Reactivation of the Yellow Power Accumulator

TASK 29-10-00-440-006-A
Reactivation of the Yellow Power Accumulator

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.

FIN: 3070GM

1. Reason for the Job
MMEL 29-10-04A
HYDRAULIC SYSTEM ACCUMULATOR
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	CONTAINER 5 L (1.32 USGAL)
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	1	WARNING NOTICE(S)
No specific	Torque wrench: range to between 10.7 and 9.7 m.daN (78.91 and 71.53 lbf.ft )

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.02ABA1)	Phosphate Ester Hydraulic Fluid-General Power - -

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
196BB

D. Referenced Information

REFERENCE	DESIGNATION
TASK 12-12-29-611-001-A	Fill the Hydraulic Fluid Reservoir with a Hand Pump
TASK 12-14-29-614-001-A	Fill the Hydraulic Power Accumulators with Nitrogen
TASK 29-00-00-864-001-A	Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 29-00-00-870-007-A	Bleeding Procedure of the Yellow Hydraulic System Downstream of the Engine Pump
TASK 29-00-00-910-002-A	Safety Procedures of the Hydraulic System
TASK 29-10-00-863-002-A	Pressurize the Yellow Hydraulic System with a Hydraulic Ground Power-Cart
TASK 29-10-00-864-002-A	Depressurize the Yellow Hydraulic System
TASK 29-13-42-000-001-A	Removal of the Yellow Power Accumulator
TASK 29-13-42-400-001-A	Installation of the Yellow Power Accumulator
TASK 29-14-00-614-001-A	Depressurization of the Hydraulic Reservoirs
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 29-23-00-860-001-A	Disconnection of the Isolation Coupling of the Power Transfer Unit (PTU)
TASK 29-23-00-860-002-A	Connection of the Isolation Coupling of the Power Transfer Unit (PTU)
Yellow Power Accumulator (3070GM)

3. Job Set-up
Subtask 29-10-00-865-093-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	HYD/HYD PWR/B WARN/& CTL	2702GJ	C12
** ON A/C NOT FOR ALL
121VU	HYDRAULIC/HYD POWER/Y	3803GX	N30
** ON A/C NOT FOR ALL
121VU	HYDRAULIC/HYD POWER/Y	3803GX	N31
** ON A/C ALL
123VU	B HYD/ELEC PUMP	2701GJ	AB09
123VU	Y HYD/ELEC/PUMP	3802GX	AB06
123VU	Y HYD/ELEC/ELEC PUMP/NORM	3801GX	AB03

Subtask 29-10-00-860-106-A

B. Aircraft Maintenance Configuration

WARNING: OBEY THE HYDRAULIC SAFETY PROCEDURES.

(1) Obey the hydraulic safety procedures (Ref. AMM TASK 29-00-00-910-002).
(2) Put the WARNING NOTICE(S) in position to tell persons not to pressurize the Yellow hydraulic system:

in the cockpit on the hydraulic section 40VU of the overhead panel,
on the ground service panel of the Yellow hydraulic system.

(3) Make sure that the Yellow hydraulic system is depressurized and put it in the maintenance configuration.
(Ref. AMM TASK 29-00-00-864-001).
(4) Depressurize the reservoir of the Yellow hydraulic system (Ref. AMM TASK 29-14-00-614-001).
(5) Disconnect the isolation coupling of the Power Transfer Unit (PTU) (Ref. AMM TASK 29-23-00-860-001).
(6) Put a CONTAINER 5 L (1.32 USGAL) below the accumulator to collect the unwanted hydraulic fluid.
(7) Make sure that the defective power accumulator is replaced (Ref. AMM TASK 29-13-42-000-001) and (Ref. AMM TASK 29-13-42-400-001).

Subtask 29-10-00-010-081-A

C. Open the access door 196BB.

4. Procedure
Subtask 29-10-00-020-061-A

A. Remove the Blanking Caps

CAUTION: USE A SECOND WRENCH TO APPLY COUNTERTORQUE TO THE UNION WHEN YOU DISCONNECT/CONNECT HYDRAULIC LINES ON UNIONS. IF YOU DO NOT USE THE SECOND WRENCH, THERE IS A RISK THAT YOU WILL LOOSEN OR TIGHTEN THE UNION TOO MUCH.

(1) If installed remove the blanking cap from the union (2) of the power accumulator (3).
(2) Remove the blanking cap from the union (13) of the HP-manifold (14).

Subtask 29-10-00-420-058-A ** ON A/C NOT FOR ALL

B. Installation of the Hydraulic Pipe

CAUTION: YOU MUST INSTALL HYDRAULIC TUBES WITH HYDRAULIC FLUID AS LUBRICANT.

(1) Clean the component interfaces and the adjacent area.
(2) Do an inspection of the component interfaces and the adjacent area.
(3) Remove the blanking caps from the line end fittings (1) and (12) of the pipe (6).

WARNING: OBEY THE HYDRAULIC SAFETY PROCEDURES.

(4) Apply the Phosphate Ester Hydraulic Fluid-General Power - - (Material No.02ABA1) to the threads of the line end fittings (1) and (12).
(5) Fill the power accumulator (3) with the Phosphate Ester Hydraulic Fluid-General Power - - (Material No.02ABA1) .
(6) Install the pipe (6) loosely on the union (2) of the power accumulator (3) and on the union (13) of the HP-manifold (14).
(7) Install the clamp-block halves (8) and (9) with the bolts (7) and the nuts (10) to attach the pipe (6) to the bracket (11).
(8) TORQUE the line end fittings (1) and (12) to between 10.7 and 9.7 m.daN (78.91 and 71.53 lbf.ft )

Subtask 29-10-00-420-058-B ** ON A/C NOT FOR ALL

B. Installation of the Hydraulic Pipe

CAUTION: YOU MUST INSTALL HYDRAULIC TUBES WITH HYDRAULIC FLUID AS LUBRICANT.

WARNING: OBEY THE HYDRAULIC SAFETY PROCEDURES.

NOTE: It is not permitted to use high-density fluid Skydrol 500B-4.

(6) Install the pipe (6) loosely on the union (2) of the power accumulator (3) and on the union (13) of the HP-manifold (14).
(7) Install the clamp-block halves (8) and (9) with the bolts (7) and the nuts (10) to attach the pipe (6) to the bracket (11).
(8) TORQUE the line end fittings (1) and (12) to between 10.7 and 9.7 m.daN (78.91 and 71.53 lbf.ft )

Subtask 29-10-00-865-094-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	HYD/HYD PWR/B WARN/& CTL	2702GJ	C12
** ON A/C NOT FOR ALL
121VU	HYDRAULIC/HYD POWER/Y	3803GX	N30
** ON A/C NOT FOR ALL
121VU	HYDRAULIC/HYD POWER/Y	3803GX	N31
** ON A/C ALL
123VU	B HYD/ELEC PUMP	2701GJ	AB09
123VU	Y HYD/ELEC/PUMP	3802GX	AB06
123VU	Y HYD/ELEC/ELEC PUMP/NORM	3801GX	AB03

Subtask 29-10-00-790-058-A

D. Test of the Power Accumulator

WARNING: MAKE SURE THAT THE TRAVEL RANGES OF THE FLIGHT CONTROLS SURFACES ARE CLEAR. MOVEMENT OF FLIGHT CONTROLS CAN CAUSE INJURY TO PERSONS AND/OR DAMAGE TO EQUIPMENT.

(1) Fill the power accumulator (3) with nitrogen (Ref. AMM TASK 12-14-29-614-001).
(2) Remove the WARNING NOTICE(S) from the ground service panel of the Yellow hydraulic system and from the cockpit .
(3) Pressurize the reservoir of the Yellow hydraulic system (Ref. AMM TASK 29-14-00-614-002).
(4) Make sure that the fluid level in the reservoir of the Yellow hydraulic system is correct. Add fluid as necessary (Ref. AMM TASK 12-12-29-611-001).
(5) Pressurize the Yellow hydraulic system (Ref. AMM TASK 29-10-00-863-002).
(6) After 5 minutes, examine the connections of the power accumulator (3), the pipe (6) and the HP-manifold (14). Make sure that there are no hydraulic fluid or nitrogen leaks.
(7) Depressurize the Yellow hydraulic system (Ref. AMM TASK 29-10-00-864-002).
(8) Do the bleeding procedure of the Yellow hydraulic system downstream of the engine pump (Ref. AMM TASK 29-00-00-870-007).

NOTE: When you do the bleeding procedure, nitrogen, which has gone into the hydraulic system from the defective accumulator, is removed.

5. Close-up
Subtask 29-10-00-410-081-A

A. Put the aircraft back to the serviceable condition.
(1) Connect the PTU isolation coupling (Ref. AMM TASK 29-23-00-860-002).
(2) Remove the CONTAINER 5 L (1.32 USGAL) from below the power accumulator.
(3) Make sure that the work area is clean and clear of tools and other items.
(4) Close the access door 196BB.
(5) Remove the entry from the log book.

[Rev.10 from 2021] 2026.04.01 00:14:04 UTC