(c)  
Select the PREV PAGE twice on the MCDU.

 (d)  
Make sure that the status of bit 21 on the MCDU display of label 270 on page 1 is a 0.

 (e)  
Select the NEXT PAGE on the MCDU.

 (f)  
Make sure that the status of bit 21 on the MCDU display of label 272 on page 2 is a 1.

 (g)  
Make sure that the EICAS message NOSE AIR/GROUND DISAGREE comes into view on the lower EICAS display.

 (h)  
Move the EIU select switch to the C position.

 (i)  
Make sure that the NOSE AIR/GROUND DISAGREE comes into view on the EICAS.

 (j)  
Move the EIU select switch to the R position.

 (k)  
Make sure that the NOSE AIR/GROUND DISAGREE comes into view on the EICAS.

 E.
Put the Airplane in its Usual Condition

 (1)  
Install the second center ceiling panel, aft in Zone A.

 S 864-014

 (2)  
Remove the electrical power if it is not necessary
 (AMM 24-22-00/201).

 S 414-009
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

SEE B
SEE A
MOUNTING SCREW 
(2 LOCATIONS) 
ELECTRICAL  BRACKET 
CONNECTORS  ASSEMBLY 
A 

WASHER (2 LOCATIONS)
NUT (2 LOCATIONS)

B
Rudder Pedal Steering Indicator Switch Installation Figure 401
C26037
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 STEERING METERING VALVE - REMOVAL/INSTALLATION
______________________________________________
 1.  General
_______
 A.  This procedure contains two tasks:
 -Removal of the steering metering valve
 -
Installation of the steering metering valve.

 B.
The steering metering valve is a slide and sleeve type hydraulic valve.

 (1)  
It is on the aft side of the nose gear shock strut above the wheels.

 (2)  
It contains two swivel valves and a bypass valve.

 (a)  
The swivel valves supply fluid during turning. 1) Each swivel post is matched to its related swivel valve housing to control clearances and flow properties.

 2)  Mismatched parts can be found by comparing their serial numbers. a) The serial number on each swivel post must be the same
 as the serial number on its housing.
 (b)  
The bypass valve prevents system damage, because of high pressures, during airplane towing.

 C.  
To remove the metering valve these steps are necessary:

 -
Remove valve cover and bracket

 -
Remove bolts connecting valve to steering actuator

 -
Unscrew retainer nuts and remove valve.

 D.  
To install the metering valve these steps are necessary:

 -Align holes on valve with holes on support plate and install valve attach bolts
 -Tighten retainer nuts
 -Seal metering valve
 -Install bracket and cover
 -Do a check of the metering valve.
 TASK 32-51-04-004-001
 2.  Steering Metering Valve Removal
_______________________________
 A.  Special Tools and Equipment
 (1)  G12001 - Rigging Pins Rigging Pin NS-5 0.311 (+0.000/-0.002)-inch diameter, 4.00-inch length Rigging Pin NS-6 - 0.188 (+0.000/-0.002)-inch diameter, 2.50-inch length
 NOTE: Rigging pin is part of G12001 tool kit
____
 (2)  
3MIT65B01519-1 - Torque Wrench Adapter

 (3)  
3MIT65B01519 - Bearing Puller

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