Battery Charging; Lpg Regulator; Fuel Filter - Kohler CH640 Owner's Manual

NOTE: Do not clean the spark plugs in a machine
using abrasive grit. Some grit could remain in
the spark plug and enter the engine causing
extensive wear and damage.
3. Check the gap using a wire feeler gauge. Adjust
the gap according to the chart by carefully
bending the ground electrode. See Figure 10.
Wire Gauge
Spark Plug
Ground
Electrode
Figure 10. Servicing Spark Plug.
4. Reinstall the spark plug into the cylinder
head. Torque the spark plug to 24.4-29.8 N·m
(18-22 ft . lb.).

Battery Charging

WARNING: Explosive Gas!
Batt eries produce explosive hydrogen gas while being
charged. To prevent a fi re or explosion, charge batt eries only
in well ventilated areas. Keep sparks, open fl ames, and other
sources of ignition away from the batt ery at all times. Keep
batt eries out of the reach of children. Remove all jewelry
when servicing batt eries.
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 LPG/NG fuel vapors are present.
Charging of batt ery should be performed as outlined
by the original equipment manufacturer (OEM) in
their operator's manual.

Fuel Filter

The fi lter of the LPG/NG fuel system is an integral
part within the lock-off /fi lter assembly. All service
relating to the lock-off /fi lter is to be performed by an
authorized Kohler Engine Service Dealer or qualifi ed
LPG personnel only. Servicing of fi lter is recommended
every 500 hours.
12
Fuel Line
These engines use low permeation rated fuel lines,
certifi ed to comply with California and U.S. EPA
evaporative emission requirements. Fuel lines that do
not meet these requirements may not be used. Order
replacement hose through a Kohler Service Center.
Carburetor Troubleshooting and
Adjustments
In compliance with government emission standards,
the carburetor and the regulator are calibrated and
preset to deliver the correct fuel-to-air mixture to the
engine under all operating conditions and cannot
be adjusted, except for low idle speed. Carburetor
servicing is to be performed by an authorized Kohler
Engine Service Dealer only. See Figure 11.
Gap
Figure 11.

LPG Regulator

In compliance with government emission standards,
the regulator is preset at the factory to provide the
proper supply of fuel. No adjustment or resett ing
of regulator is to be made. All service relating to the
regulator must be performed by an authorized Kohler
Engine Service Dealer or qualifi ed LPG personnel
only.
Over time, fuel deposits can accumulate inside the
regulator. Removing these deposits is recommended
(Nikki regulators only) every 500 operating hours, or
annually, whichever comes fi rst.
Nikki Regulators
Every 500 hours/annually drain regulator:
1. Turn fuel supply valve off , run engine out of fuel,
and turn off ignition switch.
2. Disconnect and ground the spark plug leads.
3. Remove the 1/8" pipe plug from the bott om of
regulator. Remove any accumulated deposits. See
Figure 12.
Low Idle
Speed
Adjusting
Screw