C.  
Procedure

 (1)
Remove the jettison transfer valve actuator (AMM 28-31-04/401).

 (2)
Defuel the center wing tank (AMM 28-26-00/201).

 S 014-002
 S 654-003
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A
747-400 MAINTENANCE MANUAL
 S 864-041
 WARNING: DO NOT REMOVE THE FUEL JETTISON TRANSFER VALVE FROM THE CENTER
_______ WING TANK IF THE NO. 2 OR NO. 3 MAIN TANK FUEL LEVELS ARE MORE THAN 1050 GALLONS-7000 LBS (3860 LITERS-3100 KGS). VALVE REMOVAL WILL CAUSE FUEL LEAKAGE INTO THE CENTER WING TANK AND THROUGH THE CENTER WING TANK ACCESS DOOR AND COULD CAUSE AN EXPLOSION.
 (3)  
Make sure the fuel level in No. 2 and No. 3 main tanks is not more than 1050 gallons-7000 lbs (3860 liters-3100 kgs).

 (a)  
If the fuel level is more than this limit, decrease the fuel level to 1050 gallons-7000 lbs (3860 liters-3100 kgs) or less (AMM 28-26-00/201).

 S 864-031
 WARNING: CAREFULLY DO ALL THE SAFETY PROCEDURES TO DEFUEL AND GO INTO
_______ THE FUEL TANKS. INJURY TO PERSONS AND DAMAGE TO EQUIPMENT CAN OCCUR IF YOU DO NOT FOLLOW THE SAFETY PROCEDURES.
 (4)  
Purge and go into the fuel tank (AMM 28-11-00/201).

 S 014-007

 (5)  
Remove the spanwise beam access doors (AMM 28-11-09/401).

 (a)  
For the left valve body, remove the spanwise beam access doors 131AZ, 131BZ, 131CZ, and 131DZ.

 (b)  
For the right valve body, remove the spanwise beam access doors 131AZ, 131BZ, 132AZ, and 132BZ.

 S 034-008
 (6)  
From out of the tank, remove the mounting bolts and washers (4 locations) that attach the valve body to the rear spar.

 S 034-009

 (7)  
Remove the bolts and washers (12 locations) that connect the valve body to the discharge line.

 (8)  
Remove the valve body from the tank.

 S 024-010
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747-400 MAINTENANCE MANUAL
 S 034-033
 (9)  
Discard the gaskets between the valve body and the discharge line.

 S 034-034

 (10)
 Discard the gasket seal between the valve body and the rear spar.

 TASK 28-31-06-404-011
 3.  Fuel Jettison Transfer Valve Body in the Center Wing Tank Installation______________________________________________________________________ (Fig. 401)
 A.  References
 (1)  
AIPC 28-31-06 Fig. 5

 (2)  
AMM 12-11-01/301, Fuel Servicing

 (3)  
AMM 28-11-00/201, Fuel Tanks

 (4)  
AMM 28-11-09/401, Spanwise Beam Access Door

 (5)  
AMM 28-31-04/401, Jettison Transfer Valve Actuator

 B.  
Access

 (1)  
Location Zones
 131 Center Section Wing Box, Left
 132 Center Section Wing Box, Right

 (2)  
Access Panels
 131AZ Spanwise Beam Access Door
 131BZ Spanwise Beam Access Door
 131CZ Spanwise Beam Access Door
 131DZ Spanwise Beam Access Door
 132AZ Spanwise Beam Access Door
 132BZ Spanwise Beam Access Door

 C.  
Procedure

 S 164-012
 (1)  
Clean the seal surfaces on the valve mounting flange and the rear spar.

 S 424-013

 (2)  
Hold the valve body and a new gasket seal in their positions on the rear spar in the tank.

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