Check Distribution Piping to Detect Leakage and Obstruction

TASK 26-21-00-720-003-C
Check Distribution Piping to Detect Leakage and Obstruction

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

ZONE: 415
ZONE: 425

1. Reason for the Job
Refer to the MPD TASK: 262100-04
CHECK DISTRIBUTION PIPING TO DETECT LEAKAGE AND OBSTRUCTION.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	2	ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE
No specific	1	AIR SOURCE 2 BAR (30 PSI) - REGULATED, FILTERED, DRY
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)
No specific	Torque wrench: range to between 0.495 and 0.405 m.daN (43.81 and 35.84 lbf.in )
98D26203001000	1	TEST TOOL-ENG. FIRE EXTINGUISHING SYST.(IAEV2500)

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.14CCB6)	Testing Medium-Leak Detection - Oxygen System
(Material No.14SBA1)	Textile-Lint free Cotton -

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
415	LOWER PYLON
425	LOWER PYLON
415BL, 415BR, 425BL, 425BR
FOR [1000EM1] (ENGINE-1)
437AL, 438AR, 451AL, 452AR
FOR [1000EM2] (ENGINE-2)
447AL, 448AR, 461AL, 462AR

D. Referenced Information

REFERENCE	DESIGNATION
TASK 26-21-41-400-001-A	Installation of the Engine Fire-Extinguisher Bottle
TASK 71-13-00-010-010-A	Opening of the Fan Cowls 437AL(447AL),438AR(448AR)
TASK 71-13-00-410-010-A	Closing of the Fan Cowls 437AL(447AL),438AR(448AR)
TASK 78-30-00-040-012-A	Deactivation of the Thrust Reverser Hydraulic Control Unit (HCU) for Ground Maintenance
TASK 78-30-00-440-012-A	Re-activation of the Thrust Reverser Hydraulic Control Unit (HCU) after Ground Maintenance
TASK 78-32-00-010-010-A	Opening of the Thrust Reverser Halves
TASK 78-32-00-410-010-A	Closing of the Thrust Reverser Halves
Distribution Line
Vibration Harness

3. Job Set-up
Subtask 26-21-00-865-069-A ** ON A/C NOT FOR ALL

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/B	2WE1	Q44
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/A	1WE1	Q43
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/B	2WE2	Q42
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/A	1WE2	Q41

Subtask 26-21-00-860-051-A ** ON A/C NOT FOR ALL

B. Safety Precautions
(1) On the center pedestal, on the ENG panel 115VU:
(a) Make sure that the ENG/MODE/CRANK/NORM/IGN/START selector switch is in the NORM position.
(b) Put a WARNING NOTICE(S) to tell persons not to start the engine.
(2) Make sure that the engine 1(2) shutdown occurred not less than 5 minutes before you do this procedure.
(3) On the overhead maintenance panel 50VU:
(a) Make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) to tell persons not to energize the FADEC 1(2).

Subtask 26-21-00-010-062-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Open the fan cowls (Ref. AMM TASK 71-13-00-010-010):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR.
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR.
(2) Put the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position.

Subtask 26-21-00-040-052-A ** ON A/C NOT FOR ALL

D. Deactivate the Thrust Reverser HCU

WARNING: MAKE SURE THAT THE THRUST REVERSER HYDRAULIC CONTROL UNIT (HCU) IS DEACTIVATED BEFORE YOU DO WORK ON OR AROUND THE THRUST REVERSER. IF THE HCU IS NOT DEACTIVATED, THERE IS A RISK OF UNWANTED THRUST REVERSER OPERATION WHICH CAN CAUSE INJURY TO PERSONS AND/OR DAMAGE TO EQUIPMENT.

(1) Deactivate the thrust reverser Hydraulic Control Unit (HCU) (Ref. AMM TASK 78-30-00-040-012).

Subtask 26-21-00-010-063-A ** ON A/C NOT FOR ALL

E. Get Access
(1) Open the thrust reverser halves (Ref. AMM TASK 78-32-00-010-010):
(a) FOR [1000EM1] (ENGINE-1)
451AL, 452AR.
(b) FOR [1000EM2] (ENGINE-2)
461AL, 462AR.
(2) Put the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position.
(3) On the left engine pylon, remove the access doors:
415BL 415BR.
(4) On the right engine pylon, remove the access doors:
425BL 425BR.

4. Procedure
Subtask 26-21-00-720-056-B ** ON A/C NOT FOR ALL

A. Functional Test to Do a Check of the Distribution Piping for Leakage and Obstruction
(1) Obstruction Test

WARNING: BE VERY CAREFUL WHEN YOU MOVE A FULL FIRE EXTINGUISHER BOTTLE. A SUDDEN OR HEAVY SHOCK TO A FULL BOTTLE CAN CAUSE UNWANTED DISCHARGE AND INJURY TO PERSONS.

(a) On the related pylon:

NOTE: If the fire extinguisher bottles are not installed, go to the step (b).

1 Remove the 4 screws and washers which attach the aft fire-extinguisher bottle (10).
2 Disconnect the line (3) from the discharge head (4) and move the fire extinguisher bottle (10) to get access to the line (3).
3 Remove the 4 screws and washers which attach the forward fire-extinguisher bottle (13).
4 Disconnect the line (2) from the discharge head (7) and move the fire extinguisher bottle (13) to get access to the line (2).
(b) Install the clamp (5) 98D26203001000 TEST TOOL-ENG. FIRE EXTINGUISHING SYST.(IAEV2500) (98D26203001101) on the outlet A (detail E).
(c) Install the blank (8) 98D26203001000 TEST TOOL-ENG. FIRE EXTINGUISHING SYST.(IAEV2500) (98D26203001103) on the clamp (5).
(d) Install the manifold (12) 98D26203001000 TEST TOOL-ENG. FIRE EXTINGUISHING SYST.(IAEV2500) (98D26203001104) on the blank (8).
(e) Connect a AIR SOURCE 2 BAR (30 PSI) - REGULATED, FILTERED, DRY to the manifold (12).
(f) Open the compressed air source and make sure that the air flows from the outlets B, C, D, E and F (detail B) and G and H (detail C).
(g) Close the compressed air source.
(2) Leak Test
(a) Install the plug assy (14) 98D26203001000 TEST TOOL-ENG. FIRE EXTINGUISHING SYST.(IAEV2500) (98D26203001106) on the outlets G and H of the lines (2) and (3) (details C and D).
(b) Install the clamps (5) 98D26203001000 TEST TOOL-ENG. FIRE EXTINGUISHING SYST.(IAEV2500) (98D26203001101) on the outlets B and C (detail E).

NOTE: If necessary, remove the clips (22) and (24) to disengage the vibration harness to get access to the outlets B and C. Do as follows:

remove the nut (23) and the bolt (21).
Vibration Harness ** ON A/C NOT FOR ALL

(c) Install the blanks (6) 98D26203001000 TEST TOOL-ENG. FIRE EXTINGUISHING SYST.(IAEV2500) (98D26203001100) on the clamps (5).
(d) Install the blanks (9) 98D26203001000 TEST TOOL-ENG. FIRE EXTINGUISHING SYST.(IAEV2500) (98D26203000102) on the outlets D, E and F (details E, F and G).
(e) Pressurize the line to 2 bar (29 psi).
(f) Close the valve of the manifold assembly to isolate the extinguishing line.
(g) Monitor the lines (1), (2) and (3) for 10 minutes to:
1 Make sure that there is no leakage.
2 Make sure that the pressure does not decrease by more than 0.2 bar (3 psi).
(h) If the pressure decreases by more than 0.2 bar (3 psi), do a leak check:
1 Apply Testing Medium-Leak Detection - Oxygen System (Material No.14CCB6) on the lines (1), (2) and (3).
2 Examine the lines (1), (2) and (3) for leaks.
3 If you find a leak, replace the defective component(s) and do the leak check again.
4 Remove the Testing Medium-Leak Detection - Oxygen System (Material No.14CCB6) from the lines (1), (2) and (3) with a Textile-Lint free Cotton - (Material No.14SBA1) .
(i) Close the compressed air source.
(j) Open the drain valve to depressurize the extinguishing line.
(k) Disconnect the compressed air source.
(l) Disconnect the manifold (12) and the blank (8) from the clamp (5).
(m) Remove the blanks (6), (9), the clamps (5) and the plug assy (14).

NOTE: If removed, attach the clips (22) and (24) to the support tubes with the bolt (21) and the nut (23). TORQUE the nut (23) to between 0.495 and 0.405 m.daN (43.81 and 35.84 lbf.in )

Vibration Harness ** ON A/C NOT FOR ALL

5. Close-up
Subtask 26-21-00-860-059-B ** ON A/C NOT FOR ALL

A. Put the aircraft back to its initial configuration.
(1) If the bottles were not installed, install them (Ref. AMM TASK 26-21-41-400-001) and go to the step B.
(2) Connect the lines (2) and (3) to the discharge heads (7) and (4) (Ref. AMM TASK 26-21-41-400-001).
(3) Install the 4 screws and washers which attach the aft fire-extinguisher bottle (10).
(4) Install the 4 screws and washers which attach the forward fire-extinguisher bottle (13).

Subtask 26-21-00-865-070-A ** ON A/C NOT FOR ALL

B. 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	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/B	2WE1	Q44
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/A	1WE1	Q43
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/B	2WE2	Q42
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/A	1WE2	Q41

Subtask 26-21-00-410-062-A ** 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) On the left engine pylon, install the access doors:
415BL 415BR.
(3) On the right engine pylon, install the access doors:
425BL 425BR.
(4) Close the thrust reverser halves (Ref. AMM TASK 78-32-00-410-010):
(a) FOR [1000EM1] (ENGINE-1)
451AL, 452AR.
(b) FOR [1000EM2] (ENGINE-2)
461AL, 462AR.

Subtask 26-21-00-440-054-A ** ON A/C NOT FOR ALL

D. Activate the thrust reverser HCU (Ref. AMM TASK 78-30-00-440-012).

Subtask 26-21-00-410-063-A ** ON A/C NOT FOR ALL

E. Close Access
(1) Close the fan cowls:
(Ref. AMM TASK 71-13-00-410-010)
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR.
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR.

Subtask 26-21-00-942-061-A ** ON A/C NOT FOR ALL

F. Put the aircraft back to its initial configuration.
(1) Remove the WARNING NOTICE(S).
(2) Remove the access platform(s).

[Rev.10 from 2021] 2026.03.31 23:44:37 UTC