B.
Access

 (1)  
Location Zones 131 Center Section Wing Box, Left 132 Center Section Wing Box, Right 542 Inbd Main Tank (Part), Front Spar to Mid Spar, Left 544 Inbd Main Tank (Part), Mid Spar to Rear Spar, Left 552 Outbd Main Tank (Part), Mid Spar to Rear Spar, Left 553 Reserve Tank, Front Spar to Rear Spar, Left 642 Inbd Main Tank (Part), Front Spar to Mid Spar, Right 644 Inbd Main Tank (Part), Mid Spar to Rear Spar, Right 652 Outbd Main Tank (Part), Mid Spar to Rear Spar, Right 653 Reserve Tank, Front Spar to Rear Spar, Right

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 28-13-02
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A
747-400
MAINTENANCE MANUAL

 (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
 552AB Fuel Tank Access Door
 552FB Fuel Tank Access Door
 652AB Fuel Tank Access Door
 652FB Fuel Tank Access Door

 C.
Procedure

 S 654-016
 (1)  Defuel the applicable fuel tank (Ref 28-26-00/201).
 S 864-034
 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 OBEY THE SAFETY PROCEDURES.
 (2)
Purge and prepare to go into the fuel tank (Ref 28-11-00/201).

 S 014-018

 (3)  
Remove more tank access doors, if it is necessary, to get access to the float valve that is to be disassembled (Ref 28-11-02/401).

 NOTE: Refer to this table for access door locations.
____
 ~................................................................. | Location | Access Door | ................................................................... | No. 1 Main Tank - Middle | 552AB | | No. 1 Main Tank - Outbd | 552GB | | No. 2 Main Tank | 545BB | | No. 3 Main Tank | 645BB | | No. 4 Main Tank - Middle | 652AB | | No. 4 Main Tank - Outbd | 652GB | | No. 2 Reserve Tank | 553KB | | No. 3 Reserve Tank | 653KB | | Center Wing Tank | 131EZ | 2......................................…..........................1
 S 864-019
 (4)  Go into the fuel tank (Ref 28-11-00/201).
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 S 014-020
 (5)  
If you remove the float assembly from the float valve in the center wing tank, remove the spanwise beam access doors, 131AZ, 131BZ, and 131CZ (left side) or 131AZ, 131BZ, and 132AZ (right side) (Ref 28-11-09/401).

 S 034-021

 (6)  
Remove the lockwire from the hinge pin (3).

 S 034-032

 (7)
Remove the washers (4) from the ends of the hinge pin (3).

 S 034-022

 (8)  
Hold the float assembly (1) and move the hinge pin (3) out of the valve flange and float arm brackets.

 S 024-023

 (9)  
Move the float assembly (1) apart from the valve flange.

 S 034-035

 (10)
 Keep the teflon washers (2).

 TASK 28-13-02-404-024
 5. Fuel Vent Valve Poppet and Float Assembly Installation (Fig. 402)
______________________________________________________
 A. Parts
 ~.............................................................................. | MM | | IPC | ................. ............................ | FIG | ITEM | NOMENCLATURE | SUBJECT | FIG | ITEM | ................................................................................ | 401 | 1 | Poppet and Float Assembly | 28-13-01 | 01 | 242 | | | | | 28-13-02 | 02 | 185 | | | 2 | Washer (Teflon Washer) | 28-13-01 | 01 | 236 | | | | | 28-13-02 | 02 | 180 | | | 3 | Pin (Hinge Pin) | 28-13-01 | 01 | 233 | | | | | 28-13-02 | 02 | 170 | | | 4 | Washer | 28-13-01 | 01 | 239 | | | | | 28-13-02 | 02 | 175 | 2......…........…...................................…..........….....….........1
　
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