Cessna 150M - Elevator Trim Control System

I
SECTION 9
ELEVATOR TRIM CONTROL SYSTEM
TABLE OF CONTENTS
ELEVATOR TRIM CONTROL SYSTEM.
Description
Trouble Shooting . . . . .
Trim Tab ....... .
Removal and Installation
Trim Tab Actuator . . . .
Removal and Installation
Disassembly. . . • • •
Cleaning, Inspection and Repair.
Reassembly. . . . . . . . . .
Page
9-1
9-1
9-1
9-2
9-2
9-2
9-2
9-2
9-4A
9-4A
Trim Tab Free-Play Inspection
Trim Tab Control Wheel
Removal and Installation
Cables and Pulleys . . . .
Removal and Installation
Rigging ........ .
9-4A I
9-6
9-6
9-6
9-6
9-6
9-1. ELEVATOR TRIM CONTROL SYSTEM. (Re-
fer to figure 9 -1. )
9-2. DESCRIPTION. The elevator trim tab, lo-
cated on the right elevator, is controlled by a trim
wheel mounted in the lower instrument panel. Pow-
er to operate the tab is transmitted from the trim
control wheel by means of chains, cables and an
actuator. A mechanical pointer, adjacent to the
trim wheel indicates tab position. A "nose-up"
setting results in a tab-down position.
9-3. TROUBLE SHOOTING.
NOTE
Due to remedy procedures in the following trouble shooting
chart it may be necessary to re-rig system, refer to para-
graph 9-12.
TROUBLE
PROBABLE CAUSE
REMEDY
TRIM CONTROL WHEEL MOVES
Cable tension too high.
Adjust tension.
WITH EXCESSIVE RESISTANCE.
Pulleys binding or rubbing.
Repair or replace as necessary.
Cables not in place on pulleys.
Install cables correctly.
Trim tab hinge binding.
Lubricate or replace hinge
as necessary.
Defective trim tab actuator.
Replace actuator.
Rusty chain.
Replace rusty chain.
Damaged sprocket.
Replace damaged sprockets.
Bent sprocket shaft.
Replace bent sprocket shafts.
Change 3 9-1