Kohler 11RMY Service Manual

TP-5867 11/02 53Section 6 Component Testing and Adjustment
6.11 Fuel Systems
Single-fuel systems are factory-adjusted for either
natural gas or LP vapor. Check the generator set
nameplate to determine which fuel the unit uses.
Multi-fuel systems are factory-adjusted for both natural
gas and LP vapor.
The fuel supplier provides and maintains manual
shut-off valves and the primary regulator. A
factory-installed secondary regulator and 12 VDC
solenoid valve are located in the front inlet air
compartment. The controller energizes the fuel
solenoid valve to open at start and deenergizes the
valve to close at shutdown. The secondary fuel
regulator reduces fuel pressure for delivery to the fuel
metering (fuel mixture adjustment) valve. The fuel flows
from the metering valve to the carburetor in a gaseous
state. The carburetor mixes the fuel with intake air for
consumption by the engine.
Refer to the troubleshooting instructions in Section 3,
Troubleshooting, to identify generator set operation
problems that may be caused by an inadequate fuel
supply or incorrectly adjusted or faulty fuel system
components. Then use the instructions in this section to
check fuel system components.
6.11.1 Gas Piping
Verify that the gas pipe size meets the size
specifications in Figure 6-25. Measure the pipe length
from the gas utility pressure regulator to the end of the
pipe where it connects to the fuel inlet of the generator
set. Add 2.4 m (8 ft.) for each bend in the pipe.
Compare the total length with the chart in Figure 6-25.
Replace piping longer than the listed maximum length
with the larger pipe size shown in the chart. Bleed the air
from the gas lines after installation.
Figure 6-26 lists the maximum natural gas flow rate for
each model.
Maximum Pipe Length m (ft.)
Pipe Size
8.5RMY 11RMY
3/4 in. NPT 18.3 (60) 9.2 (30)
1 in. NPT 61 (200) 30 (100)
1 1/4 in. NPT 91.5 (300) 68.6 (225)
Figure 6-25 Maximum Natural Gas Pipe Length
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Set Model
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Btu/hr.
8.5RMY 132,000
11RMY 192,000
Figure 6-26 Maximum Natural Gas Flow Rate
6.11.2 Fuel Solenoid Valve
A solenoid valve upstream of the regulator and the
flexible fuel connector provides automatic fuel on/off
control. The engine starting battery powers the solenoid
valve and the engine starting controls open the valve
when the engine cranks or runs.
Gas Valve Operation Test Procedure
1. Disconnect the positive (+) battery lead from the
gas valve terminal.
2. Apply 12 VDC to the gas valve terminal and listen
for an audible click, indicating that the valve
actuates.
3. Replace the gas valve if it does not actuate in
step 2.
6.11.3 Fuel Regulators
The typical gaseous fuel system uses two regulators.
The primary regulator reduces the line pressure to an
allowable inlet pressure for the secondary regulator.
The fuel supplier provides and maintains the primary
regulator. The secondary regulator is factory-installed
on the generator set and is designed for a maximum inlet
pressure of 2.7 kPa (6 oz./in.
2
) or 280 mm (11 in.) water
column.
Note: Do not attempt to adjust the fuel mixture or engine
speed by adjusting the regulators.
The fuel lock-off prevents fuel flow when the engine is
not operating. See Figure 6-27. Do not try to adjust the
fuel pressure, fuel mixture, or engine speed using the
fuel lock-off.
Checking the Fuel Pressure
Use a gauge or manometer to check the fuel pressure at
the secondary regulator inlet. See Figure 6-27.
Measure the fuel pressure with the generator set
running at full load. The fuel pressure should be
178--280 mm (7--11 in.) water column or 1.7--2.7 kPa
(4--6 oz./in.
2
). Contact the fuel supplier if the inlet
pressure is not within the specified range.

Kohler 11RMY Specifications

General

Brand	Kohler
Model	11RMY
Category	Portable Generator
Language	English