DOC AIRBUS | AMM A320FInstallation of the Hydraulic Control Unit [CFMI]
TASK 78-31-51-400-040-A
Installation of the Hydraulic Control Unit
1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Consumable Materials
C. Work Zones and Access Panels
D. Expendable Parts
E. Referenced Information
3. Job Set-up
Subtask 78-31-51-860-053-A ** ON A/C NOT FOR ALL
Subtask 78-31-51-420-058-A ** ON A/C NOT FOR ALL
Subtask 78-31-51-942-052-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.02 06:38:06 UTC
Installation of the Hydraulic Control Unit
1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Consumable Materials
| REFERENCE | DESIGNATION |
|---|---|
| (Material No.CP1039) | acetone |
| (Material No.CP1041) | isopropyl alcohol |
| (Material No.CP2011) | stoddard solvent |
| (Material No.CP2212) | hydraulic fluid NSA-307-110 type 4 |
| (Material No.CP2318) | blindexite RT 342-2 |
| (Material No.CP2559) | ardrox 552 |
| (Material No.CP2560) | turco ind 79 |
| (Material No.CP2566) | mag-chem teksol |
| (Material No.CP2584) | degreasol 99 R |
| (Material No.CP2656) | mag-chem skysol |
| (Material No.CP8001) | lockwire 0.032 in. (0.8 mm) dia. |
| (Material No.CP8002) | lockwire 0.032 in. (0.8 mm) dia |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| FOR [1000EM1] (ENGINE-1) | |
| 437AL, 438AR, 452AR | |
| FOR [1000EM2] (ENGINE-2) | |
| 447AL, 448AR, 462AR | |
| FIG.ITEM | DESIGNATION | IPC-CSN |
|---|---|---|
| 145 | PREFORMED PACKINGS | AIPC 78-31-51-01-030 |
| 125 | PREFORMED PACKING | AIPC 78-31-51-01-050 |
| 170 | PREFORMED PACKING | AIPC 78-31-51-01-050 |
| 150 | PREFORMED PACKING | AIPC 78-31-51-01-080 |
| 155 | PREFORMED PACKING | AIPC 78-31-51-01-100 |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 29-14-00-614-002-A | Pressurization of the Hydraulic Reservoirs through the Ground Connector |
| TASK 29-14-00-614-002-A-01 | Pressurization of the Hydraulic Reservoirs with the Auxiliary Power Unit (APU) |
| TASK 71-13-00-010-040-A | Opening of the Fan Cowl Doors |
| TASK 71-13-00-410-040-A | Closing of the Fan Cowl Doors |
| TASK 78-30-00-081-041-A | Make the Thrust Reverser Serviceable after Maintenance |
| TASK 78-30-00-481-041-A | Make the Thrust Reverser Unserviceable for Maintenance |
| TASK 78-30-00-710-040-A | Thrust Reverser Hydraulic System Bleed Procedure |
| TASK 78-31-00-710-040-A | Operational Test of the Thrust Reverser System |
| TASK 78-31-00-710-040-A-01 | Operational Test of the Thrust Reverser without CFDS - Engine not Running |
| TASK 78-31-00-710-040-A-02 | Operational Test of the Thrust Reverser without CFDS - Engine Running |
| TASK 78-36-00-010-040-A | Opening of the Thrust Reverser Doors |
| TASK 78-36-00-410-040-A | Closing of the Thrust Reverser Doors |
Hydraulic Control UnitSubtask 78-31-51-860-053-A ** ON A/C NOT FOR ALL
A. Aircraft Maintenance Configuration
(1) On the center pedestal, on the ENG panel 115VU, make sure that a WARNING NOTICE(S) is in position to tell persons not to start the engine.
(2) On the overhead maintenance panel 50VU, make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off. Make sure that a WARNING NOTICE(S) is in position to tell persons not to energize the FADEC 1(2).
(3) Make sure that the ACCESS PLATFORM 1M(3 FT) is in position.
Subtask 78-31-51-010-067-A ** ON A/C NOT FOR ALL (1) On the center pedestal, on the ENG panel 115VU, make sure that a WARNING NOTICE(S) is in position to tell persons not to start the engine.
(2) On the overhead maintenance panel 50VU, make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off. Make sure that a WARNING NOTICE(S) is in position to tell persons not to energize the FADEC 1(2).
(3) Make sure that the ACCESS PLATFORM 1M(3 FT) is in position.
B. Get Access
(1) Make sure that the fan cowl doors are open (Ref. AMM TASK 71-13-00-010-040):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(2) Make sure that the right thrust reverser is open (Ref. AMM TASK 78-36-00-010-040):
(a) FOR [1000EM1] (ENGINE-1)
452AR
(b) FOR [1000EM2] (ENGINE-2)
462AR
Subtask 78-31-51-040-060-A ** ON A/C NOT FOR ALL 4. Procedure(1) Make sure that the fan cowl doors are open (Ref. AMM TASK 71-13-00-010-040):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(2) Make sure that the right thrust reverser is open (Ref. AMM TASK 78-36-00-010-040):
(a) FOR [1000EM1] (ENGINE-1)
452AR
(b) FOR [1000EM2] (ENGINE-2)
462AR
Subtask 78-31-51-420-058-A ** ON A/C NOT FOR ALL
A. Preparation for Installation
(1) Remove the protective caps from the tubes, hoses and HCU fittings.
(2) Remove the CAP-BLANKING from each electrical connector and receptacle.
(3) Make sure there is no unwanted matter inside the HCU ports and orifices.
(4) Lubricate the new preformed packings with hydraulic fluid NSA-307-110 type 4 (Material No.CP2212) .
(5) Apply hydraulic fluid NSA-307-110 type 4 (Material No.CP2212) to threads of the unions.
(6) Install the unions and packings on the HCU as follows:
(a) Put the AIPC 78-31-51-01-050 PREFORMED PACKING (125) on the union (130) and the AIPC 78-31-51-01-050 PREFORMED PACKING (170) on the union (165).
(b) Install the union (130) in the inlet supply port on the left side of the HCU.
(c) Install the union (165) in the head supply port on the right side of the HCU.
(d) TORQUE both unions to between 700 and 610 lbf.in (7.91 and 6.89 m.daN )
.
(e) Put the AIPC 78-31-51-01-080 PREFORMED PACKING (150) on the union (135).
(f) Install the union (135) in the return port on the left side of the HCU.
(g) TORQUE the union (135) to between 1002 and 906 lbf.in (11.32 and 10.24 m.daN ).
(h) Put the AIPC 78-31-51-01-030 PREFORMED PACKINGS (145) on the unions (140).
(i) Install one union (140) in the lock-in port on the left side of the HCU.
(j) Install the other union (140) in the lock-out port on the right side of the HCU.
(k) TORQUE both unions to between 300 and 260 lbf.in (3.39 and 2.94 m.daN ).
(l) Put the AIPC 78-31-51-01-100 PREFORMED PACKING (155) on the union (160).
(m) Install the union (160) in the rod supply port on the right side of the HCU.
(n) TORQUE the union (160) to between 410 and 370 lbf.in (4.63 and 4.18 m.daN ).
Subtask 78-31-51-420-059-B ** ON A/C NOT FOR ALL (1) Remove the protective caps from the tubes, hoses and HCU fittings.
(2) Remove the CAP-BLANKING from each electrical connector and receptacle.
(3) Make sure there is no unwanted matter inside the HCU ports and orifices.
(4) Lubricate the new preformed packings with hydraulic fluid NSA-307-110 type 4 (Material No.CP2212) .
(5) Apply hydraulic fluid NSA-307-110 type 4 (Material No.CP2212) to threads of the unions.
(6) Install the unions and packings on the HCU as follows:
(a) Put the AIPC 78-31-51-01-050 PREFORMED PACKING (125) on the union (130) and the AIPC 78-31-51-01-050 PREFORMED PACKING (170) on the union (165).
(b) Install the union (130) in the inlet supply port on the left side of the HCU.
(c) Install the union (165) in the head supply port on the right side of the HCU.
(d) TORQUE both unions to between 700 and 610 lbf.in (7.91 and 6.89 m.daN )
. (e) Put the AIPC 78-31-51-01-080 PREFORMED PACKING (150) on the union (135).
(f) Install the union (135) in the return port on the left side of the HCU.
(g) TORQUE the union (135) to between 1002 and 906 lbf.in (11.32 and 10.24 m.daN )
. (h) Put the AIPC 78-31-51-01-030 PREFORMED PACKINGS (145) on the unions (140).
(i) Install one union (140) in the lock-in port on the left side of the HCU.
(j) Install the other union (140) in the lock-out port on the right side of the HCU.
(k) TORQUE both unions to between 300 and 260 lbf.in (3.39 and 2.94 m.daN )
. (l) Put the AIPC 78-31-51-01-100 PREFORMED PACKING (155) on the union (160).
(m) Install the union (160) in the rod supply port on the right side of the HCU.
(n) TORQUE the union (160) to between 410 and 370 lbf.in (4.63 and 4.18 m.daN )
. B. Install the HCU on the Engine
(1) Install the thermal blankets on the HCU if required, as follows:
(a) Put the thermal blankets (175) and (180) on the HCU (20).
(b) Make sure that the thermal blankets have the same shape as the HCU. There should be clearance of 0.10 in. (2.54 mm) between the blankets and the adjacent parts.
(2) Attach the interface blancket (15) to the HCU with the bolts (120). TORQUE the bolts (120) to between 70 and 61 lbf.in (0.79 and 0.69 m.daN ).
(3) Apply a layer of blindexite RT 342-2 (Material No.CP2318) to the HCU mating surface.
(4) Install the two lower bolts (115) on the HCU mounting flange.
(5) Position the HCU (20) against the foward frame and install the other two bolts (115).
(6) TORQUE the bolts (115) to between 160 and 140 lbf.in (1.81 and 1.58 m.daN ).
Subtask 78-31-51-420-057-A ** ON A/C NOT FOR ALL (1) Install the thermal blankets on the HCU if required, as follows:
(a) Put the thermal blankets (175) and (180) on the HCU (20).
(b) Make sure that the thermal blankets have the same shape as the HCU. There should be clearance of 0.10 in. (2.54 mm) between the blankets and the adjacent parts.
(2) Attach the interface blancket (15) to the HCU with the bolts (120). TORQUE the bolts (120) to between 70 and 61 lbf.in (0.79 and 0.69 m.daN )
. (3) Apply a layer of blindexite RT 342-2 (Material No.CP2318) to the HCU mating surface.
(4) Install the two lower bolts (115) on the HCU mounting flange.
(5) Position the HCU (20) against the foward frame and install the other two bolts (115).
(6) TORQUE the bolts (115) to between 160 and 140 lbf.in (1.81 and 1.58 m.daN )
. C. Connect the Pipes that Follow to the Right Side of the HCU
(1) Connect the head supply pipe (110) to the HCU (20).
(2) TORQUE the coupling nut to between 500 and 450 lbf.in (5.65 and 5.09 m.daN ).
(3) Attach the head supply pipe (110) to the interface bracket (15) with the nut (80).
(4) TORQUE the nut (80) to between 700 and 610 lbf.in (7.91 and 6.89 m.daN ).
(5) Attach the latch return pipe (35) to the interface bracket (15) with the nut (85).
(6) TORQUE the nut (85) to between 300 and 260 lbf.in (3.39 and 2.94 m.daN ).
(8) TORQUE the coupling nut to between 260 and 235 lbf.in (2.94 and 2.66 m.daN ).
(9) Attach the rod supply pipe (75) to the interface bracket (15) with the nut (105).
(10) TORQUE the nut (105) to between 420 and 376 lbf.in (4.75 and 4.25 m.daN ).
(11) Connect the latch supply pipe (70) to the HCU (20).
(12) TORQUE the coupling nut on the latch supply pipe (70) to between 150 and 130 lbf.in (1.70 and 1.47 m.daN ).
Subtask 78-31-51-420-060-A ** ON A/C NOT FOR ALL (1) Connect the head supply pipe (110) to the HCU (20).
(2) TORQUE the coupling nut to between 500 and 450 lbf.in (5.65 and 5.09 m.daN )
. (3) Attach the head supply pipe (110) to the interface bracket (15) with the nut (80).
(4) TORQUE the nut (80) to between 700 and 610 lbf.in (7.91 and 6.89 m.daN )
. (5) Attach the latch return pipe (35) to the interface bracket (15) with the nut (85).
(6) TORQUE the nut (85) to between 300 and 260 lbf.in (3.39 and 2.94 m.daN )
. NOTE: A clearance of 0.15 in. to 0.23 in. (4 mm to 6 mm) is required between the HCU thermal blankets and the Return Pipe (35) of the Right Latch.
(7) Connect the rod supply pipe (75) to the HCU (20). (8) TORQUE the coupling nut to between 260 and 235 lbf.in (2.94 and 2.66 m.daN )
. (9) Attach the rod supply pipe (75) to the interface bracket (15) with the nut (105).
(10) TORQUE the nut (105) to between 420 and 376 lbf.in (4.75 and 4.25 m.daN )
. (11) Connect the latch supply pipe (70) to the HCU (20).
(12) TORQUE the coupling nut on the latch supply pipe (70) to between 150 and 130 lbf.in (1.70 and 1.47 m.daN )
. D. Connect the Pipes and Hoses that Follow to the Left Side of the HCU
(1) Connect the supply hose (45) to the HCU (20).
(2) TORQUE the coupling nut on the hose (45) to between 732 and 660 lbf.in (8.27 and 7.46 m.daN ).
(3) Connect the return hose (50) to the HCU (20).
(4) TORQUE the coupling nut on the hose (50) to between 520 and 470 lbf.in (5.88 and 5.31 m.daN ).
(5) Connect the latch return hose (40) to the HCU (20).
(6) TORQUE the coupling nut on the hose (40) to between 125 and 113 lbf.in (1.41 and 1.28 m.daN ).
(7) Connect the latch supply hose (55) to the latch return pipe (35) on the interface bracket (15).
(8) TORQUE the coupling nut on the hose (55) to between 125 and 113 lbf.in (1.41 and 1.28 m.daN ).
(9) Connect the head supply hose (60) to the head supply pipe (110) on the interface bracket (15).
(10) TORQUE the coupling nut on the hose (60) to between 600 and 540 lbf.in (6.78 and 6.10 m.daN ).
(11) Connect the rod supply hose (65) to the rod supply pipe (75) on the interface bracket (15).
(12) TORQUE the coupling nut on the hose (65) to between 300 and 270 lbf.in (3.39 and 3.05 m.daN ).
(13) Put the clamp (10) on the thrust reverser harness (30). Attach the clamp (10) to the interface bracket (15) with the bolt (5) and the nut (25).
(14) TORQUE the nut (25) to between 40 and 30 lbf.in (0.45 and 0.34 m.daN ).
(15) Connect the electrical connector 4101KS-A to solenoid A of the HCU.
(17) Connect the electrical connector 4102KS-A to the HCU pressure switch.
5. Close-up(1) Connect the supply hose (45) to the HCU (20).
(2) TORQUE the coupling nut on the hose (45) to between 732 and 660 lbf.in (8.27 and 7.46 m.daN )
. (3) Connect the return hose (50) to the HCU (20).
(4) TORQUE the coupling nut on the hose (50) to between 520 and 470 lbf.in (5.88 and 5.31 m.daN )
. (5) Connect the latch return hose (40) to the HCU (20).
(6) TORQUE the coupling nut on the hose (40) to between 125 and 113 lbf.in (1.41 and 1.28 m.daN )
. (7) Connect the latch supply hose (55) to the latch return pipe (35) on the interface bracket (15).
(8) TORQUE the coupling nut on the hose (55) to between 125 and 113 lbf.in (1.41 and 1.28 m.daN )
. (9) Connect the head supply hose (60) to the head supply pipe (110) on the interface bracket (15).
(10) TORQUE the coupling nut on the hose (60) to between 600 and 540 lbf.in (6.78 and 6.10 m.daN )
. (11) Connect the rod supply hose (65) to the rod supply pipe (75) on the interface bracket (15).
(12) TORQUE the coupling nut on the hose (65) to between 300 and 270 lbf.in (3.39 and 3.05 m.daN )
. (13) Put the clamp (10) on the thrust reverser harness (30). Attach the clamp (10) to the interface bracket (15) with the bolt (5) and the nut (25).
(14) TORQUE the nut (25) to between 40 and 30 lbf.in (0.45 and 0.34 m.daN )
. (15) Connect the electrical connector 4101KS-A to solenoid A of the HCU.
NOTE: If necessary, use the PLIERS - NOSE, SOFT, LONG to tighten the electrical connectors.
(16) Connect the electrical connector 4101KS-B to solenoid B of the HCU. (17) Connect the electrical connector 4102KS-A to the HCU pressure switch.
Subtask 78-31-51-942-052-A ** ON A/C NOT FOR ALL
A. Remove Drain Can from Under the HCU
(1) Remove the protective cover and inspect the forward compressor cases to ensure that no thrust reverser hydraulic fluid has come in contact with the titanium.
Subtask 78-31-51-100-050-A ** ON A/C NOT FOR ALL (1) Remove the protective cover and inspect the forward compressor cases to ensure that no thrust reverser hydraulic fluid has come in contact with the titanium.
B. If Thrust Reverser Hydraulic Fluid Has Come in Contact with a Titanium Part, the Following Cleaning Procedure Should Be Used
(1) Wipe off affected area using a clean, dry cloth or paper towel.
(2) Then thoroughly wash the affected area:
(3) Dry the area with a clean, dry cloth or paper towel.
Subtask 78-31-51-210-056-A ** ON A/C NOT FOR ALL (1) Wipe off affected area using a clean, dry cloth or paper towel.
(2) Then thoroughly wash the affected area:
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(a) Then thoroughly wash the affected area with a cloth or paper towel wetted with isopropyl alcohol (Material No.CP1041) or acetone (Material No.CP1039) or stoddard solvent (Material No.CP2011) or ardrox 552 (Material No.CP2559) or turco ind 79 (Material No.CP2560) or mag-chem teksol (Material No.CP2566) or degreasol 99 R (Material No.CP2584) or mag-chem skysol (Material No.CP2656) . (3) Dry the area with a clean, dry cloth or paper towel.
C. Make Sure that the Clogging Indicator Does Not Come Out
(1) If the red clogging indicator has come out set it operationnal as follows:
(2) Cut the lockwire, untighten and remove the transparent cap.
(3) Push the red indicator in.
(4) Install and hand tighten the cap. Safety withCP8001 lockwire 0.032 in. (0.8 mm) dia. CP8002 lockwire 0.032 in. (0.8 mm) dia
Subtask 78-31-51-410-061-A ** ON A/C NOT FOR ALL (1) If the red clogging indicator has come out set it operationnal as follows:
(2) Cut the lockwire, untighten and remove the transparent cap.
(3) Push the red indicator in.
(4) Install and hand tighten the cap. Safety with
D. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the right thrust reverser (Ref. AMM TASK 78-36-00-410-040):
(a) FOR [1000EM1] (ENGINE-1)
452AR
(b) FOR [1000EM2] (ENGINE-2)
462AR
Subtask 78-31-51-440-057-A ** ON A/C NOT FOR ALL Subtask 78-31-51-410-062-A ** ON A/C NOT FOR ALL (1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the right thrust reverser (Ref. AMM TASK 78-36-00-410-040):
(a) FOR [1000EM1] (ENGINE-1)
452AR
(b) FOR [1000EM2] (ENGINE-2)
462AR
F. Close Access
(1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-040):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).
Subtask 78-31-51-614-053-A ** ON A/C NOT FOR ALL (1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-040):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).
G. Pressurize the aircraft hydraulic systems
(1) For engine 1 pressurize the Green hydraulic reservoir (Ref. AMM TASK 29-14-00-614-002).
(2) For engine 2 pressurize the Yellow hydraulic reservoir (Ref. AMM TASK 29-14-00-614-002).
Subtask 78-31-51-710-054-A ** ON A/C NOT FOR ALL Subtask 78-31-51-210-057-A ** ON A/C NOT FOR ALL (1) For engine 1 pressurize the Green hydraulic reservoir (Ref. AMM TASK 29-14-00-614-002).
(2) For engine 2 pressurize the Yellow hydraulic reservoir (Ref. AMM TASK 29-14-00-614-002).
I. Examine the Filter Clogging Indicator on the HCU.
(1) If the red end of the indicator has come out, set it to the operational position, as follows:
(a) Remove the retaining ring and the glass bowl.
(b) Push the red indicator to the normal (operational) position.
(c) Install the retaining ring and the glass bowl.
(2) Do one more deploy-to-stow cycle of the thrust reverser. Make sure that the clogging indicator on the HCU is in the operational position (Ref. AMM TASK 78-31-00-710-040).
(1) If the red end of the indicator has come out, set it to the operational position, as follows:
(a) Remove the retaining ring and the glass bowl.
(b) Push the red indicator to the normal (operational) position.
(c) Install the retaining ring and the glass bowl.
(2) Do one more deploy-to-stow cycle of the thrust reverser. Make sure that the clogging indicator on the HCU is in the operational position (Ref. AMM TASK 78-31-00-710-040).