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A
747-400 MAINTENANCE MANUAL
UPPER GIMBAL
SEE B
SEE A
DRIVE
MECHANISM

SEE C
SEE D UPPER GIMBAL
A
ZERK
MIL-G-23827
(2 LOCATIONS) 1 (FORWARD AND AFT)
BALLNUT SCREW ZERK
MIL-G-23827
(1 LOCATION) (FORWARD)
UPPER GIMBAL
5 POINTS
B
1 ONE MORE LOCATION IS ON THE OPPOSITE SIDE SHOWN. Stabilizer Control System Lubrication Figure 301 (Sheet 1)
LUBRICATION VENT PLUG
1
UPPER GIMBAL SAFETY SHAFT ZERK
MIL-G-23827
(2 LOCATIONS)
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A
747-400 MAINTENANCE MANUAL
STABILIZER JACKSCREW
DIFFERENTIAL
HOUSING HYDRAULIC BRAKES DRIVE MECHANISM
FILL
MIL-H-5606
1 (2 LOCATIONS)
ANTIROTATION CABLE
LOWER GIMBAL
HYDRAULIC MOTORS
2 POINTS
D
Stabilizer Control System Lubrication Figure 301 (Sheet 2)
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LOWER GIMBAL 
SAFETY PIN 
LOWER GIMBAL 
1  SAFETY SHAFT 
ZERK 
HYDRAULIC  MIL-G-23827 
MOTORS  (2 LOCATIONS)  LOWER GIMBAL 
ZERK 
STABILIZER TRIM  MIL-G-23827 
DRIVE MECHANISM  1  (2 LOCATIONS) 
4 POINTS 
C 

A 747-400 MAINTENANCE MANUAL
 S 863-003
 (2)  Pressurize the hydraulic systems No. 2 or 3 (Ref 29-11-00/201).
 S 013-005
 (3)  Open the 312A access door (Ref 06-09-07/201).
 S 643-024
 (4)  Lubricate the safety shafts of the upper and lower gimbal (Fig. 301).
 S 643-025
 (5)  Lubricate the upper and lower gimbals (Fig. 301).
 S 643-006
 (6)  Lubricate the jackscrew upper ballnut and the stabilizer trim jackscrew (Fig. 301). (a) Hold the STAB TRIM ALTN switches to APL NOSE DN until the stabilizer position indicators show APL NOSE DN. (b) Set the STAB TRIM 2 and 3 switches on the control stand to CUTOUT.
 (c)  Lubricate the ballnut zerk fitting until the grease goes out of the two lower drain holes.
 (d) (e) (f)  Set the STAB TRIM 2 and 3 switches on the control stand to ON.Use the STAB TRIM ALTN switches on the control stand to set the stabilizer to approximately 3 units of trim.Set the STAB TRIM 2 and 3 switches on the control stand to CUTOUT.
 (g)  Lubricate the ballnut zerk fitting until the grease goes out of the two lower drain holes.
 (h) (i) (j)  Set the STAB TRIM 2 and 3 switches on the control stand to ON.Use the STAB TRIM ALTN switches on the control stand to set the stabilizer to approximately 6 units of trim.Set the STAB TRIM 2 and 3 switches on the control stand to CUTOUT.

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

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A
747-400
MAINTENANCE MANUAL

 (k)  
Lubricate the ballnut zerk fitting until the grease goes out of the two lower drain holes.

 (l)  
Set the STAB TRIM 2 and 3 switches on the control stand to ON.

 (m)  
Use the STAB TRIM ALTN switches on the control stand to set the stabilizer to approximately 9 units of trim.

 (n)  
Set the STAB TRIM 2 and 3 switches on the control stand to CUTOUT.

 (o)  
Lubricate the ballnut zerk fitting until the grease goes out of the two lower drain holes.