Service Manual

Alternator Current Output
1. Disconnect the battery ground (–) cable.
2. Install an ammeter between the positive (+) terminal
of the battery and terminal
”B” of the alternator.
3. Ground alternator terminal ”B”
through a voltmeter.
4. Connect the battery ground (–
) cable.
5. Check to make sure voltmeter reads battery voltage.
I
f voltmeter reads 0 V, check for open circuit between al-
ternator ”B” terminal and battery (–) terminal, a blow fus-
ible link or poor grounding.
NOTE: After starting the engine, charging current drops
quickly
. The following step must be done quickly to read
maximum current value correctly.
6. Turn on all electrical loads, start the engine, quickly
r
un up to 2500 rpm and read maximum indication on am-
meter. Reading should be higher than limit value.
Ammeter
+
_
+
_
Charging
indicator
Load
L
B
G
Battery
Ignition
Switch
Voltmeter
Figure 67
Limit 28 A
NOTE: Nominal output is shown on name plate affixed
to alternator body. Output current changes with electri-
cal load and temperature of alternator. Nominal output
current may not be obtained if electrical load at time of
test is small. Before testing, turn on headlights while ve-
hicle is not running to partially discharge battery.
Liquid Cooled
Gas Engine
Workman 3000/4000 Series Page 3 – 45 Liquid Cooled Gas Engine