Kohler Decision-Maker 3000 User Manual

166 Section 9 Gas Fuel Systems TP-6356 4/12
9.2 Fuel System Concepts
(Pre-REZG_ and REZX_/RZX_
models)
9.2.1 Gas Fuel System Concept
The gas fuel system utilizes a fuel valve with solenoid to
control the fuel flow to the fuel regulator. The
generator-mounted regulator reduces fuel pressure as
fuel passes to the gas mixer. See Figure 9-5. The gas
mixer controls the ratio of fuel to air under varying load
and speed conditions. Because the gas mixer receives
fuel in a gaseous state, it does not have to perform fuel
vaporization. When switching from natural gas to LP
gas or LP gas to natural gas, VERIFY THAT ENGINE
SPEED MEETS SPECIFICATIONS. The governor
should compensate for different types of fuel and
maintain rated engine speed. See Section 9.5,
Carburetor/Gas Mixer Adjustment, for fuel adjustment
when changing fuel type. If engine speed is incorrect,
refer to the governor information to make adjustments.
1 2 3 4 5
TP-5750-3
1. Primary regulator (supplied by gas supplier or customer)
2. Pressure gauge
3. Solenoid valve
4. Secondary regulator
(shown inverted, position varies by model)
5. Gas mixer
Figure 9-5 Fuel Regulator and Valve, Typical
9.2.2 LP Liquid Withdrawal Fuel System
Concept
With the LP liquid withdrawal fuel system, the tank
directs liquid LP fuel under high pressure to a vaporizer.
The vaporizer converts the liquid fuel to a gaseous state
before sending it to the gas mixer. The system also
includes a fuel valve which shuts off the fuel flow when
the engine stops. See Figure 9-6.
1
2
3
4
TP-5700-6
1. Gas mixer
2. Converter (vaporizer)
3. Solenoid valve
4. LP gas filter (supplied by gas supplier or customer)
Figure 9-6 LP Liquid Withdrawal System, Typical
9.3 LP Gas/Natural Gas
Conversion
9.3.1 Straight Gas Fuel System
Most models operate on either LP gas or natural gas fuel
by performing the fuel conversion procedure. Some
models require a different fuel kit when changing gas
fuels.
Fuel conversion may decrease generator set output and
affect exhaust emissions. Refer to the generator set
spec sheet for ratings.
By performing the fuel conversion, some models can
operate on either natural gas or LP gas fuel. The
conversion may require addition/removal of the fuel
regulator spring and retainer. See Figure 9-7 for
specific information regarding conversion options. See
Section 9.8, Engine Ignition Timing, for engine timing
information.
Generator
Set Model,
kW
Engine
Spring Position
Additional
Adjustments
and Comments
Natural
Gas
LP
Gas
20
Ford
LRG-425
In Out See Section 9.8
30--125
GM 3.0 L,
4.3 L, 5.0 L,
5.7 L, 8.1 L,
8.1 L Turbo
In Out
Adjust fuel mixture
and timing. See
Sections 9.9, 9.10,
9.11, and 9.12
135--180
Detroit Diesel
Series 50
— — Natural gas only
200--275
Detroit Diesel
Series 60
— — Natural gas only
400--800 Waukesha — — Natural gas only
* Some models require new fuel kits for fuel conversion.
Figure 9-7 Fuel Conversion Data

Kohler Decision-Maker 3000 Specifications

General

Brand	Kohler
Model	Decision-Maker 3000
Category	Controller
Language	English