A ammeter in series between the red wire
s 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 battery cables.
Following the manufacturer’s directions, connect
the variable load tester (carbon pile) across the
battery terminals.
Stevens model LB-85 and
Snap-On model MT540D are examples of testers
available.
WARNING
Excessive battery discharge rates might
overheat battery causing electrolyte gas-
sing. This might create an explosive atmo-
sphere. Always work in a well ventilated
area.
Variable Load Test Diagram
1. Red wire (alternator output from EMM )
2. Starter solenoid
3. Battery cable terminal (B+)
4. Variable load tester
5. Ammeter
002077
Battery Charging Graph
002076
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