Installation manual
DC
ELECTRICAL
SYSTEM
ALTERNATOR
The charging system consists
of
a DC belt driven alternator
with a voltage regulator, an engine
DC
wiring harpess, a
mounted DC circuit breaker and a battery with connecting
cables. Because
of
the use
of
integrated circuits (IC's), the
electronic voltage regulator is very compact and
is
mounted
internally or on the back
of
the alternator.
50
AMP
ALTERNATOR
ALTERNATOR
TROUBLESHOOTING
A
WARNING:
A
failed
alternator
can
become
very
hot.
Do
not
touch
until
the
alternator
has
cooled
down.
Use this troubleshooting section to determine
if
a problem
exists with the charging circuit
or
with the ·alternator.
If
it is
determined that the alternator or voltage regulator
is
faulty,
have a qualified technician check it.
The alternator charging circuit charges the starting battery
and the service battery.
An isolator with a diode, a solenoid
or a battery selector switch is usually mounted in the circuit
to isolate the batteries so the starting battery is not discharged
along with the service battery.
If
the alternator is charging the
starting battery but not the service battery, the problem
is
in
the service battery's charging circuit and not with the
alterna-
tor.
Testing
the
Alternator
A
CAUTION:
Before
starting
the
engine
make
certain
that
everyone
is
clear
of
moving
parts!
Keep
away
from
sheaves
and
belts
during
test
procedures.
A
WARNING:
When
testing
with
a
multimeter:
DC
und
AC
circuits
are
often
mixed
together
in
marine
applications.
Always
disconnect
a
shore
power
cord,
isolate
DC
and
AC
converters,
and
shut
down
the
engine
before
performing
DC
testing.
No
AC
tests
should
be
made
without
a
proper
knowledge
of
AC
circuits.
1.
Start the engine.
2. After the engine has run for a few minutes, measure the
starting battery voltage at the battery terminals using a
multimeter set on DC volts.
a.
If
the voltage
is
increasing toward 14 volts, the alterna-
tor
is
working; omit Steps 3 through 8 and
go
directly
to
"Checking the Service Battery" on the next page.
b. If the voltage remains around
12
volts, a problem
exists with either the alternator or the charging circuit;
continue with Steps 3 through
8.
MULTIMETER
TESTING
THE
STARTING
BATTERY/ALTERNATOR
(ENGINE
RUNNING)
miD
0
COM
3. Turn off the engine. Inspect all wiring and connections.
Ensure that the battery terminals and the engine ground
connections are tight and clean.
A
CAUTION:
To
avoid
damage
to
the
battery
charging
circuit,
never
shut
off
the
engine
battery
switch
when
the
engine
is
running!
4.
If
a battery selector switch is in the charging circuit,
ensure that it is on the correct setting.
5. Tum on the ignition switch, but do not start the engine.
6. Check the
battery voltage.
If
the battery
is
in good condi-
tion, the reading should be 12 to
13
volts.
TESTING
THE
ALTERNATOR
VOLTAGE
(IGNITION
ON
·
ENGINE
OFF)
GZID
~~--MULTIMETER
Engines & Generators
-="
GROUND
22