CESSNA®
MODEL 525 (SERIALS -0685 AND -0800 AND ON)
MAINTENANCE MANUAL
7.
Elevator Trim Tab Actuator Removal/Installation
A.
Remove the Trim Tab Actuator. (Refer to Figure 404).
(1) Disengage the PITCH TRIM circuit breaker on the left circuit breaker panel in the cockpit.
(2) Gain access to the trim tab actuator and the turnbuckle by removing panels 321CTC and 331AB
(right) or 332AB (left). Refer to Chapter 6, Access Plates and Panels Identiication - Description
and Operation.
(3) Find the trim actuator that will be removed.
(a) Used an approved clamp to temporarily hold the opposite elevator in the streamlined
position.
(b) Use the pitch trim wheel in the cockpit to manually move the elevator trim tab until it is lush
with the elevator.
(c) Install an inclinometer on the opposite elevator and the elevator trim tab.
1
Zero the inclinometers.
(d) Use the pitch trim wheel in the cockpit to manually move the elevator trim tabs 4 degrees
(+1 or -1 degree) down from the streamlined position.
1
Use tape to hold the trim tab to the elevator.
(4) Remove the clamp from the elevator.
(5) Measure and record the distance from the rod end bearings to the actuator face plate.
CAUTION:
Make sure that the trim pushrods do not catch on the adjacent
structure when they are disconnected from the trim actuators.
Damage to the structure can occur if the elevator tab is moved
when the pushrods are disconnected.
(6) Carefully lift the elevators with your hands to get access to the elevator trim actuator pushrods.
(7) Remove the cotter pins, nuts, washers and bolts that attach the elevator trim actuator push rods
to trim tab actuator.
(a) Disconnect the pushrods from the actuator.
(b) Put a #10 bolt through the trim actuator rod end bearings to keep them in the correct
alignment.
(8) Remove the elevator to get access to the elevator trim actuator. Refer to Chapter 55, Elevator -
(9) Loosen the elevator trim and the elevator electric trim cable turnbuckles.
(10) Remove the screw and the spacer from the trim tab actuator chain guard.
(11) Remove/lift the trim tab actuator chain from the trim tab actuator sprocket.
(12) Remove the bolts securing the actuator to the horizontal stabilizer.
(13) Remove the actuator from the airplane.
B.
Install the Trim Tab Actuator (Refer to Figure 404.).
(1) If a new elevator trim tab actuator is installed, do the steps that follow:
(a) Install a #10 bolt between both rod end bearings to keep their alignment.
(b) Turn the drive sprocket to put the rod end bearings at the recorded distance from the
actuator face plate.
(2) If the initial elevator trim tab actuator is installed, do the steps that follow:
(a) Lubricate elevator trim tab actuator with 5565450-28 grease. Refer to Chapter 12, Flight
(b) Use the drive sprocket to fully extend and retract the trim tab actuator between four and
six times.
(c) Turn the drive sprocket to put the rod end bearings back to the recorded distance from the
actuator face plate.
(3) Put the trim tab actuator in its position at the horizontal stabilizer.
(4) Install the trim tab actuator chain over the trim tab actuator sprocket.
NOTE:
Install chain(s) on actuator sprocket(s) as shown in Figure 404, with eye of actuator
pushrod aligned with the elevator bearings. Cable assembly/chain interface should
be even (top and bottom) when the elevator trim system is properly rigged and
placed in its neutral position of 4 degrees down.
27-30-10
Page 410
© TEXTRON AVIATION INC.
Nov 22/2017
ICA-525-27-00005
Form 2261 Rev 1
