16
Carburetor Troubleshooting and
Adjustments
In compliance with the government emission
standards, the carburetor is calibrated to deliver the
correct fuel-to-air mixture to the engine under all
operating conditions. The carburetor cannot be
adjusted, except for low idle speed (RPM). Carburetor
servicing is to be performed by an authorized Kohler
Engine Service Dealer only. See Figure 24.
• Make sure fuel is reaching the carburetor. This
includes checking the fuel lines and fuel pump for
restrictions or faulty components, replace as
necessary.
• Make sure the air cleaner element and precleaner
are clean and properly secured.
• Make sure the air intake screen, blower housing,
and cooling surfaces of radiator are clean and free
of dirt and debris.
• Make sure cooling system is filled to the proper
level.
If, after checking the items listed above, the engine is
hard to start, runs roughly, or stalls at low idle speed, it
may be necessary to adjust or service the carburetor.
Adjust Carburetor
Start the engine and run at half throttle for 5 to 10
minutes to warm up. The engine must be warm before
making final settings.
Low idle speed (RPM) setting:
1. Place the throttle control into the “idle” or “slow”
position. Set the low idle speed to 1200 RPM*
(± 75 RPM) by turning the low idle speed adjusting
screw in or out. Check the speed using a
tachometer.
*NOTE: The actual low idle speed depends on the
application – refer to equipment
manufacturers recommendations. The
standard low idle speed is 1200 RPM.
2. If proper operation is not restored after adjusting
the low idle speed, carburetor servicing by an
authorized Kohler Engine Service Dealer may be
required.
Figure 24. Carburetor.
Troubleshooting
If engine troubles are experienced that appear to be
fuel system related, check the following areas before
adjusting the carburetor.
• Make sure the fuel tank is filled with clean, fresh
gasoline.
• Make sure the fuel tank cap vent is not blocked
and that it is operating properly.
• If the fuel tank is equipped with a shut-off valve,
make sure it is open.
• If the engine is equipped with an in-line fuel filter,
make sure it is clean. Replace the filter if it is dirty
or restricted.
Fuel Line
Inlet
Idle Speed
Adjusting Screw
Fuel Shut-Off
Solenoid
