Removal
1. Remove power from the GSU 75H by pulling the ADAHRS circuit breaker.
2. Gain access to the GSU 75H.
3. Disconnect GSU 75H connector (J751).
4. Disconnect the pitot and static lines from the GSU 75H.
5. Loosen the two mounting screws on the connector end of the GSU 75H.
6. Lift the connector side of the GSU 75H and slide the unit towards the connector to remove from
the mounting rack.
Re-installation
1. Inspect the GSU 75H support shelf and ensure it is securely fastened to (existing) Center Beam
Y398.5 RH. Refer to Figure 6-10 for details.
2. Inspect GSU 75H mounting rack and ensure it is securely fastened to GSU 75H support shelf.
Ensure the shelf and remote rack are securely installed to the airframe.
3. Place the GSU 75H on the remote rack and slide the unit back until the feet are fully engaged with
the rack.
4. While pushing down on the unit, turn each retention screw clockwise. Torque screw 15 to
20 in-lbf.
5. Inspect the connector and pins for signs of damage. Repair any damage.
6. Inspect the pitot and static lines and ports for signs of damage. Repair any damage.
7. Connect pitot and static lines. Refer to Figure 6-11 for details.
8. Connect the GSU 75H connector (J751).
9. Configure and checkout the GSU 75H following procedures detailed in Figure 7.4.
190-02081-03
Rev. 3
GFC 600H HFCS Part 27 STC Maintenance Manual
Page 6-20