Komatsu 830E-AC Shop Manual page 244

PERIODIC MAINTENANCE
Alternator performance depends on the condition of
the components in the charging system. The most
important components in the charging system are the
alternator drive belt, battery, and related cables and
connections. A loose drive belt, weak battery, or cor-
roded cables and connections can cause the alterna-
tor to work extra hard, leading to overheating and a
reduction in performance. When performing any
scheduled maintenance on your vehicle, ensure
these components are working properly. The alterna-
tor itself requires little maintenance.
1. The most important maintenance requirement
for an alternator is to keep the air cooling pas-
sages free of dirt and obstruction.
2. To ensure that air cooling passages are clean,
the alternator can be washed using a garden
hose.
3. During washing, avoid spraying high pressure
water directly on the regulator and regulator
connector. This can cause moisture to get past
the seals in the connector and cause perfor-
mance problems.
4. After washing, dry the alternator by operating
the engine and alternator a few minutes. Main-
tenance requirements for internal components,
such as alternator bearings, depend on the
application, usage, and environment.
D10-14
TESTING
GENERAL INFORMATION
Troubleshooting Alternator (On-Truck)
Most 24-Volt charging system problems can be diag-
nosed with the alternator installed on the truck, oper-
ating under normal conditions. Many problems can
be attributed to loose or corroded cable connectors.
It is essential that all battery charging cables are in
satisfactory condition and all connections are clean
and securely tightened.
Equipment Required
• Voltmeter, 0-40 Volt range (Digital type preferred)
• Ammeter, 0-400 amp range (Digital, inductive
type preferred)
• Jumper wires
Preliminary Checks
Ensure that an undercharged battery condition has
not been caused by accessories having been left on
for extended periods.
1. Check the alternator drive belt.
2. Ensure the automatic belt tensioner is working
correctly.
3. If a battery defect is suspected, check the bat-
tery.
4. Inspect the wiring for defects. Check all connec-
tions for tightness and cleanliness. Remove and
clean the battery cables.
5. The truck is equipped with a battery equalizer
system. Verify the proper operation of the
equalizer and the individual battery voltages.
Refer to Battery Equalizer, Section D, 24VDC
Electrical Supply System.
6. Check the (B-) cable, (B+) cable, and alterna-
tor-to-regulator wiring harness connections.
Repair or replace any damaged component
before troubleshooting.
7. Ensure the thermal switch is functioning properly.
Refer to the Thermal Switch section in this chap-
ter for additional information.
Battery Charging Alternator D10003 07/06