One cap is located on the pressure relief valve
on the inboard side of the CNG fuel box, next to
the fuel outlet line. Check the primary relief valve
on the inboard side of the CNG fuel box for signs
of damage or leaks.
7. Check the following components for signs of
damage or leaks.
• Manual fuel shutoff valve
• Fuel cylinder shutoff valves (see
Fig. 11)
• Coolant hoses and fittings
• Fuel lines and fittings
• All fittings, connections, and joints
8. Replace leaking or damaged fuel lines. Repair or
replace leaking or damaged fittings.
47–06 CNG High-Pressure Fuel
Filter Element Replacing
CNG filter element replacement cycles are an
important factor in maintaining the CNG fuel system
integrity and ensuring maximum operating
performance. Actual frequency of the filter element
replacement could increase or decrease depending
on the cleanliness of the fill station fueling system.
1. Shut down the engine and apply the parking
brake.
2. Close the CNG fuel cylinder shutoff valves.
3. Start the engine and let it idle until the fuel lines
are empty and the engine stops. The gauges on
the fuel panel should now read at or near 0 psi.
4. Close the manual fuel shutoff valve on the fuel
panel.
5. Remove the two capscrews that secure the
access cover to the fill panel, then remove the
access cover. See
Fig. 12. Save the capscrews
for reinstallation.
6. Slowly open the bleed valve on the manifold to
relieve remaining fuel pressure within the
system. See
Fig. 13.
05/04/2010 f470555
1
2
33
1. Frame Rail
2. CNG Fuel Cylinder Storage Box
3. Mounting Bolts (qty 12 per side)
Fig. 9, Fuel Cylinder Storage Box Mounting Bracket
(passenger side shown)
H
I
G
H
PR
E
S
S
U
R
E
PR
E
S
S
U
R
E
L
O
W
CYLINDERS
INSPECT CYLINDERS
EVERY 36 MONTHS
OR 36000 MILES
WHICHEVER OCCURS FIRST
NATURAL
GAS
VEHICLE
110 PSIG
ON
M
A
N
U
A
L
S
H
U
T
O
F
F
V
A
L
V
E
OPEN VALVE
SLOWLY
3600 PSIG MAX.
SERVICE PRESSURE
REGULATOR
FILTER
INSPECT PRESSURE
RELIEF DEVICE
EVERY 2000 MILES
DRAIN HOUSING
EVERY 1500 MILES
REPLACE ELEMENT
EVERY 3000 MILES
1
2
3
4
04/30/2010 f470556
1. High Pressure Gauge
2. Low Pressure Gauge
3. Manual Fuel Shutoff Valve
4. Fuel Fill Port and Dust Cap
Fig. 10, CNG Fuel Panel
Fuel 47
Business Class M2 Plus Maintenance Manual, 02/10/2023 47/9
To Next Page
Loading...
