Service and Repairs

48
Electrical System
KohlerEngines.com 17 690 01 Rev. L
To test charging system for no charge to battery:
1. Separate bullet connector in white lead from rectifi er-
regulator. Connect an ammeter from female terminal
to positive (+) terminal of battery. Connect a DC
voltmeter from female terminal to negative (-)
terminal of battery. Leave other rectifi er-regulator
leads connected in normal manner. Run engine at
3600 RPM and read voltage on voltmeter.
If voltage is 14.0 volts or more, place a minimum
load of 5 amps (turn on lights if 60 watts or more, or
place a 2.5 ohm, 100 watt resistor across battery
terminals) on battery to reduce voltage. Observe
ammeter.
Condition Conclusion
Voltage is 14.0-15.0 volts
and charge rate increases
when load is applied.
Charging system is OK
and battery was fully
charged.
Voltage is less than 14.0
volts or charge rate does
not increase when load is
applied.
Test stator (steps 2 and
3).
2. Separate bullet connectors in AC (white) leads.
Connect an AC voltmeter across stator leads (female
terminals). With engine running at 3600 RPM,
measure AC output from stator.
Condition Conclusion
Voltage is 20.0 volts or
more.
Stator is OK. Rectifi er-
regulator is faulty; replace.
Voltage is less than 20.0
volts.
Stator is probably faulty
and should be replaced.
Test stator further using
an ohmmeter (step 3).
3. With engine stopped, measure resistance from each
stator lead to ground using an ohmmeter.
Condition Conclusion
Resistance is infi nity
ohms (no continuity).
Stator is OK (not shorted
to ground).
Resistance (or continuity)
is measured.
Stator leads are shorted to
ground; replace.
To test charging system for battery continuously charging
at high rate:
1. Separate bullet connector in white lead from rectifi er-
regulator. Connect an ammeter from female terminal
to positive (+) terminal of battery. Connect a DC
voltmeter from female terminal to negative (-)
terminal of battery. Leave other rectifi er-regulator
leads connected in normal manner. Run engine at
3600 RPM and read voltage on voltmeter.
If voltage is 14.0 volts or more, place a minimum
load of 5 amps (turn on lights if 60 watts or more, or
place a 2.5 ohm, 100 watt resistor across battery
terminals) on battery to reduce voltage. Observe
ammeter.
Condition Conclusion
Voltage is 15.0 volts or
less.
Charging system is OK.
Battery is unable to hold a
charge; service or replace.
Voltage is more than 15.0
volts.
Faulty rectifi er-regulator;
replace.
3/4/10/18 Amp Battery Charging Systems
NOTE: Zero ohmmeters on each scale to ensure accurate readings. Voltage tests should be made with engine
running at 3600 RPM - no load. Battery must be fully charged. Check specifi c gravity of battery. If low,
recharge or replace battery as necessary.