Service Manual

Part Numbers
KH10091
Purpose
The stator generates 15 amps of alternating current.
How It Works
Whenever a magnet passes by a coil of wire on an iron core, electricity is
produced. The amount will depend on the thickness of the wire, the
number of windings on each coil, the strength of the magnet, and the
speed at which the magnet is moving.
This particular coil has 18 poles to produce 15 amps at 28 or more volts
A.C. when the engine is running at 3600 rpm. The current produced is
alternating current since no diode or rectifier is internal to the stator.
Note: This stator kit comes with mounting screws and terminals so that it
will retrofit to a number of different Kohler engines.
Testing
1. Remove the connector from the regulator rectifier. Measure the voltage
across the two A.C. Ieads on the alternator side of the connector with
the engine running at 3600 rpm. If voltage is less than 28 volts,
proceed to the next step. Otherwise, stator is OK.
2. With the stator still disconnected and the engine off, measure the
resistance across the two A.C. Ieads running to the stator. The
resistance should be .1 to .2 ohms. If not, replace the stator.
Part Numbers
57-9440, 92-0967
Purpose
This stator generates alternating current whenever the engine is running.
How It Works
Whenever a magnet passes by a coil of wire on an iron core, electricity is
produced. The amount will depend on the thickness of the wire, the
number of windings on each coil, the strength of the magnet, and the
speed at which the magnet is moving.
This particular coil has 18 poles to produce 20 amps at 57 volts A.C. when
the engine is running at 3600 rpm. The current produced is alternating
current since no diode or rectifier is internal to the stator.
Testing
1. Disconnect the alternator from the regulator/rectifier.
2. Measure the voltage across the A.C. terminals on the alternator side of
the connector. The voltage should read as shown in Figure A.
3. Check for a short in the alternator by checking between either of the
A.C. terminals and ground. If you do not get infinite resistance, replace
the alternator.
4. Check for an open alternator circuit by checking the resistance between
the two A.C. Ieads coming from the alternator. You should find the
resistance as called out in Figure A. If you have not found the problem,
test the regulator/rectifier, check for poor connections, and test the
rotor for poor magnetism.
Alternator
15 Amp
(Kohler)
Alternator
20 Amp
(with terminals)
(Onan)
Stator Output* Stator Resistance
more than 28
VDC @ 3600 rpm
.1 - .2 Ohms
*With regulator/rectifier disconnected
Item Specification
Battery 12-13 VDC
Stator Voltage Approximately 29 VDC
@ 1800 RPM.
Approximately 57 VDC
@ 3600 RPM.
Stator
Resistance
0.10 + 0.19 Ohms
Figure A
Glossary
GLOSSARY
Demystification Guide 3-5