5.
Inspect all vent lines for kinks, and signs of leaks
or damage.
6.
Replace leaking or damaged fuel lines. Repair or
replace leaking or damaged fittings.
Fuel Level Sender Component
Inspecting
1.
Inspect the fuel level sender wiring harness for
signs of loose connections or damage. Look for
cracking or signs of moisture intrusion.
2.
Inspect the fuel level sender box (
, Item 6)
for signs of leaks or damage. Ensure that the
retainer clips are installed on the mounting ears.
3.
Inspect all connectors and wiring for signs of
loose connections, damage, or chafing.
4.
Turn the ignition switch to the ON position and
check for fuel gauge response.
5.
Repair or replace any damaged fuel gauge
components.
Vaporizer Inspecting
See
for plumbing component locations.
1.
Ensure that the vaporizer is secured to its
mounting brackets and that the mounting
brackets are secured to the frame. Inspect for
any signs of looseness.
2.
Inspect the vaporizer fuel inlet and outlet lines for
signs of chafing, damage, or leaks.
3.
Inspect the vaporizer coolant hoses for signs of
chafing, damage, or leaks.
4.
Inspect all fittings for leaks.
5.
Inspect the fuel shutoff solenoid valve for signs
of leaks or damage. Inspect the solenoid mount-
ing bracket for looseness.
6.
Inspect the overpressure regulator for signs of
leaks or damage.
6.1
Ensure that the regulator is mounted se-
curely.
6.2
Check the overpressure regulator fittings
for signs of leaks or damage.
6.3
Ensure that the adjustment handle locking
nut (at the bottom of the overpressure
regulator) is tightened securely.
6.4
Inspect the pressure gauge for damage.
Ensure that the gauge sight glass is clear
and legible.
7.
Repair or replace any leaking or damaged vapor-
izer components.
47–04 LNG Vacuum Integrity
Testing
WARNING
Natural gas is highly flammable. See the safety
precautions listed in Chapter 16 of the
Business
Class® M2 Driver’s Manual
or
Group 47
of the
Business Class® M2 Workshop Manual
. Failure to
observe these precautions could lead to the igni-
tion of the natural gas, which could cause serious
bodily injury or death.
05/05/2010
f470533
1
2
3
4
5
6
7
8
10
11
12
9
1.
Pressure Control
Regulator
2.
Vapor Shutoff Valve
3.
Fuel Fill Hose
4.
Secondary Relief
Valve (red cap)
5.
Fuel Fill Fitting
6.
Fuel Level Sender
Box
7.
Primary Relief Valve
8.
Tank Pressure Gauge
9.
Fill Vent Fitting
10. Excess Flow Valve
11. Fuel Shutoff Valve
(liquid)
12. Fill Check Valve
Fig. 5, Fuel Tank Plumbing Components
Fuel
47
Business Class M2 Maintenance Manual, August 2015
47/6
Property of American Airlines
