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MAINTENANCE MANUAL
FUELING VALVE
OVERFILL TESTSWITCH TEST INDICATOR(3 LOCATIONS)
FUELING VALVE LIGHT
LOAD
SELECT TEST SYSTEM SWITCH
OVERFILL RESET SWITCH
LOAD SELECT CONTROL
BATTERY POWER SWITCH
FUELING CONTROL PANEL, P28
THE UNITS ARE IN LBS OR KGS.
Fueling Control Panel Figure 4A
A07957
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ASEE DRAIN CHECK VALVE ASEE DRAIN CHECK VALVE
TANK SURGE LEFT MAIN FUEL TANK CENTER FUEL TANK FUEL TANK RIGHT MAIN TANK SURGE
AIRPLANE CENTERLINE SEE B FUELING MANIFOLD VENT VALVE 1
MANIFOLD FUELING
BOSS
VENT
NUT AND VALVE
PACKING
FUELING MANIFOLD DRAIN CHECK VALVE
DRAIN HOLE FUELING
DRAIN CHECK VALVE
MANIFOLD
A
FWD INBD
FUELING MANIFOLD VENT VALVE B
Fueling Manifold Drain Check Valve
Figure 5
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(1) Two drain check valves, found in the center fuel tank, attach to the lower side of the fueling manifold. The drain check valves permit drainage of the fueling manifold into the center fuel tank. The drain check valve has an inlet port, outlet port, a hinged flapper, and piston, in its cylindrical housing. The flapper prevents reverse flow of fuel from the fuel tank to the fueling manifold when fuel tank pressure exceeds the manifold pressure. The sliding piston closes the drain check valve when manifold pressure exceeds fuel tank pressure by 8.5 psig or more.
3. Operation (Fig. 6)
_________
A. Functional Description
(1)
The pressure fueling system operates with 28v dc power applied through relays to the fueling shutoff valves. The fuel quantity indicating system (AMM 28-41-00/001) supplies control and indication for pressure fueling.
(2)
Electrical power controls the automatic and manual modes of pressure fueling. The fueling mode is changed between manual and automatic when you push the applicable SET switch on the fueling control panel, P28.
NOTE: When the system is in the automatic mode, the preselected
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