Removal of the Water Drain Valve

TASK 28-11-41-000-003-A
Removal of the Water Drain Valve

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.

ZONE: 540
ZONE: 640
FIN: 25QM
FIN: 26QM

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	ACCESS PLATFORM 3M (10 FT)
No specific	1	ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE
No specific	AR	CAP - BLANKING
No specific	AR	SAFETY BARRIER(S)
98D57004014000	1	HOOK-COVER (RIB2-SURGE DOORS)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
540	FUEL TANK
640	FUEL TANK
540AB, 540BZ, 640AB, 640BZ

C. Referenced Information

REFERENCE	DESIGNATION
TASK 28-10-00-910-001-A	Safety Procedures When You Do Work in a Fuel Tank
TASK 28-10-00-910-002-A	Access to the Fuel Tanks and the Work Areas
TASK 28-25-00-650-001-A	Pressure Defuel
TASK 28-25-00-650-003-A	To Drain Remaining Fuel from the Wing Tanks and the Center Tank
TASK 28-25-00-650-003-A-01	To Drain Remaining Fuel from the Wing Tanks and the Center Tank
TASK 33-42-11-000-001-A	Removal of the Landing Light
TASK 57-27-11-000-001-A	Removal of the Access Panel
TASK 57-27-12-000-002-A	Removal of the Rib 2 Access Panel 540AZ(640AZ) or 540BZ(640BZ)
Water Drain Valve - Inner Cell ** ON A/C NOT FOR ALL
Water Drain Valve - Wing Tank ** ON A/C NOT FOR ALL

3. Job Set-up
Subtask 28-11-41-941-069-A

A. Safety Precautions

WARNING: BEFORE YOU DO WORK IN OR NEAR A FUEL TANK, MAKE SURE THAT YOU OBEY ALL THE SAFETY PROCEDURES. THIS WILL PREVENT INJURY TO PERSONS AND/OR DAMAGE TO THE AIRCRAFT.

(1) You must obey the safety procedures when you do work in a fuel tank (Ref. AMM TASK 28-10-00-910-001).
(2) As necessary, use the applicable SAFETY BARRIERS, specified by the operator's instructions and your local regulations.

Subtask 28-11-41-650-072-A

B. Fuel Configuration
(1) Defuel the applicable wing tank (Ref. AMM TASK 28-25-00-650-001).
(2) Drain the fuel that remains from the applicable wing tank inner cell (Ref. AMM TASK 28-25-00-650-003).

Subtask 28-11-41-010-054-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Put the ACCESS PLATFORM 3M (10 FT) in position below the applicable access panel 540AB 640AB.
(2) Remove the applicable access panel 540AB 640AB (Ref. AMM TASK 57-27-11-000-001) and (Ref. AMM TASK 28-10-00-910-002).
(3) Open the applicable wing tank surge door 540BZ 640BZ.
(4) Install the 98D57004014000 HOOK-COVER (RIB2-SURGE DOORS) on the applicable wing tank surge door.

Subtask 28-11-41-010-054-B ** ON A/C NOT FOR ALL

C. Get Access
(1) Put the ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE in position below the applicable access panel 540AB ( 640AB).
(2) Remove the applicable access panel 540AB ( 640AB) (Ref. AMM TASK 57-27-11-000-001) and (Ref. AMM TASK 28-10-00-910-002).
(3) Remove the applicable rib 2 access panel 540BZ ( 640BZ) (Ref. AMM TASK 57-27-12-000-002).

4. Procedure
Subtask 28-11-41-020-052-C ** ON A/C NOT FOR ALL

A. Removal of the Water Drain Valve
(1) Remove the nut (2) from the union (3).
(2) Carefully move the pipe (1) a small distance away (to let you remove the water drain valve (5)). Seal the end of the pipe with a CAP - BLANKING.
(3) Remove the nuts (6), the bolts (8) and disconnect the bonding lead (10).
(4) Remove the water drain valve (5).
(5) Remove and discard the O-rings (7) and (9).
(6) Remove the union (3) from the water drain valve (5).
(7) Remove and discard the O-ring (4).
(8) Examine the water drain valve (5) and the adjacent aircraft structure for signs of fuel leakage.
(9) If signs of fuel leakage are found, examine the applicable landing light assembly for fuel contamination (Ref. AMM TASK 33-42-11-000-001).

Subtask 28-11-41-020-052-F ** ON A/C NOT FOR ALL

[Rev.10 from 2021] 2026.04.01 00:01:26 UTC