Gsm 86 And Gsm 9100 Servo Gearbox; Gcu 477; Gmc 710 - Garmin G1000 Nxi System Maintenance Manual

GSM 86 and GSM 9100 Servo Gearbox

Removal:
1. Remove the desired servo motor(s) per Section 6.12.
2. For the Roll, Pitch and Yaw Servos: remove the servo bridle cables from the control
cable clamps. For the Pitch-Trim Servo: disconnect the servo cable at the forward
turnbuckle and aft terminal.
3. Use a socket or open-wrench to loosen and remove the servo attachment bolts.
4. Carefully remove the servo gearbox(es).
5. Remove the cable retention pins and ring (or cover) and then remove the servo cable
from the capstan.
Reinstallation:
1. Ensure cable retention pins are oriented correctly. Follow the installation instructions
provided in the respective servo installation drawing(s) listed in Table 1-1.
2. If no other maintenance is to be performed, reinstall the servo(s) per Section 6.12.

GCU 477

Removal:
1. Use a 3/32" hex drive tool to turn each of the four locking sockets ¼ turn
counterclockwise until they reach their stops.
2. Disconnect backshell assembly from unit.
Reinstallation:
1. Inspect connector(s) for damaged pins.
2. Connect backshell assembly to unit.
3. Hold unit flush with the pedestal, ensuring locking stud alignment marks are in the
vertical position.
4. Use a 3/32" hex drive tool to turn each of the four locking sockets ¼ turn clockwise. This
may require applying a small amount of forward pressure to engage the ¼ turn sockets.
5. Configure and test the GCU 477 according to Section 7.13.

GMC 710

Removal:
1. Use a 3/32" hex drive tool to turn each of the four locking sockets ¼ turn
counterclockwise until they reach their stops.
2. Disconnect backshell assembly from unit.
Reinstallation:
1. Inspect connector(s) for damaged pins.
2. Connect backshell assembly to unit.
3. Hold unit flush with the mounting bracket, ensuring locking stud alignment marks are in
the vertical position.
G1000 NXi System Maintenance Manual
King Air 300 Series
190-00716-N1
Page 238
Revision 1