Leak Test of the Fuel Recirculation Cooling-System

TASK 28-16-00-790-001-A
Leak Test of the Fuel Recirculation Cooling-System

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.

FIN: 122QM ** ON A/C NOT FOR ALL
FIN: 123QM ** ON A/C NOT FOR ALL

1. Reason for the Job
To test for leaks in the fuel recirculation cooling-system when the oil temperature is at 100 DEG.C (212.00 DEG.F) or higher.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 5M (16 FT)- ADJUSTABLE
No specific	AR	SAFETY BARRIER(S)
No specific	AR	WARNING NOTICE(S)
101-00907	1	ADAPTER - FUEL RETURN VALVE
98D27803500001	1	LOCKING TOOL ZERO POS
TT1000A	1	DIGITAL TURBINE TEMPERATURE TEST SET
TT1200A	1	DIGITAL TURBINE TEMPERATURE TEST SET

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [122QM] (CHECK VALVE-FUEL RECIRCULATION, L)
471BL
FOR [123QM] (CHECK VALVE-FUEL RECIRCULATION, R)
482BR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 28-16-42-000-001-A	Removal of the Fuel Recirculation Check-valve
TASK 28-16-42-400-001-A	Installation of the Fuel Recirculation Check-valve
TASK 71-00-00-710-012-B	Test No.3 : Idle Leak Check
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 73-11-48-200-010-A	General Check of the Power Plant Flexible Fuel Tubes
TASK 78-30-00-040-013-A	Deactivation of the Thrust Reverser System for Flight
TASK 78-30-00-440-013-A	Activation of the Thrust Reverser System for Flight
Fuel Recirculation Check-Valve 122QM (123QM)
Barfield TT1000 Digital Turbine Test Set
Oil Temperature Thermocouple

3. Job Set-up
Subtask 28-16-00-941-058-B ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) In the cockpit, on flaps panel 114VU, make sure that the flap/slat control lever in the 0 deg (0 deg) position.
(2) Make sure that the 98D27803500001 LOCKING TOOL ZERO POS is on the flap/slat control lever.
(3) In the cockpit, on engine panel 115VU, put a WARNING NOTICE(S) to tell persons not to start the engine.
(4) Put a WARNING NOTICE(S) on the throttle control lever to tell persons not to operate the reverse system.
(5) Put the SAFETY BARRIER(S) in position.

Subtask 28-16-00-040-050-B ** ON A/C NOT FOR ALL

B. Deactivation of the Thrust Reverser (T/R) System

WARNING: YOU MUST DEACTIVATE THE THRUST REVERSER BEFORE YOU DO WORK ON OR AROUND IT. IF YOU DO NOT, THE THRUST REVERSER CAN OPERATE ACCIDENTALLY AND CAUSE AN INJURY AND/OR DAMAGE.

(1) Do the deactivation procedure of the T/R system (Ref. AMM TASK 78-30-00-040-013).

Subtask 28-16-00-865-057-A ** ON A/C NOT FOR ALL

C. Make sure that this(these) circuit breaker(s) is(are) closed:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	ENGINE/2/FADEC A/AND EIU 2	2KS2	A05
49VU	ENGINE/1/FADEC A/AND EIU 1	2KS1	A04
121VU	ENGINE/ENG2/FADEC B	4KS2	Q40
121VU	ENGINE/ENG1/FADEC B/AND EIU 1	4KS1	R41

Subtask 28-16-00-010-055-B ** ON A/C NOT FOR ALL

D. Get Access
(1) Open the fan cowls (Ref. AMM TASK 71-13-00-010-010).
(2) Put the ACCESS PLATFORM 5M (16 FT)- ADJUSTABLE below the applicable position:
(a) FOR [122QM] (CHECK VALVE-FUEL RECIRCULATION, L)
below zone 520
(b) FOR [123QM] (CHECK VALVE-FUEL RECIRCULATION, R)
below zone 620.
(3) Remove the applicable access panels:
(a) FOR [122QM] (CHECK VALVE-FUEL RECIRCULATION, L)
remove 471BL
(b) FOR [123QM] (CHECK VALVE-FUEL RECIRCULATION, R)
remove 482BR.

Subtask 28-16-00-480-052-B ** ON A/C NOT FOR ALL

E. Preparation for Test
(1) Disconnect the electrical connector (20) from the IDG oil temperature thermocouple (21).
(2) Connect the 101-00907 ADAPTER - FUEL RETURN VALVE to the electrical connector (20).
(3) Set the TT1000A DIGITAL TURBINE TEMPERATURE TEST SET or TT1200A DIGITAL TURBINE TEMPERATURE TEST SET as follows:

CAUTION: MAKE SURE THAT THE POLARITY IS CORRECT BEFORE YOU CONNECT THE TEST SET TO THE ADAPTOR LEAD. IF THE POLARITY IS NOT CORRECT YOU WILL CAUSE DAMAGE TO THE TEST SET.

(a) Set the switch (1) to the ON position.
(b) Set the "FUNCTION" switch (4) to the "RESISTANCE MEASURE" position.
(c) Set the "RESISTANCE RANGE" switch (7) to the 20 ohms position.
(d) Connect the test clips together.
(e) Push and hold the red "PUSH TO SET" button (5) and adjust the "SYSTEM RES" potentiometer (8) until a value of 1 ohm is shown on the Liquid Crystal Display (LCD) (2).
(f) Release the red "PUSH TO SET" button (5).
(g) Set the "FUNCTION" switch (4) to the "INDICATOR TEST" position.
(h) Set the "TEMP ADJ" potentiometer (3) to the "MIN" position.
(i) Connect the BLACK clip of the TT1000A DIGITAL TURBINE TEMPERATURE TEST SET or TT1200A DIGITAL TURBINE TEMPERATURE TEST SET to the BLACK wire of the 101-00907 ADAPTER - FUEL RETURN VALVE ((-) channel indicator). Connect the RED clip of the TT1000A DIGITAL TURBINE TEMPERATURE TEST SET or TT1200A DIGITAL TURBINE TEMPERATURE TEST SET to the RED wire of the 101-00907 ADAPTER - FUEL RETURN VALVE ((+) channel indicator).
(j) Set the "TEMP ADJ" potentiometer (3) so that 100 -0 DEG.C or +10 DEG.C (212.00 +0.00 DEG.F or +18.00 DEG.F) is shown on the LCD.

NOTE: The fuel is returned to the fuel tanks when the oil temperature is 100 DEG.C (212.00 DEG.F) or higher. The temperature is measured by the sensor installed on the IDG heat exchanger.

4. Procedure
Subtask 28-16-00-790-058-B ** ON A/C NOT FOR ALL

A. Functional Test of the Fuel Recirculation Cooling-System
(1) Do a minimum idle check (Ref. AMM TASK 71-00-00-710-012).
(2) Monitor the flexible fuel tube connection for fuel leaks (Ref. AMM TASK 73-11-48-200-010).
(3) Monitor the fuel recirculation check valve 122QM(123QM) for fuel leaks.

NOTE: If signs of leakage are found, the check valve must be replaced (Ref. AMM TASK 28-16-42-000-001) (Ref. AMM TASK 28-16-42-400-001).

5. Close-up
Subtask 28-16-00-080-052-B ** ON A/C NOT FOR ALL

A. Removal of the Test Equipment
(1) On the TT1000A DIGITAL TURBINE TEMPERATURE TEST SET or TT1200A DIGITAL TURBINE TEMPERATURE TEST SET, set the switch (1) to the OFF position.
(2) Disconnect the TT1000A DIGITAL TURBINE TEMPERATURE TEST SET or TT1200A DIGITAL TURBINE TEMPERATURE TEST SET from the 101-00907 ADAPTER - FUEL RETURN VALVE.
(3) Disconnect the 101-00907 ADAPTER - FUEL RETURN VALVE from the electrical connector (20).
(4) Connect the electrical connector (20) to the IDG oil temperature thermocouple (21).

Subtask 28-16-00-410-055-B ** ON A/C NOT FOR ALL

B. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the fan cowls (Ref. AMM TASK 71-13-00-410-010).
(3) Install the applicable access panels:
(a) FOR [122QM] (CHECK VALVE-FUEL RECIRCULATION, L)
install 471BL
(b) FOR [123QM] (CHECK VALVE-FUEL RECIRCULATION, R)
install 482BR.

Subtask 28-16-00-440-050-B ** ON A/C NOT FOR ALL

C. Reactivation of the T/R System
(1) Do the reactivation procedure of the T/R system (Ref. AMM TASK 78-30-00-440-013).

Subtask 28-16-00-942-055-B ** ON A/C NOT FOR ALL

D. Removal of Equipment
(1) 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.

[Rev.10 from 2021] 2026.04.01 07:16:33 UTC