To Drain the Remaining Fuel from the Additional Center Tank (ACT)

TASK 28-25-00-650-005-A
To Drain the Remaining Fuel from the Additional Center Tank (ACT)

WARNING: OBEY THE FUEL SAFETY PROCEDURES.

WARNING: BE CAREFUL NOT TO GET AIRCRAFT FUEL IN YOUR MOUTH OR IN YOUR EYES. IF YOU GET FUEL ON YOUR SKIN OR ON YOUR CLOTHES, FLUSH IT IMMEDIATELY WITH WATER. IF NECESSARY, GET MEDICAL HELP. AIRCRAFT FUEL IS POISONOUS.

WARNING: DO NOT GET YOUR CLOTHES SOAKED WITH FUEL.

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.

WARNING: MAKE SURE THE AREA AROUND THE AIRCRAFT IS SAFE BEFORE YOU START THE REFUEL/DEFUEL PROCEDURE. IN THE SAFETY AREA, DO NOT:

SMOKE
MAKE SPARKS OR FIRE
USE ANY EQUIPMENT WHICH IS NOT APPROVED FOR REFUEL/DEFUEL PROCEDURES.

AIRCRAFT FUEL IS FLAMMABLE.

ZONE: 130
ZONE: 150
ZONE: 160

1. Reason for the Job
Self Explanatory

NOTE: If you do this procedure regularly it can prevent microbiological contamination of the fuel tanks.

2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE
No specific	2	ADAPTER 0,75 IN (19,05 MM) - SQUARE DRIVE
No specific	AR	CONTAINER 30 L(8 USGAL)
No specific	2	GAGE 5 BAR (75 PSI) - PRESSURE
No specific	1	GROUND PRESSURE GENERATOR - 0 TO 2 BAR (0 TO 30 PSI)
No specific	2	PROBE - NON METALLIC, FLEXIBLE
No specific	AR	SAFETY BARRIER(S)
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	2	STEPLADDER 0.5 M (1.6 FT)
No specific	AR	WARNING NOTICE(S)
98D28108293000	AR	ADAPTER-WATER DRAIN, ADDITIONAL CENTER TANK
98D28108293002	AR	ADAPTER-WATER DRAIN, ADDITIONAL CENTER TANK

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
130	FWD CARGO COMPT AFT BULKHEAD OF AVNCS COMPT TO FWD PRESSURE BULKHEAD OF WING CENTER BOX
150	AFT CARGO COMPARTMENT FWD PRESS BULKHEAD TO AFT BULKHEAD OF AFT CARGO COMPARTMENT
160	BULK CARGO COMPARTMENT AFT BULKHEAD OF AFT CARGO COMPARTMENT TO AFT BULKHEAD OF BULK CARGO COMPARTMENT
151NC, 153AZ, 192MB, 197AB, 197GB, 826
154AZ, 154BR, 198QB

C. Referenced Information

REFERENCE	DESIGNATION
TASK 24-41-00-861-002-A	Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01	Energize the Aircraft Electrical Circuits from the APU
TASK 24-41-00-861-002-A-02	Energize the Aircraft Electrical Circuits from Engine 1(2)
TASK 24-41-00-862-002-A	De-energize the Aircraft Electrical Circuits Supplied from the External Power
TASK 24-41-00-862-002-A-01	De-energize the Aircraft Electrical Circuits Supplied from the APU
TASK 24-41-00-862-002-A-02	De-energize the Aircraft Electrical Circuits Supplied from the Engine 1(2)
TASK 25-55-11-000-002-A	Removal of the Ceiling Panels in the Aft Cargo-Compartment - FR47/FR59
TASK 25-55-11-400-002-A	Installation of the Ceiling Panels in the Aft Cargo-Compartment - FR47/FR59
TASK 28-00-00-910-001-A	Fuel Safety Procedures
TASK 28-25-00-650-001-A	Pressure Defuel
TASK 52-30-00-860-001-A	Open the FWD or Aft Cargo-Compartment Door with the Yellow Electric Pump
TASK 52-30-00-860-002-A	Close the FWD or Aft Cargo-Compartment Door with the Yellow Electric Pump
TASK 53-35-13-000-001-A	Removal of the Belly Fairing Access Panels
TASK 53-35-13-400-001-A	Installation of the Belly Fairing Access Panels
Water Drain Adaptors
Water Drain Adaptor ** ON A/C NOT FOR ALL
Water Drain Adaptors ** ON A/C NOT FOR ALL
ACT Pressurization-Test Port T1/T2 ** ON A/C NOT FOR ALL

3. Job Set-up
Subtask 28-25-00-941-084-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) Obey the fuel safety procedures (Ref. AMM TASK 28-00-00-910-001).
(2) Put a WARNING NOTICE(S) on the panels that follow, to tell persons not to operate the refuel/defuel system:

Refuel/defuel control panels 800VU and 801VU
Fuel control panel 40VU.

(3) As necessary, use the applicable SAFETY BARRIERS, specified by the operator's instructions and your local regulations.

Subtask 28-25-00-860-069-A ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) Make sure that the ACT is defueled to its unusable fuel level (Ref. AMM TASK 28-25-00-650-001).
(2) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).
(3) Put a STEPLADDER 0.5 M (1.6 FT) below the applicable water drain valve.

Subtask 28-25-00-860-069-B ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) Make sure that the applicable ACT is defueled to its unusable fuel level (Ref. AMM TASK 28-25-00-650-001).
(2) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).
(3) Put a STEPLADDER 0.5 M (1.6 FT) below the applicable water drain valve.

Subtask 28-25-00-860-082-A ** ON A/C NOT FOR ALL

C. Aircraft Maintenance Configuration
(1) Make sure that each applicable ACT is defueled to its unusable fuel level (Ref. AMM TASK 28-25-00-650-001).
(2) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).
(3) Put a STEPLADDER 0.5 M (1.6 FT) below the applicable water drain valve.

Subtask 28-25-00-865-066-A ** ON A/C NOT FOR ALL

D. Open, safety and tag this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	ACT PUMP SUPPLY	25QH	Q29
** ON A/C NOT FOR ALL
121VU	FUEL/INLET VLV/MOT1/AFT 2	84QH	L29
121VU	FUEL/INLET VLV/MOT1/MAN SPLY/AFT 1	46QH	L28
121VU	FUEL/ACT/FUEL PUMP/SPLY	25QH	Q29

Subtask 28-25-00-010-092-A ** ON A/C NOT FOR ALL

E. Get Access (If ACT1 Installed)
(1) Remove the applicable access panels:

for the water drain-valve (174QM1), remove 198QB and 154AZ
for the water drain-valve (175QM1), remove 154BR.

NOTE: It is necessary to remove access panel 198QB to gain access to panel 154AZ.

Subtask 28-25-00-010-092-B ** ON A/C NOT FOR ALL

E. Get Access (If ACT1 and ACT2 Installed)
(1) Remove the applicable access panels:

for the water drain-valve (174QM1), remove 198QB and 154AZ
for the water drain-valve (175QM1), remove 154BR
for the water drain-valve (174QM2), remove 154DR
for the water drain-valve (175QM2), remove 153BR.

NOTE: It is necessary to remove access panel 198QB to gain access to panel 154AZ.

Subtask 28-25-00-010-087-F ** ON A/C NOT FOR ALL

F. Get Access
(1) Remove the applicable access panel(s):

For water drain-valve 226QM1, remove 197AB and 153AZ (Ref. AMM TASK 53-35-13-000-001)
For water drain-valve 226QM2, remove 197GB (Ref. AMM TASK 53-35-13-000-001).

Subtask 28-25-00-480-050-A ** ON A/C NOT FOR ALL

G. Installation of the Water Drain Adaptor

Water Drain Adaptors

Water Drain Adaptor ** ON A/C NOT FOR ALL

(1) Put a CONTAINER 30 L(8 USGAL) below the applicable water drain valve.
(2) Install the 98D28108293000 ADAPTER-WATER DRAIN, ADDITIONAL CENTER TANK or 98D28108293001 ADAPTER-WATER DRAIN, ADDITIONAL CENTER TANK as follows:
(a) Put the thrust rod (2) into the sleeve (1).
(b) Install the sleeve (1) in the water drain-valve tube.
(c) Hold the sleeve (1) and turn the nut (3) clockwise against the nut (4) to hold the water drain adaptor in position.

Subtask 28-25-00-480-050-C ** ON A/C NOT FOR ALL

G. Installation of the Water Drain Adapter

Water Drain Adaptors ** ON A/C NOT FOR ALL

(1) Put a CONTAINER 30 L(8 USGAL) below the applicable water drain valve.
(2) Install the 98D28108293000 ADAPTER-WATER DRAIN, ADDITIONAL CENTER TANK or 98D28108293002 ADAPTER-WATER DRAIN, ADDITIONAL CENTER TANK as follows:
(a) Put the thrust rod (2) into the sleeve (1).
(b) Install the sleeve (1) in the water drain-valve tube.
(c) Hold the sleeve (1) and turn the nut (3) clockwise against the nut (4) to hold the water drain adapter in position.

4. Procedure
Subtask 28-25-00-680-052-A ** ON A/C NOT FOR ALL

A. To Drain the Remaining Fuel

Water Drain Adaptors

Water Drain Adaptor ** ON A/C NOT FOR ALL

WARNING: DO NOT GET YOUR CLOTHES SOAKED WITH FUEL.

WARNING: BE CAREFUL WHEN YOU OPEN THE WATER DRAIN VALVES. SOME FUEL CAN ALSO COME OUT OF THE VALVES.

(1) Make sure that the container is in the correct position below the thrust rod (2).
(2) Use a non metallic probe to lift the thrust rod (2) against the water drain-valve. This causes the water drain-valve to open and the fuel to flow.
(3) Continue to hold the water drain-valve open until the fuel flow stops. Make sure that there is sufficient space in the container for all the drained fuel.

Subtask 28-25-00-680-053-A ** ON A/C NOT FOR ALL

B. To Drain the Remaining Fuel

Water Drain Adaptors ** ON A/C NOT FOR ALL

WARNING: BE CAREFUL WHEN YOU OPEN THE WATER DRAIN VALVES. SOME FUEL CAN ALSO COME OUT OF THE VALVES.

(1) Make sure that the container is in the correct position below the thrust rod (2).
(2) Use a PROBE - NON METALLIC, FLEXIBLE to lift the thrust rod (2) against the water drain valve. This causes the water drain valve to open and the fuel to flow.
(3) Continue to hold the water drain valve open until the fuel flow stops. Make sure that there is sufficient space in the container for all the drained fuel.

Subtask 28-25-00-680-051-D ** ON A/C NOT FOR ALL

C. To Fully Drain the ACT

ACT Pressurization-Test Port T1/T2 ** ON A/C NOT FOR ALL

(1) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(2) On the right side of the belly fairing, open quick-release access-door 192MB.
(3) On refuel/defuel control-panel 801VU, make sure that:
(a) All REFUEL VALVE switches are in the NORM and safe position.
(4) In the cockpit, on ACT-fuel control-panel 28VU:
(a) Make sure that the ACT XFR rotary switch is in the OFF position.
(b) Push the ACT XFR MODE SEL pushbutton switch (the MAN legend comes on and the ACT vent valve closes).

NOTE: The fuel inlet valve in each ACT will stay closed.

NOTE: The ACT FWD vent-isolation valve is permanently open.

(5) Put the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position at aft cargo-compartment-door 826.
(6) Open and safety aft cargo-compartment-door 826 (Ref. AMM TASK 52-30-00-860-001).
(7) Put the WARNING NOTICE(S) on the aft-cargo loading-system control-panel to tell persons not to operate the aft-cargo loading-system.
(8) In the aft cargo compartment:
(a) Set CARGO COMPT LIGHT switch 8LU to the ON position.
(b) Remove ceiling panel 151NC to get access to ACT-pressurization system-test ports T1 and T2 (Ref. AMM TASK 25-55-11-000-002).
(9) In the aft cargo compartment at test port T1:

Connect the ADAPTER 0,75 IN (19,05 MM) - SQUARE DRIVE
Connect the GAGE 5 BAR (75 PSI) - PRESSURE
Connect the GROUND PRESSURE GENERATOR - 0 TO 2 BAR (0 TO 30 PSI).

(10) Set the ground pressure generator to a maximum of 1 bar (14.50 psi).
(11) In the aft cargo compartment at test port T2:

Connect the ADAPTER 0,75 IN (19,05 MM) - SQUARE DRIVE
Connect the GAGE 5 BAR (75 PSI) - PRESSURE.

(12) Make sure that the CONTAINER 30 L(8 USGAL) is in the correct position below the thrust rod (2).

WARNING: DO NOT OPEN THE WATER DRAIN VALVE(S) WHEN THE TANK(S) IS/ARE PRESSURIZED. IF YOU DO, FUEL CAN COME OUT OF THE VALVE(S) WITH FORCE AND CAUSE YOU INJURY.

(13) Use the PROBE - NON METALLIC, FLEXIBLE to lift the thrust rod (2) against the water drain valve. This causes the water drain valve to open.
(14) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).
(15) Start the ground pressure generator.
(16) Let the ground pressure generator pressurize the ACT system.

NOTE: The ACT pressure reducing-valve decreases the pressure from 0 -0 bar or +1 bar (0 -0 psi or +14.50 psi) to 0.345 bar (5.00 psi).
The pressure in the ACT will increase and cause the remaining fuel to flow through the water drain valve.

(17) Make sure that the pressure on the pressure gage at test port T2 stays below 0.345 bar (5.00 psi). If the pressure increases above 0.345 bar (5.00 psi), stop the ground pressure generator immediately.
(18) Continue to hold the water drain valve in the open position until the fuel flow stops:
(a) Make sure that there is sufficient space in the CONTAINER 30 L(8 USGAL) for all the drained fuel.
(19) When the fuel flow from the water drain valve stops:

Stop the ground pressure generator
Carefully release the pressure at the ground pressure generator.

(20) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(21) At test port T1:
(a) Disconnect the ground pressure generator from the low pressure gage.
(b) Remove the low pressure gage and the ADAPTER 0,75 IN (19,05 MM) - SQUARE DRIVE.
(22) At test port T2, remove the low pressure gage and the ADAPTER 0,75 IN (19,05 MM) - SQUARE DRIVE.
(23) In the cockpit, on ACT fuel control-panel 28VU, release the ACT XFR MODE SEL pushbutton switch (the MAN legend goes off).

NOTE: The ACT vent valve opens and the pressure in the vent system releases.

(24) Install ceiling panel 151NC to close access to test ports T1 and T2 (Ref. AMM TASK 25-55-11-400-002).
(25) Set CARGO COMPT LIGHT switch 8LU to the OFF position.
(26) Close aft cargo-compartment-door 826 (Ref. AMM TASK 52-30-00-860-002).
(27) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).

Subtask 28-25-00-680-051-B

DELETED

Subtask 28-25-00-865-067-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	ACT PUMP SUPPLY	25QH	Q29
** ON A/C NOT FOR ALL
121VU	FUEL/INLET VLV/MOT1/AFT 2	84QH	L29
121VU	FUEL/INLET VLV/MOT1/MAN SPLY/AFT 1	46QH	L28
121VU	FUEL/ACT/FUEL PUMP/SPLY	25QH	Q29

5. Close-up
Subtask 28-25-00-080-050-A ** ON A/C NOT FOR ALL

A. Removal of the Water Drain Adaptor

Water Drain Adaptors

Water Drain Adaptor ** ON A/C NOT FOR ALL

Water Drain Adaptors ** ON A/C NOT FOR ALL

(1) When the fuel flow stops, remove the probe to close the water drain-valve.
(2) To release the water drain adaptor from the water drain valve tube:
(a) Hold the sleeve (1) and turn the nut (3) counter clockwise from the nut (4).
(3) Remove the thrust rod (2) from the sleeve (1).
(4) Examine the water drain valve for leakage. Leaks are not permitted.

Subtask 28-25-00-410-087-A ** ON A/C NOT FOR ALL

B. Close Access (ACT1 Installed)
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Install the applicable access panel:

for the water drain-valve (174QM1), install 154AZ and 198QB
for the water drain-valve (175QM1), install 154BR.

Subtask 28-25-00-410-087-B ** ON A/C NOT FOR ALL

B. Close Access (ACT1 and ACT2 Installed)
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Install the applicable access panel:

for the water drain-valve (174QM1), install 154AZ and 198QB
for the water drain-valve (175QM1), install 154BR
for the water drain-valve (174QM2), install 154DR
for the water drain-valve (175QM2), install 153BR.

Subtask 28-25-00-410-083-F ** ON A/C NOT FOR ALL

C. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Install the removed access panel(s):

For water drain-valve 226QM1, install 153AZ and 197AB (Ref. AMM TASK 53-35-13-400-001).
For water drain-valve 226QM2, install 197GB (Ref. AMM TASK 53-35-13-400-001).

Subtask 28-25-00-942-081-A ** ON A/C NOT FOR ALL

D. Removal of Equipment
(1) If installed, remove the safety barriers.
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).
(4) Remove the ground support and maintenance equipment, the special and standard tools and all other items.
(5) To discard the drained fuel, refer to your local regulations.

[Rev.10 from 2021] 2026.04.01 00:06:05 UTC