Removal of the Main Oil/Fuel Heat Exchanger [CFMB]

TASK 79-21-20-000-002-A
Removal of the Main Oil/Fuel Heat Exchanger

FIN: 1000EM1 ** ON A/C NOT FOR ALL
FIN: 1000EM2 ** ON A/C NOT FOR ALL

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	CONTAINER 5 L (1.32 USGAL)
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [1000EM1] (ENGINE-1)
437AL, 438AR
FOR [1000EM2] (ENGINE-2)
447AL, 448AR

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 26-12-15-000-042-A	Removal of the Fan Fire Detectors
TASK 71-13-00-010-040-B	Opening of the Fan Cowl Doors
TASK 73-11-20-000-002-A	Removal of the Servo Fuel Heater
TASK 79-21-20-620-002-A	Preservation/Depreservation of the Main Oil/Fuel Heat Exchanger
Removal/Installation of the Main Oil/Fuel Heat Exchanger

3. Job Set-up
Subtask 79-21-20-941-053-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) On the center pedestal, on the ENG panel 115VU:
(a) 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 79-21-20-861-051-A ** ON A/C NOT FOR ALL

B. Energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-861-002).

Subtask 79-21-20-865-058-A ** ON A/C NOT FOR ALL

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
FOR FIN: 1000EM1 (ENGINE1)
49VU	FUEL/LP VALVE/MOT1/ENG1	1QG	A08
121VU	FUEL/LP VALVE/MOT2/ENG1	3QG	M25
FOR FIN: 1000EM2 (ENGINE2)
49VU	FUEL/LP VALVE/MOT1/ENG2	2QG	A09
121VU	FUEL/LP VALVE/MOT2/ENG2	4QG	M26

Subtask 79-21-20-010-056-A ** ON A/C NOT FOR ALL

D. Open the fan cowl doors: (Ref. AMM TASK 71-13-00-010-040)
(1) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(2) FOR [1000EM2] (ENGINE-2)
447AL 448AR

Subtask 79-21-20-010-057-A ** ON A/C NOT FOR ALL

E. Get Access
(1) Remove the fan zone fire detector, loops A and B (Ref. AMM TASK 26-12-15-000-042).
(2) Put a CONTAINER 5 L (1.32 USGAL) below the main oil/fuel heat exchanger.

4. Procedure
Subtask 79-21-20-020-051-A ** ON A/C NOT FOR ALL

A. Removal of the main oil/fuel heat exchanger.

CAUTION: USE TWO WRENCHES TO REMOVE OR INSTALL THE TUBE COUPLING NUTS:

ONE WRENCH TO HOLD THE UNION, AND
ONE TO LOOSEN OR TIGHTEN THE COUPLING NUT.

THIS PREVENTS DAMAGE TO THE PARTS.

(1) Remove the servo-fuel heater (70) (Ref. AMM TASK 73-11-20-000-002).
(2) Remove the FUEL-IN tube (40) from the main oil/fuel heat exchanger (60) and from the fuel hose (200) as follows:

PRE CFM SB 72-0515 and CFM SB 79-0022

(a) Remove the four bolts (180) and washers (170) and disconnect the FUEL IN tube (40) from the main oil/fuel heat exchanger (60). Remove the fan fire detector bracket (100). Remove and keep the gasket (160).

END OF PRE CFM SB 72-0515 and CFM SB 79-0022

POST CFM SB 72-0515 and CFM SB 79-0022

(b) Remove the four bolts (185) and disconnect the FUEL IN tube (40) from the main oil/fuel heat exchanger (60). Remove the fan fire detector bracket (100). Remove and keep the gasket (160).

NOTE: Make sure that the bolts (185) removed from the main oil/fuel heat exchanger port have a correct length to attach correctly the FUEL IN tube (40) on the port. If not, discard these bolts.

END CFM SB 72-0515 and CFM SB 79-0022

(c) Remove the bolt (210) and nut (220) which attach the items which follow:
1 Clamp (30) and plastic bushing (190) to the lower side of the bracket (20). Remove items (30) and (190).
2 Clamp (150) and plastic bushing (240) to the upper side of the bracket (20). Remove items (150) and (240).
(d) Fully loosen the coupling nut (10) to disconnect the FUEL IN tube (40) from the fuel hose (200) to IDG oil cooler.
(e) Remove the FUEL IN tube (40).
(3) Disconnect the drain tube (90) from the drain nipple (140) of the main oil/fuel heat exchanger (60).
(4) Remove the fuel tube (50) from the fuel pump nipple (250) to the fuel tube to FRV as follows:
(a) Fully loosen coupling nut (260) to disconnect fuel tube (50) from fuel pump nipple (250).
(b) Fully loosen coupling nut (230) to disconnect fuel tube (50) from fuel tube to FRV.
(c) Remove fuel tube (50).
(5) Remove the six nuts (130) and washers (120) which attach the main oil/fuel heat exchanger (60) to the fuel pump housing.
(6) Remove the main oil/fuel heat exchanger (60) from its mating flange and studs on the fuel pump housing. Remove and keep the gasket (110).
(7) If necessary, do the preservation procedure (Ref. AMM TASK 79-21-20-620-002).

[Rev.10 from 2021] 2026.04.01 03:39:15 UTC