(a)
Make sure that Dimension B on the stabilizer ballscrew actuator is 15.89 | 0.01 inches (403.6 | 0.3 mm) (Fig. 502).
(b)
Remove the four PCA centering springs (Fig. 509) from the left and right elevators.
NOTE: Do not disconnect the centering spring support clips.
____ If the centering spring support clips are removed, the centering springs and PCA input cranks have to be adjusted.
WARNING: MANUALLY HOLD THE AFT QUADRANT OUTPUT CONTROL RODS
_______ WHEN THE RODS FROM THE AFT QUADRANTS ARE DISCONNECTED. THE ELEVATOR INPUT LINKAGES ARE SPRING LOADED. IF CONTROL RODS ARE NOT HELD, THEY CAN MOVE HARDOVER AND CAUSE INJURY TO PERSONS OR DAMAGE TO EQUIPMENT.
1) Manually hold the aft quadrant control rods.
2) Disconnect the output control rods for the left and right aft quadrant from the left and right aft quadrant output arms (Fig. 506).
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WARNING:_______ KEEP PERSONS AND EQUIPMENT AWAY FROM ALL CONTROL SURFACES
WHEN HYDRAULIC POWER IS SUPPLIED. AILERONS, ELEVATORS,
RUDDER, FLAPS, SLATS, SPOILERS, AND STABILIZER ARE FULLY
POWERED SURFACES. INJURY TO PERSONS OR DAMAGE TO
EQUIPMENT CAN OCCUR WHEN HYDRAULIC POWER IS SUPPLIED.
(c)
Pressurize the left hydraulic system (AMM 29-11-00/201).
(d)
Make sure that the right and center hydraulic systems are not pressurized (AMM 29-11-00/201).
CAUTION: USE ONLY LIGHT FINGER PRESSURE AND MOVE THE LINKAGE
_______ SLOWLY. THIS WILL PREVENT HIGH END LOADS IN THE ELEVATOR PCA ACTUATORS.
1) Push the left elevator linkage slowly outboard until a PCA touches bottom.
NOTE: A PCA touches bottom when a light force applied to
____ the elevator linkage will not move the elevator any further.
2) Measure and write down the elevator travel (Fig. 505). 3) Pull the left elevator linkage slowly inboard until a PCA
touches bottom. 4) Measure and write down the elevator travel (Fig. 505). 5) Do the same steps to measure and write down the right
elevator travel until a PCA touches bottom as was done for the left elevator.
6) Do the steps that follow to make sure that left elevator overtravel is correct: a) Compare the elevator full travel up with the PCA at
bottom against the three elevator full travel up measurements with each PCA supplied with power.
b) Make sure that the full travel up with PCA at bottom is at least 0.50 inch (12.7 mm) larger than any of the other three full travel up measurements.
NOTE: If the elevator overtravel is not correct,
____ do the procedure to adjust the elevator aft quadrant stops. After the stops are adjusted, do the steps to make sure that the elevator overtravel is correct again.
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c) Compare the elevator full travel down with the PCA at bottom against the three elevator full travel down measurements with each PCA supplied with power.
d) Make sure the full travel down with the PCA at bottom is at least 0.05 inch (1.3 mm) larger than the other three full travel down measurements.
NOTE: If the elevator overtravel is not correct,
____ do the procedure to adjust the elevator aft quadrant stops. After the stops are adjusted, do the steps to make sure that the elevator overtravel is correct again.
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