Removal Of Elevator Trim Sender Assembly; Installation Of Elevator Trim Sender Assembly; Rigging And Adjustment Of Elevator Trim - Piper Navajo PA-31 Service Manual

PIPER NAVAJO SERVICE MANUAL
5-33. REMOVAL OF ELEVATOR TRIM SENDER ASSEMBLY. (Refer to Figure 5-5.)
a. Remove access plate located on underside of right horizontal stabilizer.
b. Disconnect the electrical leads to the sender.
c. Loosen the bolt that secures the sender arm (34) on the sender shaft (36).
d. Loosen and turn off nut (42) that attaches sender unit (35) to mounting bracket (39).
e. Slide the sender from the mounting bracket and the sender arm.
f. Remove the sender through the access opening.
g. The sender arm may be removed from the trim screw, if desired.
5-34. INSTALLATION OF ELEVATOR TRIM SENDER ASSEMBLY. (Refer to Figure 5-5.)
a. If removed, install the sender arm (34) on the trim screw (32).
b. Insert the shaft (36) of sender unit (35) through mounting bracket (39), lock washer (43),
locknut (42) and sender arm.
c. Position sender unit on its mounting bracket by placing the index tab on the sender into the
index slot in the bracket. Secure sender on the mounting bracket. (Allow the arm to rotate freely on the
sender shaft until adjustment is made.)
d. Connect the electrical leads to the sender.
e. Rig the sender unit per Paragraph 5-36.
f. Install access plate.
5-35. RIGGING AND ADJUSTMENT OF ELEVATOR TRIM. (Refer to Figure 5-5.)
PPS-50046F
a. To adjust the elevator trim, it must be ascertained that the following has been accomplished
either during installation or as a preadjustment check:
1. On serial nos. 31-5 to 31-711 inclusive, trim cables are evenly wrapped (centered) on their
drums, both in the control pedestal and in the horizontal stabilizer, and both cable turnbuckles (12) are
located approximately at fuselage station 308.0.
2. For serial nos. 31-712 and up, trim cables are evenly wrapped (centered) on their drum in
the control pedestal. The drum located in the horizontal stabilizer has 18-1/2 turns on the drum with 6
turns on the drum end towards the clevis end of the screw and cable ends opposite each other. Both cable
turnbuckles (12) are located approximately at fuselage station 291.0.
NOTE
If the AltiMatic V Flight Director is installed, check to determine
that the trim cable is wrapped around the capstan of the elevator
trim servo as illusted in Figure 5-8a. The trim servo is located at
fuselage station 317.75.
3. Cable tension is set as given in Table V-I.
b. Remove the access plate on the underside of the right horizontal stabilizer.
c. Rotate the trim drum until 5 (6, serial nos. 31-712 and up) wraps exist on the drum at the aft
(base end) series of cable wraps. (The drum is neutral in this position.)
Revised: 3/2/84
SURFACE CONTROLS
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