Removal Of Elevator Trim Assembly (Elevator); Installation Of Elevator Trim Assembly (Elevator); Removal Of Elevator Trim Sender Assembly - Piper Navajo Chieftain PA-31-350 Service Manual

NAVAJO CHIEFTAIN SERVICE MANUAL
5-33. REMOVAL OF ELEVATOR TRIM ASSEMBLY (Elevator). (Refer to Figure 5-6.)
a.
Remove the interior access panel to the aft section of the fuselage.
b.
Remove the access plates located on each side of the fuselage under the horizontal stabilizer; the
plate. under the rudder, on the top aft section of the fuselage; and the plate on the underside of the right
horizontal stabilizer.
c. Block the trim cables to prevent them from unwrapping at the screw assembly within the horizontal
stabilizer and within the fuselage at the bulkhead at station 244.00 by one of the methods shown in Figure 5-10.
(If the trim assembly within the fuselage is also to be removed, then block the cables at the trim screw assembly
in the control pedestal.)
d. Mark one set of cable ends within the fuselage at station 291.00 to facilitate installation and
disconnect the cables at the turnbuckles (12).
e. Remove the cable guard pin at station 352.00 through the access opening at the top aft section of
the fuselage.
f.
Disconnect the electrical leads from the sender unit (35).
g. Disconnect the trim control rod (20) from the trim screw (32).
h.
Remove the cap bolts (37) that attach the screw assembly (19) to the stabilizer spar.
i.
Remove the screw assembly and draw the trim cables from the fuselage and elevator.
5-34. INSTALLATION OF ELEVATOR TRIM ASSEMBLY (Elevator). (Refer to Figure 5-6.)
a. Ascertain that the trim cable assembly is evenly wrapped (centered) on the drum and the cables
are blocked to prevent them from unwrapping.
b. Allow the sender arm (34) to rotate freely on the sender shaft (36) until trim rigging and
adjustment is made.
c. Position the screw assembly with sender unit attached in the horizontal stabilizer, install the
attachment cap bolts (37) and secure. (Do not connect the fork of the trim screw (32) to the control rod
and arm assembly until trim rigging and adjustment is made.)
d.
Draw the trim cables through the stabilizer into the fuselage and connect them at the turnbuckles
(12) at station 291.00. (If the cables from the control pedestal are not installed, draw the cables tight and
block them at the bulkhead at fuselage station 317.75. Install the trim screw assembly in the control
pedestal.)
e. Remove the cable blocks from next to the trim screw assembly and from the cables leading from
the control pedestal.
f.
Connect the electrical leads to the sender unit.
g. Install the cable guard pin at fuselage station 352.00.
h. With the complete trim control system installed, set cable tension with turnbuckles (12) at station
291.00 per Table V-ll and check rigging and adjustment per paragraphs 5-37 and 5-38.
i. Install access plates and panels.
5-35. REMOVAL OF ELEVATOR TRIM SENDER ASSEMBLY. (Refer to Figure 5-6.)
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.
Revised: 5/3/84
SURFACE CONTROLS
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