Kohler KG2204T Instruction Manual

Operation
Engine
Engine Models:
KG2204 Naturally Aspirated
KG2204T Turbocharged
Liquefied Petroleum Gas (LPG)/Propane/
Natural Gas (NG) Fueled
TP-6901 3/16a

INTRODUCTION
This manual provides operating and maintenance instructions for KOHLER Engine Models KG2204 and
KG2204T. Keep this manual with the equipment for future reference. Refer to the KG2204 and KG2204T
Service Manual for detailed information on adjusting and servicing the engine.
Information in this publication represents data available at the time of print. KOHLER Co. reserves the right
to change this publication and the products represented without notice and without any obligation or
liability whatsoever.
This engine operates on either Propane, Liquefied Petroleum Gas (LPG) or Natural Gas (NG), which are
extremely flammable and explosive. Installation and repair of LPG/NG systems must be performed only by
qualified LPG/NG technicians. Read this manual and carefully follow all procedures and safety precautions
to ensure proper equipment operation and to avoid bodily injury.
Regular maintenance is necessary for safe and efficient operation. Inspect the engine often and perform
required maintenance at prescribed intervals. Service work must be performed by appropriately skilled and
suitably trained maintenance personnel who are familiar with engine diagnostics and repair.
Unless otherwise specified, all units of measurement are metric, followed by the Imperial (U.S.) equivalent.
California Proposition 65
WARNING
!
Engine exhaust from this product contains chemicals
known to the State of California to cause cancer,
birth defects, or other reproductive harm.

3
Section 1 Engine Identification and Technical Support
1.1 Know Your Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Purchase Date . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.2 Related Literature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.3 Service Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Section 2 Safety Precautions
2.1 Safety Alerts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
2.2 Safety Information For This Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Section 3 Components and Maintenance Locations
3.1 Model KG2204 Engine Side Views . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.2 Model KG2204 Front and Rear Views . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.3 Model KG2204T Engine Side Views . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.4 Model KG2204T Front and Rear Views . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Section 4 Operation
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.2 Fuel System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Fuel Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
NG to LPG Conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.3 Before Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.4 Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
4.5 Cold Weather Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.6 Monitoring Engine Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
4.7 Stopping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Section 5 Maintenance
5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
5.2 Fluid Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Oil Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Grease Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Coolant Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
5.3 Periodic Maintenance Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
5.4 Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Check Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Change Engine Oil and Oil Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Check and Clean the Air Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Replace the Air Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Check and Adjust the Spark Plugs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Replace the Spark Plugs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Ignition Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

4
5.5 Electrical System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Check Battery and Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Check and Adjust the Drive Belt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Replace the Drive Belt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Check Wiring and Electrical Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
5.6 Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Check Coolant Level and Condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Check Hoses and Clamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
5.7 Fuel System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Check Fuel Supply Pipe and Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Check Fuel Level (LPG only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Section 6 Troubleshooting
6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
6.2 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Section 7 Storage
7.1 Preparation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
7.2 Short-Term Storage (Less than 30 days) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
7.3 Long-Term Storage (More than 30 days) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
7.4 Maintenance While In Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
7.5 Removal From Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Section 8 Specifications
8.1 Engine Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
8.2 Specifications of Main Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
8.3 Adjustment Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
8.4 Torque Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
8.5 Standard Torque Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

ENGINE IDENTIFICATION AND TECHNICAL SUPPORT
TP-6901 3/16a Engine Identification and Technical Support 5
Section 1 Engine Identification and
Technical Support
1.1 KNOW YOUR ENGINE
Product identification numbers determine service parts.
Record the product identification numbers in the
spaces below immediately after unpacking the
products so that the numbers are readily available for
future reference.
Engine Identification
Record the product identification information from the
engine nameplate.
Model Designation: __________________________
Serial Number: __________________________
Purchase Date
Upon purchase of your KOHLER equipment, record
the purchase date for reference when communicating
with your authorized KOHLER distributor/dealer.
1.2 RELATED LITERATURE
Related Literature identifies related literature available
for the KG2204 and KG2204T engines. Only trained
and qualified personnel should install or service this
engine.
1.3 SERVICE PARTS
Contact a KOHLER authorized distributor/dealer for all
maintenance, service, and engine parts. To find a
KOHLER authorized distributor/dealer, visit
KOHLERPower.com or call 1-800-544-2444 (U.S. and
Canada).
Literature Type Part Number
KOHLER Models KG2204 and
KG2204T
Service Manual
TP-6902
KOHLER Models KG2204 and
KG2204T
Service Manual / Troubleshooting /
Diagnostics
TP-6903
KOHLER Models KG2204 and
KG2204T
Service Parts Manual
TP-6904

ENGINE IDENTIFICATION AND TECHNICAL SUPPORT
6 Engine Identification and Technical Support TP-6901 3/16a

SAFETY PRECAUTIONS
TP-6901 3/16a Safety Precautions 7
Section 2 Safety Precautions
2.1 SAFETY ALERTS
NOTE:
A Note is used to inform you of
important installation, operation, or
maintenance information.
2.2 SAFETY INFORMATION FOR THIS ENGINE
!
DANGER
Danger indicates the presence
of a hazard that will cause
severe personal injury, death, or
substantial property damage.
NOTICE
Notice communicates
installation, operation, or
maintenance information that is
safety related but not hazard
related.
WARNING
!
Warning indicates the presence
of a hazard that can cause
severe personal injury, death, or
substantial property damage.
!
CAUTION
Caution indicates the presence
of a hazard that will or can cause
minor personal injury or
property damage.
WARNING
!
Carbon
monoxide can
cause severe
nausea, fainting,
or death.
Avoid inhaling
exhaust fumes.
Engine exhaust gases contain
poisonous carbon monoxide.
Carbon monoxide is odorless,
colorless, and can cause death if
inhaled.
WARNING
!
Risk of Fire. Can cause severe
injury or death.
Do not smoke or permit flames or
sparks near fuels or the fuel
system.
!
CAUTION
Electrical shock
can cause injury.
Do not touch
wires while
engine is running.
WARNING
!
Rotating parts
can cause
severe injury.
Stay away while
the engine is in
operation.
Keep hands, feet, hair, and clothing
away from all moving parts to
prevent injury. Never operate the
engine with covers, shrouds, or
guards removed.
WARNING
!
Hot parts can
cause severe
burns.
Do not touch
engine while
operating or just
after stopping.
Never operate engine with heat
shields or guards removed.

SAFETY PRECAUTIONS
8 Safety Precautions TP-6901 3/16a
WARNING
!
Hot liquid can
cause severe
burns.
Do not loosen
radiator cap while
engine is
operating or warm
to touch.
Liquid coolant can be extremely hot
from operation. Turning radiator
cap when engine is hot can allow
steam and scalding liquid to blow
out and burn you severely. Shut off
machine. Only remove radiator cap
when cool enough to touch with
bare hands. Slowly loosen cap to
the first stop to relieve pressure
before removing completely.
WARNING
!
Accidental starts
can cause
severe injury or
death.
Disconnect and
ground spark plug
leads before
servicing.
Before working on engine or
equipment, disable engine as
follows: 1) Disconnect spark plug
leads. 2) Disconnect negative (–)
battery cable from battery.
Before disconnecting 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.
WARNING
!
Explosive fuel
can cause fires
and severe
burns.
If a gaseous odor
is detected,
ventilate the area
and contact an
authorized service
technician.
LPG (Liquefied Petroleum Gas) is
extremely flammable and tends to
settle in low areas where a spark or
flame could ignite the gas. Do not
start or operate this engine in a
poorly ventilated area where
leaking gas could accumulate and
endanger the safety of persons in
the area.
NG (Natural Gas) is extremely
flammable, is lighter than air, and
rises. Do not start or operate this
engine in a poorly ventilated are
where leaking gas could
accumulate and endanger the
safety of persons in the area.
To ensure personal safety,
installation and repair of LPG/NG
fuel supply systems must be
performed only by qualified
LPG/NG system technicians.
Improperly installed and
maintained LPG/NG equipment
could cause the fuel supply system
or other components to
malfunction, causing gas leaks.
Observe federal, state, and local
laws governing LPG/NG fuel,
storage, and systems.
WARNING
!
Handling caustic
engine fluids
and chemical
products can
cause severe
chemical burns,
nausea, fainting,
or death.
Most chemicals such as used
engine oil, antifreeze/coolant, rust
proofing agent, inhibiting oil,
degreasing agent, spray paint, and
adhesives are hazardous to health.
Read and follow the user
information found on the
packaging. Avoid inhalation and
skin contact. Use only in
well-ventilated areas and use a
protective mask when spraying.
Store engine fluids and chemical
products in a locked cabinet.
Contact your local recycling center
for disposal information and
locations.
Fire-damaged or burned O-rings
may cause the formation of
hydrofluoric acid. Contact with
hydrofluoric acid may cause severe
skin irritation and chemical burns.
O-rings and other fluoroelastomer
seals exposed to fire or
temperatures above 316°C (600°F)
(i.e., during welding) may
decompose forming hydrofluoric
acid. Avoid inhalation or skin
contact. Do not incinerate O-rings.
Dispose of O-ring waste material in
a responsible manner.

SAFETY PRECAUTIONS
TP-6901 3/16a Safety Precautions 9
WARNING
!
Explosive fuel
vapors. Can
cause severe
injury or death.
Use extreme care
when handling,
storing, and using
fuels.
Gas fuel leaks. Explosive fuel
vapors can cause severe injury or
death. Fuel leakage can cause an
explosion. Check the LPG vapor or
natural gas fuel system for leakage
by using a soap and water solution
with the fuel system test
pressurized to 6–8 ounces per
square inch (10–14 inches water
column). Do not use a soap
solution containing either ammonia
or chlorine because both prevent
bubble formation. A successful test
depends on the ability of the
solution to bubble.
Used engine oil. Contact with used
engine oil may cause severe skin
irritation. Repeated and prolonged
skin exposure may have other
health risks. Used engine oil is a
suspected carcinogen. Avoid
contact with skin. Thoroughly wash
your hands and nails with soap and
water shortly after handling used
engine oil. Wash or dispose of
clothing or rags containing used
engine oil. Dispose of used engine
oil in a responsible manner.
Contact your local recycling center
for disposal information and
locations.

SAFETY PRECAUTIONS
10 Safety Precautions TP-6901 3/16a

COMPONENTS AND MAINTENANCE LOCATIONS
TP-6901 3/16a Components and Maintenance Locations 11
Section 3 Components and Maintenance
Locations
3.1 MODEL KG2204 ENGINE SIDE VIEWS
Figure 3-1
1 Rocker Arm Cover 7 Air-Fuel Mixer 13 Oil Pan 19
Knock Sensor (if
equipped with
turbocharger)
2 Rear Hanger 8 Throttle Body 14 Battery Charging
Alternator 20
Oil Cooler Adapter
(not included on
all models)
3Crankcase
Breather 9 TMAP Sensor1
1) Air Temperature / Manifold Absolute Pressure (TMAP)
15 Oil Pump Drive 21 Oil Pan Drain Plug
4 Spark Plug Wires 10 Intake Manifold 16 Ignition Coil 22 Oil Pressure
Sender
5 Oil Filler Cap 11 Flywheel 17 Crankshaft
Position Sensor 23 Oil Filter Base
6 Front Hanger 12 Exhaust Manifold 18 Oil Dipstick and
Tube 24 Oil Filter
2
34
5
7
1
89
1213
10
14
6
21
17
16
18
19
23
24
22
11
15
20
K0695 K0403

COMPONENTS AND MAINTENANCE LOCATIONS
12 Components and Maintenance Locations TP-6901 3/16a
3.2 MODEL KG2204 FRONT AND REAR VIEWS
Figure 3-2
1 Air-Fuel Mixer 8 Ignition Coil 15 Crankshaft
Position Sensor 22 Flywheel
2 Throttle Body 9 Oil Dipstick 16 Timing Cover 23 Exhaust Manifold
Studs
3 TMAP Sensor 10 Fuel Control Valve 17 Oil Drain Plug 24 Oil Pan
4Upper Intake
Manifold 11 Upper Coolant Outlet 18 Oil Pressure Sensor (PGS) 25 Exhaust Manifold
5 PCV Valve 12
Coolant
Temperature
Sensor
19 Oil Filter Base 26 Battery Charging
Alternator
6 Rocker Arm Cover 13 Drive Belt 20
Oil Cooler Adapter
(not included on
all models)
27 Water Pump Inlet
7 Oil Filter 14 Vibration
Dampener 21 Lower Intake Manifold
2
34
5
7
1
8
9
14
15
10
17
6
21
22
11
1
12
13
19
16
23
24
26
K0693K0647
27
18
20
25

COMPONENTS AND MAINTENANCE LOCATIONS
TP-6901 3/16a Components and Maintenance Locations 13
3.3 MODEL KG2204T ENGINE SIDE VIEWS
Figure 3-3
1 Regulator to FCV Hose 9 Throttle Body 16 Oil Pump Drive
2 FCV to Mixer Hose 10 TMAP Sensor1
1) Air Temperature / Manifold Absolute Pressure (TMAP)
17 Crankshaft Position Sensor
3 Fuel Control Valve (FCV) 11 Intake Manifold 18 Ignition Coil
4 Rear Hanger 12 Flywheel 19 Oil Dipstick and Tube
5 Oil Filter 13 Turbocharger 20 Oil Cooler Adapter and
Stand-off
6 Spark Plug Wires 14 Oil Pan 21 Engine Control Module
7 Oil Filler Cap 15 Battery Charging Alternator 22 Turbo Oil Feed Line
8 Front Hanger
2
4
1
611
idGM88249
12
13
14
15
16
17
18
19
20
21
22
3
78910
5

COMPONENTS AND MAINTENANCE LOCATIONS
14 Components and Maintenance Locations TP-6901 3/16a
3.4 MODEL KG2204T FRONT AND REAR VIEWS
Figure 3-4
1 Throttle Body 9 Coolant Temperature
Sensor 17 Crankshaft Position Sensor
2 Upper Intake Manifold 10 Lower Intake Manifold 18 Timing Cover
3 Fuel Control Valve 11 Turbo Oil Feed Line 19 Oil Pressure Sensor
4 Oil Filter 12 Turbocharger 20 Flywheel
5 Coil 13 Drive Belt 21 Dual Fuel Regulator (DFR)
6 Spark Plug Wires 14 Turbo Oil Return Line 22 Air-Fuel Mixer
7 Oil Dipstick 15 Vibration Dampener 23 DFR Breather Hose
8 Upper Coolant Outlet 16 Oil Pan
idGM88249
2
4
1
6
11
12
13
14
15
16
17
18
19
20
21
23
3
5
789
10
22

OPERATION
TP-6901 3/16a Operation 15
Section 4 Operation
4.1 INTRODUCTION
The KG2204 and KG2204T are four-stroke internal
combustion engines certified to operate on either
Propane, Liquid Petroleum Gas (LPG) or Natural Gas
(NG). System configuration is factory preset for NG.
Instructions for switching to LPG are provided within
this section.
The fuel system on this engine is a closed loop design.
As the engine runs, sensors located at various points
within the system provide continuous operating
feedback to the Engine Control Module (ECM). The
ECM adjusts the engine speed, ignition timing, and fuel
supply in response to changes in the applied load,
surrounding air temperature, operating temperature of
the engine, and amount of oxygen present in the
exhaust.
Refer to the equipment Operation Manual for specific
information on how fault codes are displayed.
4.2 FUEL SYSTEM
Components
Fuel Shut-Off Valves
Figure4-1
The fuel supply contains two fuel shut-off valves
located upstream from the fuel connection point on the
engine. Each valve consists of a 12V solenoid and a
normally closed port. When energized, the solenoid
opens the valve and allows the LPG/NG vapor to flow
through the system.
The valves are open during the engine cranking and
run cycles. Voltage to the valves is controlled by the
ECM.
K0404

OPERATION
16 Operation TP-6901 3/16a
Fuel Pressure Regulator
Figure4-2
The fuel pressure regulator modulates the pressure of
the LPG/NG vapor to the air-fuel mixer.
The fuel pressure regulator is not adjustable. However,
a selector at the base of the regulator is rotated when
switching from NG to LPG and back. See “NG to LPG
Conversion” on page 20 for instructions.
Fuel Control Valve
z
Figure4-3
The fuel control valve is an ECM-controlled vacuum
switch that adjusts the fuel pressure delivered from the
fuel pressure regulator to the air-fuel mixer.
Air-Fuel Mixer
Figure4-4
The air-fuel mixer is mounted in the air stream ahead of
the throttle. It is a nonadjustable metering device that
combines LPG/NG vapor with intake air for
combustion.
fThrottle Body
K0692
K0379
NOTICE
Avoid the possibility of component damage. The
air-fuel mixer is an emission control device.
Components inside the mixer are specifically
calibrated to meet the engine’s emission
requirements and should never be disassembled
or rebuilt. If the mixer fails to function correctly,
contact your KOHLER authorized distributor or
dealer.
K0380

OPERATION
TP-6901 3/16a Operation 17
Throttle Body
Figure4-5
Figure4-6
The throttle body controls the operating speed of the
engine according to input from the ECM. Defaults
programmed into the ECM software, along with throttle
position sensors, allow the ECM to control the overall
operation of the engine in response to changing
speeds and loads.
Turbocharger
Figure4-7
The Model KG2204T engine is equipped with a
turbocharger. The turbocharger utilizes exhaust gas
flowing through the turbine to spin a compressor. The
turbocharger compressor increases boost pressure
and density of the air/fuel mixture entering the intake
manifold resulting in higher power output compared to
the naturally aspirated engine. A wastegate on the
turbocharger bypasses exhaust gas around the turbine
when the boost pressure reaches a maximum limit.
Turbocharger Oil Lines
The Model KG2204T engine is equipped with a
turbocharger. The turbocharger bearings require oil for
lubrication and cooling. Oil is fed to the turbocharger
bearings from the oil supply line on the top side of the
bearing housing and returned to the oil sump through a
line connecting the bottom side of the bearings to the
sump.
Charge Air Cooler
Figure4-8
The Model KG2204T engine is equipped with a charge
air cooler. The charge air cooler (A) cools the
compressed air/fuel mixture before it enters the intake
manifold. The cooler intake manifold charge helps
maintain emissions at the high power level of the
turbocharged engine.
K0679
idGM91526
idGM92075
A

OPERATION
18 Operation TP-6901 3/16a
Engine Control Module (ECM)
Figure4-9
The ECM is a digital controller that oversees the
various operating parameters of the engine. The ECM
receives input data from sensors mounted to the
engine and fuel system, and then outputs various
signals to adjust engine operation.
The ECM also performs diagnostic functions on the
fuel system. If a malfunction occurs, the ECM sends a
fault signal to alert the operator to the problem. A
corresponding Diagnostic Trouble Code (DTC) is
generated and stored in memory within the ECM. A
technician can then use a computerized diagnostic
scan tool to retrieve the stored DTC number(s) and
identify the problem.
Sensors
Heated Exhaust Gas Oxygen (HEGO) Sensor
The Heated Exhaust Gas Oxygen (HEGO) sensor
measures the amount of oxygen present in the exhaust
stream to determine whether the air-fuel ratio is too rich
or too lean.
Air Temperature / Manifold Absolute Pressure
(TMAP) Sensor
The Air Temperature / Manifold Absolute Pressure
(TMAP) sensor monitors the absolute pressure in the
intake manifold. This sensor also measures the
temperature of the incoming air. Data returned by the
TMAP sensor prompts the ECM to adjust the air-fuel
mixture as needed.
Crankshaft Position Sensor
Crankshaft Position Sensor (CPS) measures the rotary
speed and crankshaft turning angle. The ECM ensures
the ignition timing for each cylinder depending on the
turning signal. The sensor, which consists of a
permanent magnet and coil, is installed on the timing
gear cover next to the crankshaft pulley. When the
crankshaft is turning, the gear ring passes the sensor
at different speeds and causes a change of magnet
resistance at the sensor to produce a changeable
signal.
Throttle Position Sensor (TPS)
The electronic throttle control device incorporates an
internal Throttle Position Sensor (TPS), which provides
output signals to the ECM as to the location of the
throttle shaft and blade. The ECM will use the signal to
monitor and adjust the engine speed.
Engine Coolant Temperature Sensor
The engine coolant temperature sensor provides
engine coolant temperature data to the ECM. The ECM
uses this data to adjust for cold starting conditions, and
regulates various fuel and emission control functions.
Engine Oil Pressure Sender
The engine oil pressure sender ensures sufficient
lubrication throughout the engine. The sender is a
pressure valve that is monitored by the ECM. A drop in
pressure will trigger a fault code.
Figure4-10
Up-Stream Throttle Manifold Air Pressure (MAP)
Sensor (KG2204T)
The Up-stream Thr ottle Manifold Air Pressure sensor
monitors the absolute pressure in the air induction
system up-stream of the throttle. Data returned by the
MAP sensor prompts the ECM to adjust the air-fuel
mixture as needed.
idGM88425
idGM92075

OPERATION
TP-6901 3/16a Operation 19
Fuel Specifications
NOTICE
Natural gas and propane installations must be
installed in accordance with applicable federal,
state, and local law, and with the National Fire
Protection Association (NFPA) Pamphlet #58,
standard for storage and handling of Liquefied
Petroleum Gases, to the extent that these
standards are not in violation of federal, state, or
local law.
Table 4-1: Fuel Specifications
Fuel Type Item
Specification
KG2204 KG2204T
Liquid Propane
Gas (LPG)
Type HD-5 or HD-10
Maximum fuel pressure
(engine OFF, no load) 11.0" W.C.
Minimum fuel pressure
(engine ON, full load) 5.0" W.C.
Natural Gas (NG) Supply Standard pipeline
Approximate supply volume 37.257 kJ/m3 (1000 BTU/ft.3)
Minimum flow 11.9 m3/hr. (420 SCFH)
@ 5.0" W.C.
19.6 m3/hr. (690 SCFH)
@ 5.0" W.C.
Allowable water vapor Less than 112.3 kg per 1 million m3
(Less than 7 lb. per 1 million ft.3)
Maximum fuel pressure
(engine OFF, no load) 11.0" W.C.
Minimum fuel pressure
(engine ON, full load) 5.0" W.C.
LPG and NG
(both)
Fuel handling and supply
component constraints
UL 2200: Standard for Stationary Engine Equipment
Assemblies
Operating temperature range –20°C (–4°F) to 105°C (221°F)

OPERATION
20 Operation TP-6901 3/16a
NG to LPG Conversion
The KG2204 and KG2204T engines are easily
configurable for use with either NG or LPG. System
configuration for NG or LPG requires a mechanical
setting on the fuel pressure regulator and an electrical
setting change at the ECM. These adjustments will
ensure that the proper fuel and spark timing is supplied
to the engine.
NOTE:
The fuel pressure regulator is factory preset for NG.
When using NG, no mechanical adjustment is required.
Figure4-11
WARNING
!
Accidental starts can cause
severe injury or death.
Disconnect and ground spark
plug leads before servicing.
Before working on engine or equipment, disable
engine as follows: 1) Disconnect spark plug leads.
2) Disconnect negative (–) battery cable from battery.
Before disconnecting 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.
WARNING
!
Risk of Fire. Can cause severe injury or death.
Do not smoke or permit flames or sparks near fuels or
the fuel system.
WARNING
!
Explosive fuel can cause fires and
severe burns.
If a gaseous odor is detected,
ventilate the area and contact an
authorized service technician.
LPG (Liquefied Petroleum Gas) is extremely
flammable and tends to settle in low areas where a
spark or flame could ignite the gas. Do not start or
operate this engine in a poorly ventilated area where
leaking gas could accumulate and endanger the
safety of persons in the area.
NG (Natural Gas) is extremely flammable, is lighter
than air, and rises. Do not start or operate this engine
in a poorly ventilated are where leaking gas could
accumulate and endanger the safety of persons in the
area.
To ensure personal safety, installation and repair of
LPG/NG fuel supply systems must be performed only
by qualified LPG/NG system technicians. Improperly
installed and maintained LPG/NG equipment could
cause the fuel supply system or other components to
malfunction, causing gas leaks.
Observe federal, state, and local laws governing
LPG/NG fuel, storage, and systems.
K0691
A