Installation of the Main-Transfer-System Clack Valve

TASK 28-26-44-400-001-A
Installation of the Main-Transfer-System Clack Valve

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

WARNING: MAKE SURE THAT THE FLIGHT CONTROL SAFETY-LOCKS AND THE WARNING NOTICES ARE IN POSITION.

WARNING: MAKE SURE THAT THE GROUND SAFETY-LOCKS ARE IN POSITION ON THE LANDING GEAR. THIS WILL PREVENT UNWANTED MOVEMENT OF THE LANDING GEAR, AND THUS POSSIBLE INJURY TO PERSONS AND DAMAGE TO THE AIRCRAFT AND/OR EQUIPMENT.

ZONE: 540
ZONE: 640

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	AR	WARNING NOTICE(S)
98D57004014000	1	HOOK-COVER (RIB2-SURGE DOORS)

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.01ABA1)	Turbine Fuel-- Kerosene -
(Material No.03FAB1)	Mineral Oil base Grease-- Vaseline or Petrolatum -
(Material No.06ABA1)	Polysulfide Sealant-Fuel Tank Brushable -
(Material No.08BAA9)	Non Aqueous Cleaner-General - -
(Material No.14SBA1)	Textile-Lint free Cotton -

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
540	FUEL TANK
640	FUEL TANK
148AZ, 540AB, 540BZ, 640AB, 640BZ, 734, 744
147AZ

D. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
29	O-RING	AIPC 28-26-05-04-120
4	O-RING	AIPC 28-26-05-04-120
7	O-RING	AIPC 28-26-05-04-240
10	O-RING	AIPC 28-26-44-01-120
29	O-RING	AIPC 28-26-85-04-110
4	O-RING	AIPC 28-26-85-04-110
7	O-RING	AIPC 28-26-85-04-230

E. Referenced Information

REFERENCE	DESIGNATION
TASK 12-11-28-650-003-A	Pressure Refuel with Automatic Control
TASK 20-28-00-912-802-A	Electrical Bonding - General Maintenance Procedure
TASK 28-00-00-000-001-A	Removal of the Fuel Pipes
TASK 28-00-00-400-001-A	Installation of the Fuel Pipes
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 28-25-00-869-001-A	Fuel Transfer
TASK 28-26-00-710-001-A	Operational Test of the Main Transfer System
TASK 28-42-15-000-005-A	Removal of the Wing-Tank Fuel-Quantity Probes
TASK 28-42-15-400-005-A	Installation of the Wing-Tank Fuel-Quantity Probes
TASK 32-12-00-010-001-A	Open the Main Gear Doors for Access
TASK 32-12-00-410-001-A	Close the Main Gear Doors after Access
TASK 57-17-11-000-001-A	Removal of Access Cover 147AZ(148AZ)
TASK 57-17-11-000-001-B	Removal of Access Cover 148AZ or/and the ACT-Equipment Support Door
TASK 57-17-11-400-001-A	Installation of Access Cover 147AZ(148AZ)
TASK 57-17-11-400-001-B	Installation of Access Cover 148AZ or/and the ACT-Equipment Support-Door
TASK 57-27-11-000-001-A	Removal of the Access Panel
TASK 57-27-11-400-001-A	Installation of the Access Panel
Main-Transfer-System Clack Valve - Location and Detail

3. Job Set-up
Subtask 28-26-44-941-052-A ** ON A/C NOT FOR ALL

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 fuel safety procedures (Ref. AMM TASK 28-10-00-910-001) when you do work in a fuel tank.
(2) Make sure that the SAFETY BARRIER(S) are in position.
(3) Make sure that the WARNING NOTICE(S) is in position to tell persons not to operate the landing gear doors.

Subtask 28-26-44-860-050-A ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) Make sure that the applicable fuel tank is defueled (Ref. AMM TASK 28-25-00-650-001).
(2) Make sure that the remaining fuel has been drained from the applicable fuel tank (Ref. AMM TASK 28-25-00-650-003).
(3) Make sure that the applicable MLG doors 734 (744) are open (Ref. AMM TASK 32-12-00-010-001).
(4) Make sure that the 460005835 SLEEVE - GROUND LOCK is on the applicable MLG door actuating cylinder.
(5) Make sure that the access platform is below the applicable access panel(s) 147AZ (148AZ), 540AB (640AB).
(6) Make sure that the applicable access panels 147AZ (148AZ), 540AB (640AB) are removed (Ref. AMM TASK 28-10-00-910-002), (Ref. AMM TASK 57-17-11-000-001), (Ref. AMM TASK 57-27-11-000-001).
(7) Make sure that the applicable spring-loaded surge-doors 540BZ (640BZ) are open and safetied with the 98D57004014000 HOOK-COVER (RIB2-SURGE DOORS).
(8) Make sure that the applicable Fuel Quantity Indicating (FQI) probes have been removed (Ref. AMM TASK 28-42-15-000-005).
(9) Make sure that the applicable fuel pipes have been removed (Ref. AMM TASK 28-00-00-000-001).

Subtask 28-26-44-860-050-B ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) Make sure that the applicable fuel tank is defueled (Ref. AMM TASK 28-25-00-650-001).
(2) Make sure that the remaining fuel has been drained from the applicable fuel tank (Ref. AMM TASK 28-25-00-650-003).
(3) Make sure that the applicable MLG doors 734 (744) are open (Ref. AMM TASK 32-12-00-010-001).
(4) Make sure that the 460005835 SLEEVE - GROUND LOCK is on the applicable MLG door actuating cylinder.
(5) Make sure that the access platform is below the applicable access panel(s) 147AZ (148AZ), 540AB (640AB).
(6) Make sure that the applicable access panels 148AZ, 540AB (640AB) are removed (Ref. AMM TASK 28-10-00-910-002), (Ref. AMM TASK 57-17-11-000-001), (Ref. AMM TASK 57-27-11-000-001).
(7) Make sure that the applicable spring-loaded surge-doors 540BZ (640BZ) are open and safetied with the 98D57004014000 HOOK-COVER (RIB2-SURGE DOORS).
(8) Make sure that the applicable Fuel Quantity Indicating (FQI) probes have been removed (Ref. AMM TASK 28-42-15-000-005).
(9) Make sure that the applicable fuel pipes have been removed (Ref. AMM TASK 28-00-00-000-001).

Subtask 28-26-44-865-051-A ** ON A/C NOT FOR ALL

C. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	FUEL/L WING TK/PUMP2 SPLY	7QA	N26
121VU	FUEL/L WING TK/PUMP1 SPLY	1QA	N23
121VU	FUEL/R WING TK/PUMP2 SPLY	8QA	Q26
121VU	FUEL/R WING TK/PUMP1 SPLY	2QA	Q23
121VU	FUEL/CTR TK/AUTO/CTL	3QL	R27
121VU	FUEL/CTR TK/L&R XFR/CTL & IND	2QL	R26
121VU	FUEL/CTR TK/L&R XFR/CTL & IND	1QL	R25
123VU	L WING TK/PUMP 1/STBY SPLY	11QA	AD12
123VU	R WING TK/PUMP 1/STBY SPLY	12QA	AE12

4. Procedure
Subtask 28-26-44-420-051-A ** ON A/C NOT FOR ALL

A. Preparation for Installation
(1) Clean the component interface and/or the adjacent area with a Textile-Lint free Cotton - (Material No.14SBA1) made moist with Non Aqueous Cleaner-General - - (Material No.08BAA9) .
(2) Make sure that the parts retained from the removed component are clean and in the correct condition.
(3) Do an inspection of the component interfaces and the adjacent area.
(4) Lubricate the new items that follow with Turbine Fuel-- Kerosene - (Material No.01ABA1) or Mineral Oil base Grease-- Vaseline or Petrolatum - (Material No.03FAB1) :

Subtask 28-26-44-420-050-A ** ON A/C NOT FOR ALL

B. Installation of the Main-Transfer-System Clack Valve
(1) Install the new O-rings (4) and (29) on the flanged pipe (30).
(2) Install the new O-ring (10) on the seating (11).
(3) Install the new O-ring (7) on the adaptor (24).
(4) Install the flanged pipe (30) through the hole in RIB 1.
(5) Install the nut (2) and the split ring (3) on the flanged pipe (30).
(6) Remove the blanking cap from the pipe (1).
(7) Put the flanged pipe (30) in position on the pipe (1).
(8) Loosely engage the nut (2) on the pipe (1).
(9) Install the washers (6) on the bolts (5).
(10) Put the adaptor (24) in position on the flanged pipe (30).
(11) Install the bolts (5), the washers (8) and the nuts (9).
(12) Tighten the nut (2).
(13) Put the seating (11) in position on the adaptor (24).
(14) Install the bolts (26), the washers (23) and the nuts (22).
(15) Seal the bolts (26) and the nuts (22) with Polysulfide Sealant-Fuel Tank Brushable - (Material No.06ABA1) .
(16) Put the clack valve assembly (13) and the distance tubes (14) and (21) in position on the seating (11).
(17) Install the spindle (12).
(18) Carefully put the shroud assembly (16) in position on the adaptor (24). Adjust the position of the spindle (12), as necessary, so that you can put the shroud assembly (16) in position.
(19) Install the bolts (25) and the nuts (20).
(20) Install the washer (27) on the bolt (28). Install the bolt (28), the washer (19), the bonding strap (15), the washer (18) and the nut (17) (Ref. AMM TASK 20-28-00-912-802).
(21) Seal these items with Polysulfide Sealant-Fuel Tank Brushable - (Material No.06ABA1) :

the nuts (9) and (20)
the bolts (5) and (25).

(22) Make sure that the clack valve assembly (13) and the spindle (12) are free to move in the seating (11).
(23) Make sure that the clack valve assembly (13) is flat against the seating (11) when closed.

Subtask 28-26-44-410-050-A ** ON A/C NOT FOR ALL

C. Close Access
(1) Install the fuel pipes that you removed (Ref. AMM TASK 28-00-00-400-001).
(2) If necessary, install the applicable Fuel Quantity Indicating (FQI) probe (Ref. AMM TASK 28-42-15-400-005):

for the LH wing, install the FQI probe 54QT1

for the RH wing, install the FQI probe 54QT2.

(3) Make sure that the work area is clean and clear of tools and other items.
(4) Make sure that all of the bonding straps are correctly installed and attached (Ref. AMM TASK 20-28-00-912-802), before you install the fuel-tank access panels.
(5) Remove the 98D57004014000 HOOK-COVER (RIB2-SURGE DOORS) from the applicable spring-loaded surge-door and carefully close:

for the LH wing, the door 540BZ

for the RH wing, the door 640BZ.

(6) Install the applicable access panels (Ref. AMM TASK 57-27-11-400-001) (Ref. AMM TASK 57-17-11-400-001):

for the LH wing, install the panels 540AB 147AZ

for the RH wing, install the panels 640AB 148AZ.

(7) Remove the access platform(s).
(8) Close the applicable MLG door(s) (Ref. AMM TASK 32-12-00-410-001):

for the LH wing, close the door 734

for the RH wing, close the door 744.

Subtask 28-26-44-410-050-B ** ON A/C NOT FOR ALL

for the LH wing, install the FQI probe 54QT1

for the RH wing, install the FQI probe 54QT2.

for the LH wing, the door 540BZ

for the RH wing, the door 640BZ.

(6) Install the applicable access panels (Ref. AMM TASK 57-27-11-400-001) (Ref. AMM TASK 57-17-11-400-001):

for the LH wing, install the panel 540AB

for the RH wing, install the panels 640AB 148AZ.

(7) Remove the access platform(s).
(8) Close the applicable MLG door(s) (Ref. AMM TASK 32-12-00-410-001):

for the LH wing, close the door 734

for the RH wing, close the door 744.

Subtask 28-26-44-865-052-A ** ON A/C NOT FOR ALL

D. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	FUEL/L WING TK/PUMP2 SPLY	7QA	N26
121VU	FUEL/L WING TK/PUMP1 SPLY	1QA	N23
121VU	FUEL/R WING TK/PUMP2 SPLY	8QA	Q26
121VU	FUEL/R WING TK/PUMP1 SPLY	2QA	Q23
121VU	FUEL/CTR TK/AUTO/CTL	3QL	R27
121VU	FUEL/CTR TK/L&R XFR/CTL & IND	2QL	R26
121VU	FUEL/CTR TK/L&R XFR/CTL & IND	1QL	R25
123VU	L WING TK/PUMP 1/STBY SPLY	11QA	AD12
123VU	R WING TK/PUMP 1/STBY SPLY	12QA	AE12

Subtask 28-26-44-710-050-A ** ON A/C NOT FOR ALL

E. Test
(1) Do an operational test of the main transfer system (Ref. AMM TASK 28-26-00-710-001).

5. Close-up
Subtask 28-26-44-650-051-A ** ON A/C NOT FOR ALL

A. Fuel Configuration
(1) Refuel, defuel or transfer fuel as necessary (Ref. AMM TASK 12-11-28-650-003), (Ref. AMM TASK 28-25-00-650-001) or (Ref. AMM TASK 28-25-00-869-001).

Subtask 28-26-44-942-050-A ** ON A/C NOT FOR ALL

B. Removal of Equipment
(1) Remove the safety barriers.
(2) Remove the WARNING NOTICE(S).
(3) Remove the ground support and maintenance equipment, the special and standard tools and all other items.

[Rev.10 from 2021] 2026.04.02 07:03:22 UTC