(6)  
AMM 32-32-15/401, Truck Positioner Actuator

 (7)  
AMM 32-32-17/401, Truck Positioner Shuttle Valve

 B.  
Access

 (1)  
Location Zones
 211 Control Cabin (Left)
 212 Control Cabin (Right)
 551 Wing Trailing Edge (Left)
 651 Wing Trailing Edge (Right)

 C.  
Prepare for Leak Check

 S 485-029
 WARNING: MAKE SURE THE DOWNLOCKS ARE INSTALLED IN ALL THE LANDING GEAR
_______ BEFORE YOU MOVE THE CONTROL LEVER. WITHOUT THE DOWNLOCKS, THE LANDING GEAR CAN RETRACT AND CAUSE INJURIES TO TO PERSONS AND DAMAGE TO EQUIPMENT.
 (1)  Make sure the downlocks are installed in the nose and main landing gear (AMM 32-00-20/201).
 S 485-030
 WARNING:_______OBEY THE INSTALLATION PROCEDURE FOR THE DOOR LOCKS. THE DOORS OPEN AND CLOSE QUICKLY. THE MOVEMENT OF THE DOORS CAN CAUSE INJURIES TO PERSONS AND DAMAGE TO EQUIPMENT.
 (2)  Open the doors for the landing gear and install the door locks (AMM 32-00-15/201).
 

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SEE B
SEE A
FWD
A
LANDING GEAR DOWN LINE
STABILIZING LINK
PRESSURE LINE TO TRUCK POSITIONER ACTUATOR
TRUCK POSITIONER
SHUTTLE VALVE

LANDING GEAR
UP LINE
FWD

LEFT TRUCK POSITIONER SHUTTLE VALVE
(RIGHT TRUCK POSITIONER SHUTTLE VALVE IS OPPOSITE)

B

Main Landing Gear Truck Positioner Shuttle Valve
Figure 501

M44806
 

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TRUCK POSITIONER ACTUATOR
SEE A
BLEED PLUG
PRESSURE PORT
FWD
FWD
LEFT GEAR OUTBOARD (RIGHT GEAR INBOARD IS EQUIVALENT)
A
TRUCK POSITIONER ACTUATOR
BLEED PLUG
RETURN PORT
FWD
LEFT GEAR INBOARD (RIGHT GEAR OUTBOARD IS EQUIVALENT)
A
Truck Positioner Actuator Figure 502
M44845
 

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 S 865-004
 (3)  
Open this circuit breaker on the overhead circuit breaker panel, P11, and attach a DO-NOT-CLOSE tag:

 (a)  
11G11, AUTO SPEEDBRAKE

 S 865-005
 (4)  
Remove the pressure from the left hydraulic system and hydraulic reservoir (AMM 29-11-00/201).

 D.
Do the Leak Check of the Shuttle Valve.

 S 865-031
 (1) Put the control lever for the landing gear in the OFF position.
 S 025-046
 WARNING:_______DO NOT LET HYDRAULIC FLUID GET ON YOU. PUT ON GOGGLES AND OTHER EQUIPMENT FOR PROTECTION. HYDRAULIC FLUID CAN CAUSE INJURIES TO PERSONS.
 CAUTION:_______DO NOT LET HYDRAULIC FLUID GET ON THE TIRES. IMMEDIATELY CLEAN THE TIRES IF HYDRAULIC FLUID GETS ON THEM. HYDRAULIC FLUID CAN CAUSE DAMAGE TO TIRES.
 (2)  
Disconnect the hydraulic RETURN line at the truck positioner actuator.

 S 425-033

 (3)  
Install a plug in the hydraulic line. Leave the port on the actuator open.

 S 025-034

 (4)  
Disconnect the UP line at the port on the truck positioner shuttle valve.

 S 425-035

 (5)  
Install a plug in the hydraulic line. Leave the port on the shuttle valve open.

 (6)
Move the control lever for the landing gear to the DN position.

 S 865-036
 

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 S 795-037
 (7)  Use the Alternating Current Motor Pumps (ACMP) to slowly increase the hydraulic pressure to 3000 psi. (a) If a leak occurs, remove the hydraulic pressure.
 S 215-038
 (8)  Look for leakage at the UP port on the truck positioner shuttle valve.
 (a) (b)  If leakage occurs at the UP port of the shuttle valve, the valve has internal leakage.Replace the shuttle valve (AMM 32-32-17/401).
 S 215-039
 (9)  Look for leakage at the RETURN port for the truck positioner actuator.
 (a) (b)  If leakage occurs at the RETURN port of the truck positioner actuator, the pressure relief valve in the actuator has internal leakage.Replace the truck positioner actuator (AMM 32-32-15/401).
 S 865-040

 (10)
 Put the control lever for the landing gear to the OFF position.
　
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