NOTE: DUAL CROSSFEED CONFIGURATION.
Pressure Fueling System
Figure 1A
H44194
A
757
MAINTENANCE MANUAL
ELECTRICAL
ADAPTER CONNECTOR
PLATE
ADAPTER SHAFT
UNIVERSAL
JOINT
ACTUATOR
SHUTOFF VALVE ENGINE FUEL MANUAL OVERRIDE HANDLE
SEE A FUEL
LINE
FWD INBD REAR SPARVALVE (DRY SIDE)BODY
ENGINE FUEL SHUTOFF VALVE A1
ELECTRICAL
ADAPTER CONNECTOR
PLATE
FUEL LINE ADAPTER SHAFT
UNIVERSAL JOINT
VALVE SPLINES ACTUATOR
MANUAL
OVERRIDE
HANDLE
FWD INBD
REAR SPARVALVE (DRY SIDE)BODY
ENGINE FUEL SHUTOFF VALVE
1
PREFERRED A 2 2
ALTERNATE
Engine Fuel Shutoff Valve Figure 2
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28-22-00
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A
757
MAINTENANCE MANUAL
(2)
The square (preferred) actuator, has a 28v dc permanent magnet motor, an electrical connector, "OPEN-CLOSED" limit switches, and a manual override handle. The manual override handle also shows the position of the engine fuel shutoff valve.
(3)
The round (alternate) actuator consists of a 28 vdc motor, an electrical connector, open-closed limit switches, and a manual override handle which also serves as a valve position indicator.
(4)
The adapter shaft connects the actuator and the valve body. The adapter shaft consists of an adapter plate and a shaft with a universal joint. The adapter shaft has indexed splines at both ends. This ensures correct alignment between the actuator and the valve. Access to the adapter shaft requires defueling.
(5)
The thermal relief valve(s) on the valve body, crack and reseat between 70 to 55 psig.
(6)
Applying 28vdc power opens or closes the valve, depending upon the command. Upon reaching open position, the butterfly plate contacts a stop pin to prevent over-travel. With the valve full OPEN, the open limit switch closes to deenergizing the actuator. Upon reaching the full CLOSED position, the butterfly plate contacts a stop pin to prevent over-travel. This closes the closed limit switch and deenergizes the actuator.
(7)
The valves allow or prevent fuel from flowing to the engines.
B.
Engine Fuel Crossfeed Valve (Fig. 3, 3A)
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