Installation manual
ALTERNATORS
TESTING/TROUBLESHOOTING
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.
1.
Start
the Engine.
2. After the engine
has
run for a few minutes, measure the
starting
battery voltage at the battery termin'lls using a
multimeter set on DC volts.
a.
If
the voltage
is
increasing toward 14 volts, the
alternator is working.
b.If
the voltage remains around
12
volts, a problem
exists with either the alternator or the charging circuit;
continue with
Steps 3 through 6.
MEASURING
BATTERY
VOLTAGE
(ENGINE
RUNNING)
3.
111m
otT
the
engine. Inspect all wiring and connections.
Ensure that the
battery terminals and the engine ground
connections are tight and clean
4.
If
a battery selector switch
is
in the charging circuit,ensure
that it
is
on the correct setting.
S.
111m
on
the
ignition switch,
but
do
not
start
the
engine.
6. Check the
battery
voltage.
If
your battery is in good
condition the reading should
be
12
to
13
volts.
MEASURING
BATTERY
VOLTAGE
(IGNITION
ON
ENGINE
TESTING
THE
OUTPUT
CIRCUIT
1. Connect the positive probe to the output terminal
Band
connect the negative probe to ground.
2. Wiggle the engine wiring harness while observing the
voltmeter. The meter should indicate the approximate
battery voltage, and should not vary.
If
no reading is
obtained,
or
if
the reading varies, check the alternator
output
circuit
for
loose
or
dirty connections
or
damaged wiring.
3.
Start
the
engine.
4. Repeat the same measurement, the negative probe to
ground, the positive probe to B with the engine running.
The voltage reading should
be
between 13.5 and 14.5
volts.
If
your alternator is over
or
under-charging, have
it repaired at a reliable service shop.
S.
If
the previous test reads only battery voltage at
terminal B, use the meter to measure the DC excitation
terminal.
If
12 volts is not present at exciter terminal
R,
inspect the wiring for breaks and poor connections.
Jump 12 volts from a
12
volt source (such as the
battery) and operate the alternator.
If
the voltage output
is 13-14 volts,
..
then the alternator is OK.
TESTING
THE
OUTPUT
CIRCUIT
ENGINE
RUNNING
#10
ORANGE
B
TO
STARTER
~UU'NOIU-f~~~1!
#16
VIOLET
R
.TERNIINALR
Engines & Generators
TO
K·3
RELAY
#16
REO
TO
ACTUATOR
25