SEE A
1. COOLING AIR INLET SCREEN
4A. NUT (4 LOCATIONS) FWD
APU COMPARTMENT
3.
 WASHER (4 LOCATIONS)

4.
 AIR INLET PLENUM

4B. DUCT
2. BOLT ADAPTER
(4 LOCATIONS)
FWD
5.
 COOLING AIR INLET DUCT

6.
 CLAMP

COOLING FAN
A
Cooling Air Inlet Screen Installation
Figure 401

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A
747-400 MAINTENANCE MANUAL
 (c)  Remove the clamp (6), cooling air inlet duct (5) and cooling air inlet screen (1) from the APU compartment.
 NOTE: You remove the cooling air inlet duct (5) and cooling
____ air inlet screen (1) as an assembly.
 (d)  
Remove the cooling air inlet screen (1).

 (e)  
Make sure you install all necessary protection covers.

 TASK 49-51-04-404-011
 3. Cooling Air Inlet Screen Installation (Fig. 401)
_____________________________________
 A. Parts ~.............................................................................. | AMM | | AIPC | ................. ............................ | FIG | ITEM | NOMENCLATURE | SUBJECT | FIG | ITEM | ................................................................................ | 401 | 1 | Cooling Air Screen Assembly | 49-51-01 | 01 | 175 | | | | (Cooling Air Inlet Screen) | | | | 2.......….......…...................................…...........…......….......1
 B. Access
 (1)  
Location Zones
 221 Control Cabin - Left
 222 Control Cabin - Right
 310 Fuselage - Station 2360 to Station 2792

 (2)  
Access Panels
 317AL APU Access Door - Left
 318AR APU Access Door - Right

 C.
Procedure

 S 424-007
 CAUTION: MAKE SURE YOU DO NOT HIT THE AIR INLET PLENUM WITH YOUR HANDS
_______ OR YOUR TOOLS. DAMAGE TO THE AIR INLET PLENUM CAN OCCUR.
 CAUTION: REMOVE THE PROTECTION COVERS FROM THE OPENINGS AS NECESSARY.
_______ IF YOU DO NOT REMOVE THE PROTECTION COVERS, DAMAGE TO THE APU CAN OCCUR.
 (1)
Do these steps to install the cooling air inlet screen (1):

 (a)  
Put the clamp (6) loosely over the flange of the cooling fan.

 (b)  
Put the cooling air inlet screen (1) and cooling air inlet duct

 (5)
 on the cooling fan and air inlet plenum (4).

 (c)  
While you align the holes of the cooling air inlet screen (1), duct adapter (4B) and air inlet plenum (4), install the four bolts (2), four washers (3) and four nuts (4A). 1) Tighten the four nuts (4A) with your fingers.

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747-400
MAINTENANCE MANUAL

 (d)  While you align the cooling air inlet duct (5) with the cooling fan, install the clamp (6) over the flanges of the cooling air inlet duct and cooling fan.
 NOTE: It is recommended that you install the clamp (6) with
____ the clamp screw on the forward right side of the APU. You tighten the clamp screw until the clamp can sufficiently hold the cooling air inlet duct and cooling fan together.
 (e)  
Tighten the four nuts (4A) to 36-40 inch-pounds (4.1-4.5 newton-meters).

 (f)  
Tighten the clamp screw on the clamp (6) to 12-18 inch-pounds (1.4-2.0 newton-meters).

 D.
Put the Airplane Back to Its Usual Condition

 S 864-013
 (1)
Remove the DO-NOT-CLOSE tags and close these circuit breakers:

 (a)  
P6-2 Main Power Distribution Panel
 1) 6K18, APU ALTN CONT

 (b)  
P83 Aft APU Equipment Control and Circuit Breaker Panel 1) APU PRIME CONT
　
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