CAUTION: TAKE CARE NOT TO OPERATE STEERING WHEEL WITH SHOCK STRUT FULLY EXTENDED AND TORSION LINKS CONNECTED OR DAMAGE TO SHOCK STRUT CENTERING CAMS MAY RESULT.
(c)
Check that hydraulic system A is depressurized.
(d)
Ensure right and left cable guard is 0.015 to 0.045 inch from steering collar pulley. Adjust (Ref 32-51-51 R/I) as required.
(3)
Adjust Nose Wheel Steering System
(a)
Disconnect piston position spring cartridge at quadrant crank (View 1, Fig. 501).
NOTE: Observe position and thickness of washers for use during installation of spring cartridge.
(b)
Rotate piston position quadrant counterclockwise until stop is contacted (shock strut fully compressed direction) and secure quadrant in this position.
(c)
Disconnect rudder pedal steering control rod from rudder pedal steering mechanism (View 2).
(d)
Install rigging pin 1 in quadrant.
(e)
Install rigging pin 2 in steering wheel drum (View 4).
(f)
Install rigging pins 3 in rudder pedal arms (two places).
(g)
Install rigging pin 4 in steering metering valve crank.
(h)
Adjust length of rudder pedal steering control rod so that attachment bolts fit freely. Tighten jamnut and install rod (View 2).
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32-51-0 Page 504 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. May 01/99
CAUTION: END OF ROD END MUST COVER AT LEAST ONE HALF OF INSPECTION HOLES IN CONTROL ROD ASSEMBLY. A MINIMUM OF THREE THREADS MUST BE EXPOSED OUTSIDE LOCKNUT ON CONTROL ROD AT CRANK END TO PREVENT INTERFERENCE AND POSSIBLE ROD FAILURE.
NOTE: On airplanes with 3 hole steering arm, connect rod to center hole.
(i) If new NWSA and NWSB cables have been installed: 1) Rig NWSA and NWSB cables to 120 +12 pounds at 70°F. 2) Remove rigging pins 1, 2, 3, and 4 and cycle piston position system through 25
full cycles (stop to stop) by manually displacing disconnected end of upper
torsion link horizontally.
3) Connect torsion links temporarily with apex bolt.
4) Install rigging pins 1, 2, 3, 4.
(j)
Remove locking clips and adjust tension of all segments of cables NWSA and NWSB to 40 +10/-0 pounds at 70°F ambient temperature. See Table 1 for tension required for other ambient temperatures. Check that all rigging pins are loose.
(k)
Remove bolt connecting steering metering valve rod to steering metering valve crank (Detail A).
NOTE: Steering metering valve is in neutral position when bolt connecting steering metering valve rod to steering metering valve crank fits freely. If bolt does not fit freely, metering valve piston will be held in a position to induce an increment of steering when hydraulic pressure is applied.
Jun 20/92 32-51-0
Page 505
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
(l)
Adjust length of valve rod so that bolt fits freely in valve crank. 1) Loosen jamnuts to disengage locking keys. 2) Hold loose rod end and turn coupling to change length of rod as required. 3) Tighten jamnuts and lockwire.
(m)
Install bolt and tighten nut to 12-15 pound-inches torque.
(n)
On fasteners with holes, install cotter pin. Torque may be increased to 25 pound-inches for hole alignment.
(o)
Install locking clips on turnbuckles of cables NWSA and NWSB.
(p)
Remove all rigging pins. 1) Check that rigging pin 1 is removed from quadrant (View 2). 2) Check that rigging pin 2 is removed from steering wheel drum (View 4). 3) Check that both rigging pins 3 are removed from rudder pedal arms (View 5). 4) Check that rigging pin 4 is removed from steering metering valve crank
(Detail A).
(q)
Release piston position quadrant and rotate quadrant clockwise to align with rod end of piston position spring cartridge.
(r)
Install piston position spring cartridge (View 1).
NOTE: When performing step (q), install washers in same position as observed when removed.
(s)
Test nose wheel steering system per Par. 2.
(t)
Lower airplane and remove jacks (Ref Chapter 7).
2. Nose Wheel Steering System Test
A. General
(1)
The nose wheel steering system is tested to determine if steering rate, steering wheel centering, piston positioning, and angle of travel are within required limits and the system is free of malfunctions and leaks. Prior to conducting the tests, the nose wheel piston positioning and steering systems and the rudder control system must be properly adjusted.
(2)
Prior to conducting the tests, the hydraulic system shall have been serviced per Chapter 12 and the nose wheel steering system properly rigged.
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