Installation Of Elevator Bellcrank Assembly; Rigging And Adjustment Of Elevator Controls - Piper Navajo Chieftain PA-31-350 Service Manual

NAVAJO CHIEFTAIN SERVICE MANUAL
5-27. INSTALLATION OF ELEVATOR BELLCRANK ASSEMBLY. (Refer to Figure 5-6.)
a. Position the bellcrank (14), install pivot bolt (24) and torque to 60-85 in. lbs.
b. Attach the forward end of the control rod (15) to the bellcrank (14) and secure.
NOTE
Apply corrosion retardant compound to the spring (16) with the
spring in the extended position. (Refer to the lubrication chart.)
c. The aft end of the control rod (15) and balance spring (16) are to be connected during rigging and
adjustment.
WARNING
Ensure that red end on balance cable is attached to red lug on
bellcrank
d. Connect the control cables (10 and 11 ) to the bellcrank (14). If color coded, ensure painted cable
end is connected to painted lug on bellcrank. Tighten bolts (22) so that the cable ends (21 ) may turn freely on
the bellcrank and safety.
e. Check cable tension per Fable V-ll and rigging and adjustment as given in paragraph 5-28. f. Install
access plates, tail cone and seat.
5-28. RIGGING AND ADJUSTMENT OF ELEVATOR CONTROLS. (Refer to Figure 5-6.)
a. Ensure that the left pilot's seat, the floor panel to the left of the control pedestal, an access plate on
the side of the fuselage under the horizontal stabilizer and tail cone are all removed.
b. Put the elevator in neutral position by placing a modified straight edge, as shown in Figure 5-7,
against the underside of the horizontal stabilizer, next to and inboard of the row of rivets at station 19.00 with
the aft end of the tool even with the trailing edge of the elevator. (This tool may be fabricated from dimensions
given in Figure 5-32.)
c. With the elevator in neutral position, check or adjust the elevator bellcrank ( 14) for neutral. The
bellcrank is neutral when the center of the forward attachment bolt (23) of the elevator control rod (15) is at
eight inches as measured perpendicular back from the bulkhead at station 317.75. Obtain this setting by turning
the control rod end (26) to the desired length and secure with jam nut (28).
d. With the elevator bellcrank neutral, adjust the turnbuckles (3) at fuselage station 110.50 to obtain
cable tension as given in Table V-II and correct tension to ambient temperature per Table V-I. Allow the control
wheel to neutralize fore and aft. The neutral position of the control wheel is 8.75 ± 0.25 inches as measured
from the instrument panel along the underside of the control column to the wheel.
e. To set the proper tension of the elevator balance spring ( 16), connect a spring scale to the aft end
of the spring and pull rearward until 37 Ibs. + 1 lb. tension is obtained with the elevator in the neutral position.
Observe which hole in the link (17) is in line with the hood at the end of the spring and connect the spring into
this hole in the link. If 37 Lbs. + 1 Lbs. cannot be reached with existing link holes, refer to latest revision of
Piper-Service Bulletins 549, and 626
NOTE
If provisions are provided for safety wiring the nut and screw on
the elevator hinge assembly, safety wire with MS209950 as
shown in Figure 5-8a. The lock wire should always be installed
and twisted so that the loop around the head stays down and
does not tend to come up over the bolt head and leave a slack
loop.
f. With the elevator neutral, place a bubble protractor on the inboard section of the elevator and
establish neutral or zero on the protractor. Move the elevator up until the control arm contacts its stop. (Refer
to Figure 5-8.) Check the up travel as given in Table V-ll. Adjust the stop screw in or out to obtain proper
adjustment. Move the elevator down and check and adjust by the same method. Tighten adjustment screw
locknuts and torque to 20-25 inch pounds. The elevator control arm should contact its stops before the control
wheel contacts its stops.
Revised: 3/31/94
SURFACE CONTROLS
1114