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 (1)  Open the cargo door sufficiently to get access to the cargo area.
 NOTE: Manually open the cargo door if the electrical power is off.
____
 S 864-003
 (2)  
Open these circuit breakers for the applicable cargo door and attach DO-NOT-CLOSE tags:

 (a)  
P59 Aft Equipment Panel
 1) AFT CARGO DOOR POWER UNITS

 (b)  
P414 Power Distribution Center - Left 1) 414A21 LOWER CARGO DOOR FWD 2) 414F15 CARGO DOOR CONTROL FWD 3) 414F16 CARGO DOOR CONTROL AFT

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HOOK MECHANISM SEE A
WIRE TO THE HOOK ACTUATOR
FWD 
ACTUATOR 1. HOOK  TUBE 2. TORQUE  HOUSING 4. BEARING 3. CLAMPS  SPRING 5. HOOK RETURN SEE C 
HOUSING 7. PUSHROD 6. BEARING 
BSEE ASSEMBLY RETURN SPRING  HOOK MECHANISM A 9. COUPLINGFWD  8. BELLCRANK 
Figure 401 (Sheet 1) Hook Return Spring 

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4. BEARING 
HOUSING 
8. BELLCRANK 
10. BEARING 
5. HOOK RETURN 
SPRING 
6. BEARING 
HOUSING 
PUSHROD 

SPRING BOLT 11. HOOK RETURN 
3. CLAMP  3. CLAMP  2. TORQUE TUBE 
9. COUPLING 
RETURN SPRING ASSEMBLY B 
Hook Return Spring Figure 401 (Sheet 2) 

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INBD
HOOK RETURN SPRING (VIEW IN THE AFT DIRECTION)

C

1
APPLY A SPRING SCALE FORCE
AT APPROXIMATELY 90` TO THE
CENTERLINE OF THE BELLCRANKS.

Hook Return Spring
Figure 401 (Sheet 3)

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 S 014-004
 (3)  
Remove the lower door lining.

 S 034-005

 (4)  
Remove the torque tube coupling as follows (Fig. 401):

 (a)  
Remove the bolt that connects the pushrod (7) to the bellcrank (8).

 WARNING:_______CAREFULLY LOOSEN THE CLAMPS. IF YOU ARE NOT CAREFUL, THE TENSION IN THE HOOK RETURN SPRING CAN RELEASE QUICKLY AND CAUSE INJURY.

 (b)  
Remove the two bolts which hold each of the two clamps (3) on the torque tube coupling (9).

 NOTE: The torque tube coupling (9) connects the torque
____
 tube (2) and the bellcrank (8).

 (c)  
Hold the bellcrank in its position until the torque tube coupling is removed.

 (d)  
Move the clamps (3) on the torque tube coupling (9) and remove the torque tube coupling (9).

 NOTE: Let the bellcrank (8) turn slowly until the hook return
____
 spring has no tension.

 S 024-006
 (5)  
Remove the hook return spring (5) as follows:

 (a)  
Remove the four bolts that attach the large bearing housing (4) to the cargo door structure.

 (b)  
Move the bearing housing (4) and the bearing (10) on the bellcrank (8).
　
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