12
3. Check the gap using a wire feeler gauge. Adjust
the gap by carefully bending the ground electrode.
See Figure 10. Gap CV11-15, CV460, and CV490
plugs to 1.0 mm (0.040 in.). Gap CV16 plugs to
0.76 mm (0.030 in.).
4. Reinstall the spark plug into the cylinder head.
Torque the spark plug to 38.0-43.4 N·m
(28-32 ft. lb.).
Walbro carburetors have a low idle speed screw and a
low idle fuel adjusting needle. Nikki carburetors only
have a low idle speed screw. Certified carburetors will
have fixed idle fuel or a limiter cap on the idle fuel
adjusting needle.
Figure 11. Carburetor.
The carburetor is designed to deliver the correct
fuel-to-air mixture to the engine under all operating
conditions. The main fuel jet is calibrated at the factory
and is not adjustable. The low idle fuel adjusting needle
is also set at the factory and normally does not need
adjustment.
NOTE: To ensure correct engine operation at
altitudes above 1525 meters (5000 ft.), it may
be necessary to have an authorized Kohler
dealer install a special high-altitude jet kit in
the carburetor. If a high-altitude kit has been
installed, the engine must be reconverted to
the original jet size, before it is operated at
lower altitudes, or overheating and engine
damage can result.
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.
Wire Gauge
Ground
Electrode
Spark Plug
Gap
Figure 10. Servicing Spark Plug.
Battery Charging
WARNING: Explosive Gas!
Batteries produce explosive hydrogen gas while being
charged. To prevent a fire or explosion, charge
batteries only in well ventilated areas. Keep sparks,
open flames, and other sources of ignition away from
the battery at all times. Keep batteries out of the reach
of children. Remove all jewelry when servicing
batteries.
Before disconnecting the negative (-) ground cable,
make sure all switches are OFF. If ON, a spark will
occur at the ground cable terminal which could cause
an explosion if hydrogen gas or gasoline vapors are
present.
Fuel Filter
Some engines are equipped with an in-line fuel filter.
Periodically inspect the filter and replace when dirty.
Use a genuine Kohler filter.
Carburetor Troubleshooting and
Adjustments
NOTE: Carburetor adjustments should be made
only after the engine has warmed up.
These engines are equipped with one of two basic
types of fixed main jet carburetors – Walbro or Nikki.
See Figure 11.
Walbro
Low Idle
Speed Adj.
Screw
Low Idle
Fuel Adj.
Needle
Nikki
Low Idle
Speed Adj.
Screw