Mooney M20TN, Service And Maintenance Manual

Page: 183 / 1169

MOONEY AVIATION COMPANY, INC.
M20TN SERVICE & MAINTENANCE MANUAL
Page
Date
7
Rev Date
22--10--00 GARMIN GFC700 AUTOPILOT SERVOS
AND SERVO MOUNTS
The GSA 81 Servo is mated to the GSM 85 Servo
Mount to form a single servo unit. The design of the
servo assembly allows the servo portion to be re-
moved from the servo mount without the need to re--
rig the aircraft control cables. The M20TN aircraft is
equipped with 3 servos and servo mounts.
22--10--01 ROLL SERVO AND SERVO MOUNT
1. Removal of Roll Servo
A. Ensure aircraft power is off. Unplug any auxil-
iary power supplies.
B.
Remove the forward belly fairing.
C.
Set the ailerons in neutral position and insert
aileron rig pin.
D.
Remove the middle and side panels of the
center console to access roll servo.
ROLL SERVO MOUNTING
FIGURE 22--2
E.
Disconnect servo pigtail connector.
F. Remove the (2) mounting bolts from roll servo
to roll servo mount.
G. Remove the unit.
--CAUTION--
USE CARE WHEN REMOVING SERVO MOUNT
FROM AIRCRAFT NOT TO ALLOW ANY FOREIGN
OBJECT DEBRIS TO ENTER SERVO MOUNT ORI-
FICES (CLUTCH ASSY).
H.
Remove excess grease build--up from the
single servo output gear using a lint--free cloth.
NOTE:
It is not necessary to remove all of the grease
from the output gear, only the excess grease. DO
NOT USE SOLVENTS TO CLEAN THE OUTPUT
GEAR.
2. Removal of Roll Servo Mount
A.
Remove the center cotter pin and retaining
nut holding the roll servo mount arm.
B. Remove the safety wire (MS20995-C) and (6)
mounting screws and washers holding the roll servo
mount arm. Roll servo mount arm should be free to
remove.
C. Remove the (4) mounting bolts holding the
roll servo mount to the bracket. Remove servo
mount.
3. Roll Servo Mount Clutch Adjustment
A.
Prior to installation, adjust and verify the slip
clutch torque on the Roll Servo is set to 70
±
9 in. lbs.
Conduct a visual inspection and check slip clutches
once every 12 months. Refer to Section 22--10--04
Servo Clutch Adjustment Procedure.
4. Installation of Roll Servo and Roll Servo Mount
A.
Install roll servo mount (GSM85) to bracket
with original (4) bolts. Torque to 35
±
5 in. lbs.
B. Use a brush or applicator, apply a thin coat of
grease to the servo output gear. Use Aeroshell
33MS or Aeroshell 17. Clean and apply grease to
output gear every 1000 hours or 3 years.
C.
Install roll servo to roll servo mount with origi-
nal (2) bolts. Torque to 35
±
5 in. lbs. (see Figure
22--3)
D. With ailerons in neutral position install servo
mount arm with (6) mounting screws and washers.
Install center nut, washer and new cotter pin. Adjust
rod end on the servo control rod as needed (lengthen
or shorten) to obtain the proper 58
_
(
±
2
_
) alignment
(see Figure 22--3). Ensure control rod ends are prop-
erly engaged through witness holes in rod. Refer to
Chapter 27--10--00 for Aileron Rigging.
AUGUST 2010
22--10--00