Removal of the Igniter Plug [IAE]

TASK 74-21-41-000-010-A
Removal of the Igniter Plug

WARNING: DO NOT TOUCH THE HIGH TENSION LEADS OF THE IGNITOR PLUGS FOR AT LEAST ONE MINUTE AFTER THE APPLICABLE CIRCUIT BREAKERS ARE OPEN. THE ELECTRICAL DISCHARGE OF THE HIGH ENERGY UNIT IS DANGEROUS AND CAN KILL.

CAUTION: DO NOT BEND THE ELECTRICAL CABLE CONDUIT TOO MUCH WHEN YOU DISCONNECT THE ELECTRICAL CONNECTOR. THE CONDUIT CAN BE DAMAGED AND CAN CAUSE ELECTRICAL CIRCUIT DEFECTS.

FIN: 4001JH1 ** ON A/C NOT FOR ALL
FIN: 4001JH2 ** ON A/C NOT FOR ALL

1. Reason for the Job
There are two ignitor plugs on each engine. This TASK gives the procedure to remove one ignitor plug. Use the same procedure to remove the second ignitor plug.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 1M(3 FT)
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
FOR [1000EM1] (ENGINE-1)
437AL, 438AR, 452AR
FOR [1000EM2] (ENGINE-2)
447AL, 448AR, 462AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-010-A	Opening of the Fan Cowls 437AL(447AL),438AR(448AR)
TASK 74-21-41-200-010-A	Inspection of the Ignitor Plug
TASK 78-30-00-040-012-A	Deactivation of the Thrust Reverser Hydraulic Control Unit (HCU) for Ground Maintenance
TASK 78-32-00-010-010-A	Opening of the Thrust Reverser Halves
TSM 74-00-00-810-811	Failure of the Ignition System A on Engine 1
TSM 74-00-00-810-812	Failure of the Ignition System A on Engine 2
TSM 74-00-00-810-813	Failure of the Ignition System B on Engine 1
TSM 74-00-00-810-814	Failure of the Ignition System B on Engine 2
TSM 74-00-00-810-815	Failure of the Ignition Systems A and B on Engine 1
TSM 74-00-00-810-816	Failure of the Ignition Systems A and B on Engine 2
Igniter Plug
Clip Points

3. Job Set-up
Subtask 74-21-41-941-050-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 74-21-41-865-050-A ** ON A/C NOT FOR ALL

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	ENGINE/1 AND 2/IGN/SYS A	1JH	A03
FOR FIN: 1000EM1 (ENGINE1)
121VU	ENGINE/IGN/ENG1/SYS B	3JH1	P41
121VU	ENGINE/IGN/ENG1/SYS A BAT	2JH1	P39
FOR FIN: 1000EM2 (ENGINE2)
121VU	ENGINE/IGN/ENG2/SYS B	3JH2	P42
121VU	ENGINE/IGN/ENG2/SYS A BAT	2JH2	P40

Subtask 74-21-41-010-050-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Open the fan cowls (Ref. AMM TASK 71-13-00-010-010):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(2) Put the ACCESS PLATFORM 1M(3 FT) in position.

Subtask 74-21-41-040-050-A ** ON A/C NOT FOR ALL

D. Deactivate the thrust reverser Hydraulic Control Unit (HCU) (Ref. AMM TASK 78-30-00-040-012).

Subtask 74-21-41-010-054-A ** ON A/C NOT FOR ALL

E. Open the right thrust reverser half (Ref. AMM TASK 78-32-00-010-010):
(1) FOR [1000EM1] (ENGINE-1)
452AR
(2) FOR [1000EM2] (ENGINE-2)
462AR

4. Procedure
Subtask 74-21-41-020-050-A ** ON A/C NOT FOR ALL

A. Removal of the Igniter Plug (4001JH1,4001JH2)
(1) Disconnect the ignition lead.

Igniter Plug ** ON A/C NOT FOR ALL

Clip Points ** ON A/C NOT FOR ALL

(a) Loosen the clamps (2) and (6) and move them away from the cooling shrouds (1) and (5).
(b) Remove the cooling shrouds (1) and (5).
(c) Remove the bolt (10), the washer (9) and the clip (8) from the clip point at Detail C.
(d) Remove the bolt (18), the washers (19) and (23), the clips (20) and (22), the spacer (21) and the nut (24) from the clip point at Detail E.
(e) Remove the bolt (17), the washers (12) and (16), the clips (13) and (15), the spacer (14) and the nut (11) from the clip point at Detail D.
(f) Disconnect the ignition lead (4).
(g) Remove and discard the grommet (3) from the ignition lead (4).
(2) Remove the igniter plug.

Igniter Plug ** ON A/C NOT FOR ALL

NOTE: Replace igniter plug only if one or more of the following conditions are met:

A. Igniter plug not meeting wear limits per (Ref. AMM TASK 74-21-41-200-010) and/or,
B. Trouble Shooting Manual (TSM) findings for ignition faults per TSM 74-00-00-810-811, TSM 74-00-00-810-812, TSM 74-00-00-810-813, TSM 74-00-00-810-814 TSM 74-00-00-810-815 and/or TSM 74-00-00-810-816.

(a) Remove the lockwire from the igniter threaded insert.
(b) Hold the threaded insert with a wrench so it will not turn.
(c) Loosen the igniter plug (7) with a wrench to remove it from the threaded insert.
(d) Remove the igniter plug.
(e) Do the procedure again to remove the remaining igniter.
(3) Install COVER - PROTECTION to all exposed openings.

[Rev.10 from 2021] 2026.04.01 03:08:06 UTC