Digital Spark Advance Module (Dsam); Fuel Metering Valve Adjustment - Kohler 8.5RES Service Manual

5.10.5 Digital Spark Advance Module
(DSAM)
The digital spark advance module (DSAM) on the Model
12RES optimizes the engine timing for the selected fuel,
natural gas or LP. The location of the DSAM is shown in
Figure 5-22. Connect the DSAM leads in the air intake
compartment together for natural gas fuel. Disconnect
the leads if LP is used. See Figure 5-23.
See the engine Service Manual for DSAM service
information.
1. DSAM leads: connect for natural gas, disconnect for LP.
Figure 5-23 Digital Spark Advance Module (DSAM)
Leads (located in generator set air intake
area)

5.10.6 Fuel Metering Valve Adjustment

The fuel system is factory-adjusted to comply with
applicable emission standards and to provide the best
possible hot and cold starting.
Note: Adjusting the
emissions-certified generator sets may void the
emission certification.
Use a universal exhaust gas oxygen (UEGO) sensor to
check the fuel mixture after replacing the fuel regulator,
carburetor, or silencer. Use the following procedure to
check the fuel mixture after the engine has reached
normal operating temperature.
readings must fall within the range shown in
Figure 5-26.
The fuel metering valves are sealed to prevent field
adjustments. If the fuel metering valve requires
adjustment, do not break the seals on the fuel
adjustment block. Obtain a new fuel adjustment block
from the manufacturer and replace the sealed block with
TP-6196 5/04
1
fuel metering valves
The UEGO sensor
the new part. Refer to the generator set Parts Catalog
for the fuel block part number.
Only trained, authorized service technicians may adjust
the fuel metering valves. The adjustment procedure
requires a digital volt meter (DVM), UEGO oxygen
sensor service kit GM29385, and a load bank capable of
the rated kW for the fuel being used. Always use an
oxygen sensor when adjusting the fuel metering valves.
Observe the following safety precautions while
performing the procedure.
Hot engine and exhaust system.
Can cause severe injury or death.
Do not work on the generator set until
it cools.
Servicing the exhaust system.
severe injury or death. Do not touch hot engine parts. The
engine and exhaust system components become extremely
hot during operation.
tp6195
Fuel Mixture Check/Fuel Metering Valve
Adjustment Procedure
1. Place the generator set master switch in the OFF
position.
2. Disconnect power to the battery charger.
3. Remove the oxygen sensor plug from the exhaust
manifold. See Figure 5-25 for location.
4. Install the oxygen sensor in the exhaust manifold
where the plug was removed. Connect the snesor
to the engine starting battery, control module, and
on
voltmeter as shown in Figure 5-24.
5. Reconnect power to the battery charger.
6. Place the controller master switch in the RUN
position to start the generator set.
7. Allow the generator set to run until the engine
reaches normal operating temperature.
8. With the generator set at normal operating
temperature, apply rated load.
9. Connect one of the DVM leads to the oxygen
sensor lead.
ground and measure the output voltage of the
oxygen sensor (potential to ground).
Section 5 Component Testing and Adjustment
WARNING
Hot parts can cause
Connect the other DVM lead to
57