Fuel System Intermittent Problems; Fuel System Basic Checks - Kohler KG2204 Service

3.1. Fuel System Intermittent
Problems
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.
Definition: The problem is not always observable and
may or may not store a Diagnostic Trouble Code
(DTC).
Intermittent fuel system problems can be the most
challenging to diagnose. It is important when
diagnosing intermittent problems to operate the engine
system while monitoring with Spectrum software and a
pressure gauge set.
For example: If a lean fuel mixture at full load
produced a DTC, one of the first things to look at would
be the fuel pressure. The fuel pressure would need to
be monitored with Spectrum while the engine is
operating at full load, not at low or no load because the
leaning effect does not occur until full load.
TP-6903 5/16a

3.2. Fuel System Basic Checks

When checking for air or fuel delivery problems, keep
the process simple and check the basics. Make sure
that air and fuel are being delivered to the fuel
regulator.
Use a manometer to verify fuel pressure at the
fuel pressure port. Fuel delivery to the engine
must be between 5-11 inches water at all times.
1. Fuel pressure ports
Figure 3-1 Fuel Shut-off Valve
1
1. Fuel pressure ports, one on each side
Figure 3-2 Dual-Solenoid Fuel Valve
Verify that both fuel shut-off valves are working.
a. Disconnect the positive (+) battery lead from
the gas valve terminal.
b. Apply 12 VDC to the gas valve terminal and
listen for an audible click, indicating that the
valve actuates.
c. Replace the gas valve if it does not actuate in
step 2.
Verify that the fuel pressure regulator is working
and is set correctly for the fuel type used, NG or
LPG.
To check the inlet pressure, connect a
manometer to the inlet port of the fuel pressure
regulator. See Figure 3-3.

NG = 5–11 inches of water pressure

LPG = 5–11 inches of water pressure
1
Fuel System Troubleshooting 47