THIS CAN CAUSE INJURY TO PERSONS AND DAMAGE TO EQUIPMENT.
 (3)  Supply hydraulic power to the hydraulic systems 1 and 3, or the hydraulic system 2 and 4 (Ref 29-11-00/201).
 S 862-059
 CAUTION:_______MOVE THE RUDDER PEDALS SLOWLY AND SMOOTHLY. THE MINIMUM TIME TO MOVE THE RUDDER THROUGH A FULL CYCLE IS 8 SECONDS. IF YOU MOVE THE RUDDER TOO QUICKLY, THE POWER CONTROL PACKAGE CAN BE DAMAGED.
 (4)  
Operate the rudder until it moves smoothly.

 S 792-060

 (5)  
Examine the rudder PCM for hydraulic leaks.

 S 092-061
 WARNING:_______MAKE SURE THE NOSE WHEELS POINT FORWARD. IF THE NOSE WHEELS DO NOT POINT FORWARD, THE NOSE GEAR CAN QUICKLY TURN TO THE CENTER POSITION WHEN YOU REMOVE THE TOW PIN. THIS CAN CAUSE INJURY TO PERSONS AND DAMAGE TO EQUIPMENT.
 (6)  
Remove the TOW PIN from the nose landing gear (Ref 09-11-00/201).

 S 092-062

 (7)  
Remove the hydraulic power (Ref 29-11-00/201).

 S 642-063

 (8)  
If it is necessary, fill the hydraulic reservoirs (Ref 12-12-01/301).

 S 412-064

 (9)  
Install the access panels (Ref 06-09-07/201).

 (10)
 Remove electrical power if it is not necessary (Ref/24-22-00/201).

 S 862-065
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 LOWER RUDDER HYDRAULIC FUSE - REMOVAL/INSTALLATION
__________________________________________________
 1.  General_______
 A.  There are three tasks in this procedure. There is a task for the removal and a task for the installation of the hydraulic fuse for the lower rudder. There is also a task for the operational test of the hydraulic fuse.
 B.  The hydraulic fuse for the lower rudder is installed in the No. 4 hydraulic system between the rudder/elevator hydraulic shutoff valve and the power control module for the lower rudder.
 TASK 27-21-22-004-003
 2.  Lower Rudder Hydraulic Fuse Removal (Fig. 401)___________________________________
 A.  References
 (1)
12-25-01/301, Exterior Cleaning

 (2)
29-11-00/201, Main Hydraulic Supply System

 B.  
Access

 (1)  
Location Zone
 311 Area Aft of Pressure Bulkhead, LH
 312 Area Aft of Pressure Bulkhead, RH

 (2)  
Access Panel 312A Horizontal Stabilizer Jackscrew Access Door

 C.  
Procedure

 S 864-001
 (1)
Remove the pressure in the hydraulic system (Ref 29-11-00/201).

 (2)
Open the access door 312A to get access to the hydraulic fuse.

 S 024-005

 (3)
Remove the hydraulic fuse:

 (a)
Remove the support clamps from the hydraulic tubes.

 (b)
Loosen the two nuts on the hydraulic fuse.

 S 014-002
 NOTE: Make sure there is no leakage of the hydraulic fluid.
____
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A

747-400
MAINTENANCE MANUAL

SEE  A 
HORIZONTAL STABILIZER 
JACKSCREW ACCESS 
DOOR 312A 
SUPPORT CLAMP 
NUT 
LOWER RUDDER 
HYDRAULIC FUSE 
LOWER RUDDER 
HYDRAULIC FUSE  NUT 
SEE  B 
SUPPORT CLAMP 
HYDRAULIC 
TUBE ASSEMBLY 
FWD 
A  B 
Lower Rudder Hydraulic Fuse 
Figure 401 

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