Kohler 14RES

TP-6735 7/17 73Section 5 Component Testing and Adjustment
5. Verify the operation of the magnetic pickup by
connecting a v oltmeter to the magnetic pickup
leads. See Figure 5-19. The voltage should be
3.0 volts AC RMS minimum during engine
cranking.
If the voltmeter displays less than 3.0 volts AC,
check the air gap as described in the following
steps before replacing the sensor. Verify that the
magnetic pickup air gap is 0.5 mm (0.020 in.).
Measure the air gap at 3 or 4 places to get an
accurate reading. See Figure 5-20.
A-358000B-C
1
2
3
4
5
1. Ignition module
2. Air gap, 0.5 mm (0.020 in.)
3. Top of flywheel ring gear tooth
4. Locknut
5. Magnetic pickup
Figure 5-20 Magnetic Pickup Air Gap
a. Use a feeler gauge to check the gap. The gap
should be 0.5 mm (0.020 in.).
b. Adjust the air gap, if necessary, by loosening
the locknut and turning the pickup. See
Figure 5-20.
c. Hold the pickup in position and retighten the
locknut.
d. Verify the magnetic pickup air gap after
tightening the locknut.
e. Reinstall the engine blower housing.
f. Reinstall the junction box and housing panels
removed to gain access to the front of the
engine.
g. After adjusting the air gap, check the voltage
again as described in step 5. If the voltage
does not measure 3.0 VAC minimum, replace
the magnetic pickup.
6. To test controller’s governing function, disconnect
the magnetic pickup leads and open the generator
set circuit breaker.
7. Manually move the throttle shaft/governor stepper
motor fully counterclockwise (closed throttle).
8. Start the generator set. The stepper motor should
step clockwise to the wide open throttle position.
The s tepper motor should remain in the clockwise
(throttle fully open) position. If the stepper motor
does not operate as described here, proceed to the
next steps to check the governor and stepper
motor.
9. Stop the generator set by pressing the OFF button
on the controller. Check the stepper motor
connections to the controller. See the wiring
diagrams in Section 7.
10. Check the stepper motor coil resistance across
pins 2 and 3 and across pins 1 and 4. Only two
stepper motor leads of each coil group are used
(BLK-YEL and RED-WHT). See Figure 5-21. The
resistance per half coil is 38.5 ohms. If one of the
coils has a significantly higher resistance or is
shorted, replace the stepper motor.
PIN 3, BLK
PIN 2, YEL
PIN 5, GRN
(not used)
PIN 4,
RED
PIN 1,
WHT
PIN 6, BLUE
(not used)
SB555
Figure 5-21 Actuator Coil Group
11. If there is power and a good ground connection to
the controller and the stepper motor coil
resistances are good, but the stepper motor does
not operate as described in step 8, the problem is
with the controller. Check controller connections,
fuses, wiring, and settings. Refer to the
troubleshooting procedures in Section 3.