(2)
AMM 24-22-00/201, Manual Control

 (3)
AMM 27-21-12/501, Rudder Ratio Changer

 (4)
WDM 27-21-12

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 E.  Access
 (1)  
Location Zone
 323 Vertical Fin, Front Spar to Rear Spar
 324 Vertical Fin, Rear Spar to Trailing Edge
 325 Lower Rudder
 326 Upper Rudder

 (2)  
Access Panel
 312A Horizontal Stabilizer Jackscrew Access Door
 324DL Inspection Access Panel
 324FL Centering and Feel Mechanism Access Panel
 324UL Inspection Access Panel

 F.  
Install the Rudder Ratio Changer

 S 222-010
 (1)  
Examine the rod ends of the input and output control rods for worn parts.

 S 422-011

 (2)  
Install the upper (9), or lower (16) RRC.

 (a)  
Align the rudder ratio changer with the airplane structure.

 (b)  
Connect the upper RRC:

 1)  Install the bolts (25, 26, 34, and 35), the washers (17, and 37), and the nuts (18, and 36) to connect the RRC to the airplane.

 (c)  
Connect the lower RRC:

 1)  Install the bolts (38, 39, and 42), the washers (17, and 36), and the nuts (18, and 37) to connect the RRC to the airplane.

 (d)  
Connect the input control rod (8) to the RRC: 1) Install the bolt (19), washer (20), and nut (21).

 (e)  
Connect the output control rod (7) to the summing lever for the power control module. 1) For the upper RRC,

 Install the bolt assembly (3), washer (4), washer (5), and nut (6).
 NOTE: Put the washer (4) below the head of the larger
____ bolt. Put the washer (5) below the nut (6).
 a)  Tighten the larger diameter bolt of the bolt assembly
 (3) to 50-60 pound-inches more than the run-on torque.
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 b)  Tighten the nut (6) to 10-15 pound-inches more than the run-on torque.
 2)  For the lower RRC, Install the bolt (12), washer (13), washer (14), and nut (15).
 NOTE: Put the washer (13) below the head of the larger
____ bolt. Put the washer (14) below the nut (15).
 a)  Tighten the larger diameter bolt of the bolt assembly
 (12) to 50-60 pound-inches more than the run-on torque.
 b)  Tighten the nut (15) to 10-15 pound-inches more than the run-on torque.
 (f)  
On the lower RRC, Connect the electrical connector (41) DM258 to the ratio changer servo (22).

 (g)  
On the upper RRC, Connect the electrical connector (33) DM560 to the ratio changer servo (22).

 (h)  
Install the wire bundle clamp (29) on the RRC.

 (i)  
Install the bolt (30), washer (31), and nut (32) that connects the bonding jumper to the ratio changer servo (22). 1) Use the milliohmmeter to make sure there is a maximum of

 0.01 ohms between the rudder and the vertical fin.
 G.  Put the Airplane Back to Its Usual Condition
 S 862-012
 (1)
Remove the DO-NOT-CLOSE tags and close these circuit breakers:

 (a)  
P7, Overhead Circuit Breaker Panel

 1)  For the lower rudder ratio changer, a) 7B14, LWR RUD RATIO AC PWR b) 7B15, LWR RUD RATIO DC PWR
 2)  For the upper rudder ratio changer, a) 7B12, UPR RUD RATIO AC PWR b) 7B13, UPR RUD RATIO DC PWR
 (b)  P180, DC Power Distribution Panel
 1) 180E7, ELEV/RUD VLV SYS 2
 2) 180E22, ELEV/RUD VLV SYS 4
 3) 180H8, ELEV/RUD VLV SYS 1
 4) 180H23, ELEV/RUD VLV SYS 3
　
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