27-21-12
 ALL  ú ú 01 Page 204 ú Jun 20/93
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A

757 MAINTENANCE MANUAL
CONTROL RODS TO THE RUDDER RATIO CHANGER
RUDDER MIDDLE POWERRATIO CHANGER
CONTROL ACTUATOR SEE C
SEE B
FEEL,
CENTERING, AND
TRIM MECHANISM

RIG PIN HOLE R3
SEE A
FEEL, CENTERING, AND TRIM MECHANISM
A
YAW DAMPER SUMMING LINKAGE
RIG PIN HOLE R4
UP
POGO  FWD
RIG PIN HOLE R7
RUDDER RATIO CHANGER
MIDDLE POWER CONTROL ACTUATOR RUDDER RATIO CHANGER
B C Rig Pin Locations Figure 202
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 27-21-12
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757 MAINTENANCE MANUAL
 S 012-019
 (6)
Open access panels 324AL, 324BL, and 324CL (Ref 06-42-00).

 F.
Remove Rudder Ratio Changer

 S 492-020
 (1)
Install these rig pins:

 (a)
R3 (for the feel, centering, and trim mechanism).

 (b)
R4 (for the middle power control actuator).

NOSE GEAR TOWING LEVER LOCKPIN
FWD  POSITION) TOWING LEVER (IN THE TOW 
TOWING LEVER ASEE  TOWING LEVER
A 
Figure 203 Nose Gear Steering Isolation 

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757 MAINTENANCE MANUAL
 (2)  S 022-021Remove the ratio-changer actuator (1) (Ref 27-21-13).
 (3)  S 032-022Remove the lockwire from the LVDT electrical connectors (38).
 (4)  S 032-023Disconnect the LVDT electrical connectors (38) and tag them for identification.
 (5)  S 032-024Remove these components: (a) Remove the bolt that connnects the pogo (8) to the summing lever. (b) Remove the bolt that connects the control rod (2) to the summing lever. (c) Use the removal procedure below to remove the shear pin (4) that connects the control rod (2) to the right ratio-changer output crank. (d) Remove the bolt (9) that connects the pogo (8) to the left ratio-changer output crank. Remove the pogo.
 (6)  S 032-025Disconnect the control rods that are connected to the feel, centering, and trim mechanism (21) from the ratio-changer mechanism.
 (7)  S 032-026Do these steps to disconnect the ratio-changer mechanism (13) from its brackets (24, 32). (a) Remove the outer and inner nuts (28, 30) from the left and right brackets (24, 32). (b) Remove the bolt assembly (26), bushing (27), and the bearing (38) from the right bracket (24). (c) Remove the bolt assembly (26) and the bushing (33) from the left bracket (32).

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757 MAINTENANCE MANUAL
 S 032-027
 (8)  Remove the ratio-changer actuator mount (16).
 NOTE: Keep the shims that were installed.
____
 S 022-028
 (9)  
Remove the ratio-changer mechanism (13).

 G.
Remove the Shear Pin from the Ratio-Changer Mechanism (Fig. 204)

 S 332-029
 (1)  Use a drill to remove the rivet that holds the shear pin retainer to the right ratio-changer output crank. Be careful not to damage the retainer or the right ratio-changer output crank. Remove the shear pin retainer.
 NOTE: Keep the shims that were installed.
____
 S 332-030
 (2)  Use a drill to remove the shear pin from the retainer side. Be careful not to damage the bushing in the right ratio-changer output crank or the rod end bearing.
 NOTE: Use a drill bit larger than 3/16 inch but smaller than
　
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