Removal of the Magnetic Level-Indicator Lower-Housing

TASK 28-43-23-000-002-A
Removal of the Magnetic Level-Indicator Lower-Housing

WARNING: PUT THE SAFETY DEVICES AND THE WARNING NOTICES IN POSITION BEFORE YOU START A TASK ON OR NEAR:

THE FLIGHT CONTROLS
THE FLIGHT CONTROL SURFACES
THE LANDING GEAR AND THE RELATED DOORS
COMPONENTS THAT MOVE.

MOVEMENT OF COMPONENTS CAN KILL OR CAUSE INJURY TO PERSONS AND/OR CAN CAUSE DAMAGE TO THE EQUIPMENT.

FIN: 91QM

1. Reason for the Job
Self Explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	SAFETY BARRIER(S)
No specific	1	SCRAPER - PLASTIC
No specific	AR	WARNING NOTICE(S)

B. Referenced Information

REFERENCE	DESIGNATION
TASK 21-52-22-000-001-A	Removal of the Fan Plenum Chamber
TASK 28-00-00-910-001-A	Fuel Safety Procedures
TASK 28-43-23-000-001-A	Removal of the Magnetic Level-Indicator Rod
TASK 32-12-00-010-001-A	Open the Main Gear Doors for Access
Magnetic Level Indicator 91QM - Lower Assembly Detail ** ON A/C NOT FOR ALL
Magnetic Level Indicator 91QM - Lower Assembly Detail ** ON A/C NOT FOR ALL
Concession for 91QM ** ON A/C NOT FOR ALL
Magnetic Level Indicator 91QM - Lower Assembly Detail with Shim ** ON A/C NOT FOR ALL

3. Job Set-up
Subtask 28-43-23-941-058-A

A. Safety Precautions

WARNING: OBEY THE FUEL SAFETY PROCEDURES.

(1) You must obey the fuel safety procedures when you do work on the fuel system (Ref. AMM TASK 28-00-00-910-001).
(2) Put the SAFETY BARRIER(S) in position.
(3) Put a WARNING NOTICE(S) in position to tell persons not to operate the landing gear and the related doors.

Subtask 28-43-23-010-056-A

B. Get Access
(1) Open the main landing gear doors (Ref. AMM TASK 32-12-00-010-001).
(2) Make sure that the 460005835 SLEEVE - GROUND LOCK is on the applicable MLG door actuating-cylinder.
(3) Remove the left-hand plenum chamber, 10HM5 (Ref. AMM TASK 21-52-22-000-001).
(4) Remove the MLI rod from the MLI lower housing (Ref. AMM TASK 28-43-23-000-001).

4. Procedure
Subtask 28-43-23-020-058-A ** ON A/C NOT FOR ALL

A. Removal of the Magnetic Level-Indicator Lower-Housing 91QM
(1) If MLI lower housing part number 3508802-29 is installed, remove as follows:
(a) Remove the screw (3), the washer (4), the shim (5) and the bonding strap (2).

WARNING: USE PROTECTIVE GOGGLES AND GLOVES WHEN YOU REMOVE OR INSTALL LOCKWIRE. EACH TIME YOU CUT LOCKWIRE, REMOVE AND DISCARD IT IMMEDIATELY. LOOSE LOCKWIRE CAN CUT YOU OR MAKE YOU BLIND, AND/OR CAN CAUSE DAMAGE.

(b) Remove and discard the lockwire from the threaded bush (1).
(c) Remove the bolt (13), the washers (9) and (12) and the nut (8). Disconnect the bonding strap (11) from the bracket (10).
(d) Remove the threaded bush (1) from the center body.
(e) Remove the screws (6) and carefully remove the MLI lower housing (7) through the belly fairing skin. Do not cause damage to the bonding strap (11).
(2) If MLI lower housing part number FRH050001-2 is installed, remove as follows:
(a) Remove the screw (3), the washer (4), the shim (5) and the bonding strap (2).
(b) Remove the screws (6) and carefully remove the MLI lower housing (7) through the belly fairing skin.

Subtask 28-43-23-020-058-C ** ON A/C NOT FOR ALL

A. Removal of the Magnetic Level-Indicator Lower-Housing 91QM
(1) Remove the screw (3), the washer (4) and the bonding strap (2).
(2) Remove the screws (5) and carefully remove the MLI lower housing (1) through the belly fairing skin.

Subtask 28-43-23-020-058-D ** ON A/C NOT FOR ALL

A. Removal of the Magnetic Level-Indicator Lower-Housing 91QM

Concession for 91QM ** ON A/C NOT FOR ALL

(1) Remove the screw (3), the washer (4), the shim (5) and the bonding strap (2).

(2) Remove and discard the lockwire from the threaded bush (1).
(3) Remove the bolt (13), the washers (9) and (12) and the nut (8). Disconnect the bonding strap (11) from the bracket (10).
(4) Remove the threaded bush (1) from the center body.
(5) Remove the screws (6) and carefully remove the MLI lower housing (7) through the belly fairing skin. Do not cause damage to the bonding strap (11).
(6) Use a SCRAPER - PLASTIC to remove the shim (14) from the MLI lower housing (7).

Subtask 28-43-23-020-058-E ** ON A/C NOT FOR ALL

A. Removal of the Magnetic Level-Indicator Lower-Housing 91QM
(1) Remove the screw (3), the washer (4), the shim (5) and the bonding strap (2).
(2) Remove the screws (6) and carefully remove the MLI lower housing (7) through the belly fairing skin.
(3) Use SCRAPER - PLASTIC to remove shim(s) (8), if installed, from the MLI housing (7).
(4) Shim inspection;
(a) If shims(s) (8) are damaged measure the thickness and replace with new shim(s) (8) of the same dimension.
(b) If the shims (8) are serviceable keep for installation.

[Rev.10 from 2021] 2026.04.02 06:18:14 UTC