Alpha Technologies AlphaGen 3.5_5.0kW Kohler COM5 - Manual (Page 49)

TP-6482 8/06 49 Section 5 Component Testing and Adjustment
5.7.1 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).
Do not try to adjust the fuel pressure, fuel mixture, or
engine speed using the fuel lock-off. See Figure 5-20
for the location of the fuel lockoff. The fuel lock-off
prevents fuel flow when the engine is not operating.
Checking the Fuel Pressure
Use a gauge or manometer to check the fuel pressure at
the secondary regulator inlet.
See Figure 5-20.
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.
Note: Do not attempt to adjust the fuel mixture or engine
speed by adjusting the regulators.
4
6
3
1. Secondary pressure regulator
2. Dual-fuel block
3. Carburetor
4. Inlet pressure check location (plug)
5. Fuel inlet
6. Fuel metering valves
7. Fuel lockoff (Do not adjust.)
GM14140B-K
1
7
2
5
Top View
End View
Side View
Side View
Figure 5-20 Fuel System