Removal of the Fan Area Fire-Detection Elements

TASK 26-12-18-000-801-A
Removal of the Fan Area Fire-Detection Elements

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE PARTS AFTER THE ENGINE SHUTDOWN. USE APPLICABLE THERMAL GLOVES. THE ENGINE PARTS CAN STAY HOT FOR ONE HOUR AFTER SHUTDOWN AND CAN BURN YOU.

ZONE: 430
ZONE: 440
FIN: 4000WD1
FIN: 4000WD2
FIN: 4002WD1
FIN: 4002WD2

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

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE
No specific	AR	CAP - PROTECTION
No specific	AR	COVER - PROTECTION
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
430	ENG 1 AIR INTAKE, FAN AND ACCESS GEARBOX
440	ENG 2 AIR INTAKE, FAN AND ACCESS GEARBOX
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL, 438AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL, 448AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 24-42-00-861-001-A	Energize the Ground Service Network from the External Power
TASK 71-13-00-010-803-A	Opening of the Fan Cowl Doors
Fan Area Fire-Detection Elements

3. Job Set-up
Subtask 26-12-18-861-050-A

A. Energize the ground service network
(Ref. AMM TASK 24-42-00-861-001).

Subtask 26-12-18-941-050-A

B. Safety Precautions
(1) On the center pedestal, on ENG panel 115VU:
(a) Make sure that the ENG/MODE selector switch is in the NORM position.
(b) Make sure that the ENG/MASTER 1(2) control switch was in the OFF position not less than five minutes before you do this procedure.
(c) Put WARNING NOTICE(S) in position to tell persons not to operate the ENG/MODE selector switch and the ENG/MASTER 1(2) control switch.
(2) On the ENG section of maintenance panel 50VU:
(a) Make sure that the ON legend of the FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) in position to tell persons not to energize FADEC 1(2).

Subtask 26-12-18-865-050-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
FOR FIN: 4020KM1 (POWER PLANTDEMOUNTABLE, ENGINE 1)
49VU	ENGINE/1/FIRE DET/LOOP A	7WD1	A06
121VU	ENGINE/ENG1/FIRE DET/LOOP B	8WD1	Q38
FOR FIN: 4020KM2 (POWER PLANTDEMOUNTABLE, ENGINE 2)
49VU	ENGINE/2/FIRE DET/LOOP B	8WD2	A07
121VU	ENGINE/ENG2/FIRE DET/LOOP A	7WD2	Q39

Subtask 26-12-18-010-050-A

D. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR
(2) Put an ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position.

4. Procedure
Subtask 26-12-18-020-050-A

A. Removal of the Fan Area Fire-Detection Elements

Fan Area Fire-Detection Elements

(1) Installation of protection covers

CAUTION: INSTALL PROTECTION COVERS ON ALL THE OPENINGS IMMEDIATELY TO PREVENT DAMAGE TO THE ENGINE.

(a) Install COVER - PROTECTION and CAP - PROTECTION on all open ports, open tubes, open hoses and connectors.
(2) Remove the fire detector elements from the Accessory Gearbox (AGB) as follows:
(a) Remove the nuts (2) and (3) that attach the harness (1) connectors to the responder (6).
(b) Remove the harness (1) leads from the terminals on the responder (6), and remove the plastic jaws from the spring clips on the responder retention bracket (4).
(c) Remove the nuts (28) and (29) that attach the harness (27) connectors to the responder (32).
(d) Remove the harness (27) leads from the terminals on the responder (32), and remove the plastic jaws from the spring clips on the responder retention bracket (30).
(e) Turn the fastener (8) a quarter turn counterclockwise and open the clip (7).
(f) Turn the fastener (10) a quarter turn counterclockwise and open the clip (9).
(g) Turn the fastener (12) a quarter turn counterclockwise and open the clip (11).
(h) Turn the fastener (14) a quarter turn counterclockwise and open the clip (13).
(i) Turn the fastener (16) a quarter turn counterclockwise and open the clip (15).
(j) Turn the fastener (18) a quarter turn counterclockwise and open the clip (17).
(k) Turn the fastener (20) a quarter turn counterclockwise and open the clip (19).
(l) Turn the fastener (22) a quarter turn counterclockwise and open the clip (21).
(m) Turn the fastener (24) a quarter turn counterclockwise and open the clip (23).
(n) Turn the fastener (26) a quarter turn counterclockwise and open the clip (25).
(o) Disengage the fire detection elements (33) and (34) from the clips.
(p) Remove the related plastic jaws from the sensing elements (33) and (34) and retain them.
(q) Remove the four bolts (5) that attach the responder retention bracket (4) to the AGB bracket.
(r) Remove the four bolts (31) that attach the responder retention bracket (30) to the AGB bracket.
(s) Remove the fire detection elements from the engine.
(3) Remove the 6 o'clock fire detection elements as follows:
(a) Remove the two nuts (36) and (37) that attach the harness (35) connectors to the responder (40).
(b) Move the end of the left harness (35) away from the responder (40).
(c) Remove the nuts (64) and (65) that attach the harness (63) connectors to the responder (68).
(d) Move the end of the right harness (63) away from the responder (68).
(e) Turn the fastener (42) a quarter turn counterclockwise and open the clip (41).
(f) Turn the fastener (44) a quarter turn counterclockwise and open the clip (43).
(g) Turn the fastener (46) a quarter turn counterclockwise and open the clip (45).
(h) Turn the fastener (48) a quarter turn counterclockwise and open the clip (47).
(i) Turn the fastener (50) a quarter turn counterclockwise and open the clip (49).
(j) Turn the fastener (52) a quarter turn counterclockwise and open the clip (51).
(k) Turn the fastener (54) a quarter turn counterclockwise and open the clip (53).
(l) Turn the fastener (56) a quarter turn counterclockwise and open the clip (55).
(m) Turn the fastener (58) a quarter turn counterclockwise and open the clip (57).
(n) Turn the fastener (60) a quarter turn counterclockwise and open the clip (59).
(o) Turn the fastener (62) a quarter turn counterclockwise and open the clip (61).
(p) Disengage the fire detection elements (69) and (70) from the clips.
(q) Remove the related plastic jaws from the fire detection elements (69) and (70) and retain them.
(r) Remove the four bolts (39) that attach the responder retention bracket (38) to the rail bracket.
(s) Remove the four bolts (67) that attach the responder retention bracket (66) to the rail bracket.
(t) Remove the fire detection elements from the engine.

[Rev.10 from 2021] 2026.04.01 13:04:34 UTC