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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A 737-300/400/500MAINTENANCE MANUAL
 3.  Nose Gear Steering Collar
_________________________
 A.  The nose gear steering collar is at the middle of the outer cylinder (Fig. 1). The collar is held clamped around the outer cylinder, by a bolt, in an annular recess immediately below the trunnions. Both of the two steering cylinders are connected to the steering collar and the upper end of the upper torsion link is also connected to the steering collar. When force is applied to the steering collar, by either steering cylinder, the collar transfers the force through the torsion links to turn the inner cylinder to the right or left respectively to which cylinder force is applied to give steering action to the nose wheels.
 4.  Nose Gear Torsion Links
_______________________
 A.  The nose gear torsion links allow rotation between the inner and outer shock strut cylinders only when moved by the steering collar or when disconnected. The upper link is connected to the steering collar, and the lower link is connected to a lug on the inner cylinder (Fig. 1). The upper and lower torsion links are joined together by an apex pin. This locks the nose wheels in the position assumed by the steering collar without affecting strut action. Steering forces applied to the steering collar by the nose gear steering system are transmitted to the inner cylinder by the torsion links.
 5.  Nose Gear Drag Brace
____________________
 A.  The nose gear drag brace, in conjunction with the nose gear lock link assembly, holds the nose gear in the up or down locked position (Fig. 3). The drag brace consists of an upper and lower link. The upper end of the upper link pivots on pins through support fittings attached to the wheel well sidewalls. During gear retraction, the upper link rotates upward and aft. The lower end of the lower link pivots about a pin which attaches the lower link to double lugs on the outer cylinder. These lugs are located just above the steering collar. During gear retraction, the lower link also rotates upward and aft relative to a pivot point. The upper and lower links are bolted together forming a hinge.
 B.  A fitting located near the lower end of the upper drag link, containing a spherical bearing, is the attachment point for the nose gear actuator. During gear retraction, the upper drag link is forced to rotate upward and aft by the nose gear actuator. This motion is transmitted to the shock strut through the lower drag link to raise the gear to the up position.
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A 737-300/400/500MAINTENANCE MANUAL
NOSE GEAR
ACTUATOR
DOOR OPERATOR MECHANISM
TRUNNION
NOSE WHEEL
WELL DOOR
SHOCK STRUT
DOOR OPERATOR MECHANISM
NOSE WHEEL
WELL DOOR
UPPER DRAG
BRACE LINK

LOWER DRAG
BRACE LINK

STEERING
CYLINDER

NOSE GEAR ACTUATOR
UPPER DRAG
BRACE LINK
LOCK MECHANISM
LOWER DRAG BRACE LINK
LOCK
ACTUATOR
TRUNNION
TORSION LINKS
GEAR IN TRANSIT

Nose Gear Drag Brace
Figure 3

NOSE GEAR
ACTUATOR

DOOR OPERATOR
MECHANISM

LOWER DRAGNOSE WHEEL BRACE LINKWELL DOOR STEERING CYLINDER
GEAR EXTENDED
NOSE GEAR ACTUATOR
DOOR OPERATOR MECHANISM
NOSE WHEEL
WELL DOOR TORSION LINKS
GEAR RETRACTED
UPPER DRAG
BRACE LINK
LOCK MECHANISM
LOCK ACTUATOR
TRUNNION
SHOCK STRUT
TORSION LINKS
UPPER DRAG
BRACE LINK
LOCK MECHANISM
LOWER DRAG BRACE LINK
LOCK ACTUATOR
TRUNNION
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 32-21-00
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
737-300/400/500MAINTENANCE MANUAL
 NOSE LANDING GEAR - REMOVAL/INSTALLATION
________________________________________
 1. General
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