Kohler COMMAND CH18, Service Manual

Page: 41 / 232

5.8
Section 5
Fuel System and Governor
Models with Governed Idle System
An optional governed idle control system is supplied
on some engines. The purpose of this system is to
maintain a desired idle speed regardless of ambient
conditions (temperature, parasitic load, etc.) that may
change. Engines with this feature contain a small
secondary spring connected between the governor
lever and the lower adjustment tab of the main
bracket. See Figure 5-7.
The system requires an additional procedure for
setting the idle speed. If speed adjustments are
required proceed as follows.
1. Make any necessary speed or control
adjustments following the appropriate
instructions covered in this section.
2. Move the throttle control to the idle position.
Hold the governor lever away from the
carburetor, or hold the throttle lever so it is tight
against the idle speed adjusting screw, to negate
the governor activation. See Figure 5-8. Check
the speed with a tachometer and adjust it to 1500
RPM.
3. Release the governor lever and allow the engine
to return to the governed idle speed. Check it
with a tachometer against the equipment
manufacturers recommended idle speed.
Governed Idle Speed (RPM) is typically 300 RPM
(approximate) higher than the low idle speed. If
adjustment is necessary, bend the adjusting tab
on the speed control assembly to set. See Figure
5-7.
Figure 5-7. Governed Idle Spring Location.
Governed
Idle Spring
Tab
Hold Throttle
Lever Against
Screw
Servicing
Figure 5-9. Carburetor Detail.
Screws
Fuel Line
Figure 5-8. Holding Throttle Lever Against Idle
Stop Screw (One-Barrel Carburetor).
Float
It is not necessary to remove the carburetor from the
engine to check and adjust the float.
1. Remove the air cleaner and breather hose. Refer
to Section 9 – ‘‘Disassembly”.
2. Disconnect the fuel line from the carburetor. See
Figure 5-9.
3. Clean dirt and debris from exterior of carburetor.
4. Remove the four screws holding the two
carburetor halves together. Carefully lift the
upper body off the carburetor body and
disconnect choke linkage.
5. Hold the carburetor upper body so that the float
assembly hangs vertically and rests lightly
against the fuel inlet needle. The fuel inlet needle
should be fully seated, but the needle tip should
not be depressed. See Figure 5-10.