Service Manual

32
Electrical System
KohlerEngines.com 66 690 01 Rev. C
Test for Spark
NOTE: If 2 testers are available, testing can be performed simultaneously for both cylinders. However, if only 1 tester
is available, 2 individual tests must be performed. Side not being tested must have spark plug lead connected
or grounded. Do not crank engine or perform tests with 1 spark plug lead disconnected and not grounded, or
permanent system damage may occur.
1. With engine stopped, disconnect 1 spark plug lead. Connect spark plug lead to post terminal of spark tester and
attach tester clip to a good engine ground.
2. Crank engine over, establishing a minimum of 550-600 RPM, and observe tester(s) for spark.
3. Repeat spark test on opposite cylinder if cylinders are being tested individually.
Condition Possible Cause Conclusion
Both cylinders have good spark but
engine runs poorly or existing plug
condition is questionable.
Spark Plug(s) Install new spark plug(s) and retest
engine performance.
1 cylinder has good spark and other
cylinder has no or intermittent spark.
Ignition Test ignition modules and
connections.
No spark at either cylinder. Ignition Switch Recheck position of ignition switch
and shorted kill lead.
BATTERY CHARGING SYSTEM
NOTE: Observe following guidelines to avoid damage to electrical system and components:
● Make sure battery polarity is correct. A negative (-) ground system is used.
● Disconnect rectifi er-regulator plug and/or wiring harness plug before doing any electric welding on equipment
powered by engine. Disconnect all other electrical accessories in common ground with engine.
● Prevent stator (AC) leads from touching or shorting while engine is running. This could damage stator.
NOTE: 20 amp charging systems use a 15 amp stator with a 25 amp rectifi er-regulator.
Most engines are equipped with a 15, 20, or 25 amp regulated charging system.
15/20/25 Amp Regulated Charging System
Stator
Stator is mounted on crankcase behind fl ywheel. Follow
procedures in Disassembly and Reassembly if stator
replacement is necessary.
Rectifi er-Regulator
NOTE: When installing rectifi er-regulator, take note of
terminal positions and install plug correctly.
NOTE: Disconnect all electrical connections attached to
rectifi er-regulator. Testing may be performed
with rectifi er-regulator mounted or loose. Repeat
applicable test procedure 2 or 3 times to
determine condition of part.
Rectifi er-regulator is mounted on backing shroud
assembly. To replace it, disconnect plug, remove
mounting screws, and ground lead.
Testing rectifi er-regulator may be performed as follows,
using appropriate rectifi er-regulator tester.
To test 20/25 amp rectifi er-regulators:
1. Connect single lead adapter in between B+ (center)
terminal of rectifi er-regulator being tested and
squared single end of tandem adapter lead.
2. Connect tester ground lead (with spring clamp) to
body of rectifi er-regulator.
3. Connect red lead and 1 black lead to terminals on
open end of tandem adapter lead (connections are
not location specifi c).
4. Connect remaining black lead from tester to 1 outer
AC terminal on rectifi er-regulator.
5. Plug tester into proper AC outlet/power for tester
being used. Turn on power switch. POWER light
should be illuminated and 1 of 4 status lights may be
on as well. This does not represent condition of part.
6. Press TEST button until a click is heard and then
release. Momentarily 1 of 4 lights will illuminate
indicating partial condition of part.
To test 15 amp rectifi er-regulators:
1. Connect tester ground lead (with spring clamp) to
body of rectifi er-regulator being tested.
2. Connect tester red lead to B+ terminal of rectifi er-
regulator and 2 black tester leads to 2 AC terminals.
3. Plug tester into proper AC outlet/power for tester
being used. Turn on power switch. POWER light
should be illuminated and 1 of 4 status lights may be
on as well. This does not represent condition of part.
4. Press TEST button until a click is heard and then
release. Momentarily 1 of 4 status lights will
illuminate indicating condition of part.