Specifications
56
3 Amp D.C. 5 Amp A.C. Alternator
Models: OVM/OVXL 12.5, OHV12.5-18.0, OV358,
OV490
This unit combines a 3 Amp D.C. system used to charge
a battery and a 5 Amp A.C. system used for lighting.
Located in the red wire of the harness is a diode which
converts the alternating current to direct current for
charging the battery. The yellow wire provides the A.C.
voltage for the lighting circuit.
A wire harness (part #36588) may be added to the 3
Amp D.C./5 Amp A.C. charging system to power an
electric clutch without the use of a battery. Test the
diode in the harness by doing a continuity test (diag.
104).
Replace the diode if continuity exists after reversing
tester leads or if no continuity is found.
CHECKING THE SYSTEM: To check the system,
disconnect the plug and measure the D.C. voltage at the
red wire terminal (diag. 105). Measure the A.C. voltage
at the yellow wire terminal. With the engine running the
minimum values should be: (diag. 106)
Models OVM/OVXL/OHV
3 Amp D.C. (Red wire)
2500 R.P.M. - 8.0 Volts D.C.
3000 R.P.M. - 11.0 Volts D.C.
3600 R.P.M. - 13.0 Volts D.C.
5 Amp A.C. (Yellow wire)
2500 R.P.M. - 8.5 Volts A.C.
3000 R.P.M. - 11.0 Volts A.C.
3600 R.P.M. - 13.0 Volts A.C.
Models OHV 13.5 - 18.0, OV358, OV490
(3/5 Amp split)
3 Amp D.C. (Red wire)
2500 R.P.M. - 6.5 Volts D.C.
3000 R.P.M. - 9.0 Volts D.C.
3600 R.P.M. - 11.0 Volts D.C.
5 Amp A.C. (Yellow wire)
2500 R.P.M. - 15.0 Volts A.C.
3000 R.P.M. - 18.0 Volts A.C.
3600 R.P.M. - 22.0 Volts A.C.
If the above minimum values are noted, the system is
okay. Check for defective lights, wiring or switches. If
less than above values are noted, pull back the protective
shrink tubing from the diode. Using an A.C. voltmeter,
check the voltage between the alternator and diode as
shown (diag. 107). If low or no voltage is experienced,
replace the alternator.
104
5 AMP A.C.
3 AMP D.C.
RED LEAD
DIODE
BLACK LEAD
106
Yellow
Red
A.C.
DIODE
105
DIODE
Red
D.C.
Yellow
107
DIODE
A.C.
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