S 034-010

 (3)  
Disconnect the wires from the limit switch for the ram-air exit door.

 S 034-009
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 21-51-03
 ALL  ú ú 01 Page 404 ú Oct 18/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 S 034-056
 (4)  Remove the remaining sealant from the wires and the limit switch.
 S 034-038
 (5)  Remove the screw (31) and clip (32) from the support bracket.
 S 034-011
 (6)  Remove the retainers (5) from the duct joints of the heat exchanger
 (4 locations).
 S 034-039
 (7)  Pull the sleeves (4) away from the duct joints.
 S 034-013
 (8)  Remove the bolts (9, 11, 13, 26) and the washers (10, 12, 14, 27)
 from the top flange of the heat exchanger.
 NOTE:____ You can get access through the access door in the ram-air
 duct.

 S 034-014
 (9)  
Disconnect the water aspirator fitting (22) from the heat exchanger (21).

 S 034-054

 (10)
 Disconnect the water drain lines from the heat exchanger and the louver assembly.

 S 484-042

 (11)
 Install the lift tool to hold the weight of the heat exchanger.

 S 034-033

 (12)
 Remove the bolts (16, 28), nuts (17, 29), and washers (18, 30) from the support bracket.

 S 024-016

 (13)
 Lower the heat exchanger from the airplane.

 S 034-044

 (14)
 Remove the gasket (24) and filler (15) from the top of the heat exchanger (21).

 S 034-034

 (15)
 Remove the seals (3) and the sleeves (4) from the duct joints.

 S 434-035

 (16)
 Put a cover on the duct openings.

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 21-51-03
 ALL  ú ú 01 Page 405 ú Jun 10/97
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 S 034-043
 (17) If it is necessary, remove the heat exchanger (21) from the ram-air exit door (20).
 (a)  
Remove the heat exchanger (21) from the ram-air exit door (20).

 (b)  
Remove the gasket (23) and filler (25) that were between the heat exchanger (21) and the ram-air exit door (20).

 S 214-037
 (18) Examine the louvers of the ram-air exit door.
 (a)  
If the outboard edge of a louver moves more than 0.20 inches

 (5.1 millimeters), then replace the ram-air exit door.

 (b)  
If a louver has a crack, then replace the ram-air exit door.

 (c)  
To replace the ram-air exit door, you must remove the actuator (Ref 21-62-05/401) and the limit switch (Ref 21-62-12/401) for the exit door.

 TASK 21-51-03-404-021
 3.  Heat Exchanger Installation (Fig. 401)___________________________
 A. Special Tools and Equipment
 (1)  
ME65B40000-1 Heat Exchanger Lifting Tool

 (2)  
2ME65B40006 Heat Exchanger Lifting Tool

 (3)  
Bonding Meter

 B. Consumable Materials
 (1)  
A00247 Sealant, Pressure and Enviromental - Chromate Type - BMS5-95

 (2)  
B00192 Solvent, BMS 3-2, type 1

 (3)  
G00378 Alodine

 (4)  
G00033 Lint-free cheesecloth

 C. References
 (1)  
AMM 20-11-14/701, Metal Surfaces - Cleaning/Painting

 (2)  
AMM 20-22-01/601, Electrical Bonding

 (3)  
AMM 21-00-00/201, Air Conditioning

 (4)  
AMM 21-62-05/401, Ram Air Exit Door Actuator

 (5)  
AMM 21-62-12/401, Ram Air Exit Door Limit Switch

 (6)  
AIPC 21-51-03 Fig. 2

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
　
中國航空網 www.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：747-400 AMM 飛機維護手冊 空調 AIR CONDITIONING 2(14)