W DOC AIRBUS | AMM A320F

Replacement of the Diffuser Case Insert and Spacer [PW11]

TASK 72-41-01-920-803-A
Replacement of the Diffuser Case Insert and Spacer

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AND THE ADJACENT COMPONENTS AFTER ENGINE SHUTDOWN. THE ENGINE, THE ENGINE OIL AND THE ADJACENT COMPONENTS CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS INSTRUCTION, INJURY CAN OCCUR.
WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
ZONE: 400
1. Reason for the Job
Use this procedure to replace igniter A or B insert if damaged and to measure for the correct spacer to make sure that the igniters have the proper immersion into the diffuser case.
For more information about the ignition system, refer to 74-00-00 CONF 21 - IGNITION - GENERAL - DESCRIPTION AND OPERATION.
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
1
CRIMPING TOOL BERGEN C10-148
No specific
Torque wrench: range to between 470 and 400 lbf.in (5.31 and 4.52 m.daN ) T
PWA104199
1
GAGE IMMERSION
PWA26657
1
TAP CHASING DIFFUSER CASE SPARK IGNITER THREAD
 B. Consumable Materials
REFERENCE
DESIGNATION
(Material No.P05-291)
cable, safety
(Material No.P06-054)
compound, paste, anti-seize
 C. Work Zones and Access Panels
ZONE/ACCESS
ZONE DESCRIPTION
400
POWER PLANT, NACELLES AND PYLONS
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR, 451AL, 452AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR, 461AL, 462AR
 D. Referenced Information
REFERENCE
DESIGNATION
TASK 71-00-00-860-833-A
Procedure to Prevent Engine Motoring
TASK 71-13-00-010-802-A
Opening of the Fan Cowl Doors
TASK 71-13-00-410-802-A
Closing of the Fan Cowl Doors
TASK 72-41-01-300-801-A
Repair of the Igniter Boss Chase Thread on the Outer Diffuser Case Assembly
TASK 74-21-01-000-801-A
Removal of the Igniter Plug
TASK 74-21-01-400-801-A
Installation of the Igniter Plug
TASK 78-30-00-040-805-A
Deactivation of the Thrust Reverser System for Ground Maintenance
TASK 78-30-00-440-805-A
Reactivation of the Thrust Reverser System after Ground Maintenance
TASK 78-36-00-010-802-A
Opening of the Thrust Reverser Cowl-Doors
TASK 78-36-00-410-802-A
Closing of the Thrust Reverser Cowl-Doors
F Diffuser Case Insert and Spacer
3. Job Set-up
Subtask 72-41-01-941-051-A ** ON A/C NOT FOR ALL
A. Safety Precautions
   (1) Do the procedure to prevent engine motoring
(Ref. AMM TASK 71-00-00-860-833).
Subtask 72-41-01-010-052-A ** ON A/C NOT FOR ALL
B. Get Access
   (1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-802):
     (a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR.
     (b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR.
   (2) Put the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position.
Subtask 72-41-01-040-051-A ** ON A/C NOT FOR ALL
C. Deactivation of the Thrust Reverser for Ground Maintenance
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 of the thrust reverser system for ground maintenance (Ref. AMM TASK 78-30-00-040-805).
Subtask 72-41-01-010-053-A ** ON A/C NOT FOR ALL
D. Get Access
   (1) Open the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-010-802):
     (a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
451AL, 452AR.
     (b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
461AL, 462AR.
4. Procedure
CAUTION: WIPE CLEAN ALL PARTS AND TOOLS AS NECESSARY TO REMOVE UNWANTED DEBRIS AND PREVENT DAMAGE TO THE ENGINE.
Subtask 72-41-01-920-051-A ** ON A/C NOT FOR ALL
A. Replacement of the Diffuser Case Insert and Spacer
   (1) Remove the igniter plug(s), if necessary (Ref. AMM TASK 74-21-01-000-801).
   (2) Remove the igniter plug insert(s) (2) and spacer(s) (1). See the sheet 1 of the figure:
F Diffuser Case Insert and Spacer ** ON A/C NOT FOR ALL
   (3) Use the PWA26657 TAP CHASING DIFFUSER CASE SPARK IGNITER THREAD to clean the diffuser case threads, if necessary (Ref. AMM TASK 72-41-01-300-801).
   (4) Install the two igniter boss inserts (2) on the diffuser case assembly as follows. See the sheets 1 and 2 of the figure:
F Diffuser Case Insert and Spacer ** ON A/C NOT FOR ALL
     (a) Apply P06-054compound, paste, anti-seize on the threads of the two igniter boss inserts (3).
       1 For new or refurbished hardware with baked-on lubricant, do not do the wet application.
     (b) Install the two igniter boss inserts (2) without the two spacers (1) on the diffuser case fingertight.
     (c) Do an immersion measurement. Find the distance between each igniter boss insert (2) and the combustion chamber inner diameter surface as follows. See the sheets 2 and 3 of the figure:
F Diffuser Case Insert and Spacer ** ON A/C NOT FOR ALL
       1 Set the PWA104199 GAGE IMMERSION extension to 3.250 in. (82.550 mm).
       2 Insert the PWA104199 GAGE IMMERSION through the insert (2) and into the combustion chamber.
NOTE: The PWA104199 GAGE IMMERSION must not have the hook pointed in the aft direction.
       3 Make sure that the hook of the PWA104199 GAGE IMMERSION points forward and the bung is held tightly against the insert (2).
       4 Pull the center of the PWA104199 GAGE IMMERSION out until the hook touches the combustion chamber inner diameter and pressure is applied to the guide plate.
       5 Make sure that the hook tip is against the combustion chamber surface.
       6 Read the PWA104199 GAGE IMMERSION and record as Dimension A.
     (d) Calculate the spacer (1) thickness required as follows:
       1 Subtract Dimension A from 2.787 in. (70.790 mm) and record the results as Dimension B.
       2 Use Dimension B to determine the actual spacer class. See table 1.
NOTE: The spacer nominal thickness should be closest to Dimension B.
NOTE: Multiple spacers can be stacked, if required.
       3 Measure the spacer (1) thickness at four locations, record the average thickness as Dimension C.
       4 If the sum of Dimensions A and C is not between 2.777 in. (70.536 mm) and 2.797 in. (71.044 mm), select another spacer (1) with the use of step 4.A.(4)(b).
Class
Inches
Millimeters
1
0.038 - 0.048
0.966 - 1.219
2
0.048 - 0.058
1.219 - 1.473
3
0.058 - 0.068
1.474 - 1.727
4
0.068 - 0.078
1.728 - 1.981
5
0.078 - 0.088
1.982 - 2.235
6
0.088 - 0.098
2.236 - 2.489
7
0.098 - 0.108
2.489 - 2.743
8
0.108 - 0.118
2.744 - 2.997
9
0.118 - 0.128
2.998 - 3.251
10
0.128 - 0.138
3.252 - 3.505
11
0.138 - 0.148
3.506 - 3.759
12
0.148 - 0.158
3.759 - 4.013
13
0.158 - 0.168
4.014 - 4.267
14
0.168 - 0.178
4.268 - 4.521
15
0.178 - 0.188
4.522 - 4.775
16
0.008 - 0.018
0.204 - 0.457
17
0.018 - 0.028
0.458 - 0.711
18
0.028 - 0.038
0.712 - 0.965
Table - Spacer thickness (Dimension C)
     (e) Remove the two inserts (2).
     (f) Install the two inserts (2) with spacers (1) on the diffuser case assembly fingertight.
CAUTION: MAKE SURE THAT THE DIFFUSER CASE INSERTS ARE TORQUED TO THE SPECIFIED TORQUE. IF THEY ARE NOT, YOU CAN APPLY TOO MUCH TORQUE WHEN YOU INSTALL THE IGNITER PLUGS. THIS WILL CAUSE AN INCORRECT TORQUE OF THE INSERTS OR IGNITER PLUGS, WHICH CAN CAUSE UNWANTED REMOVAL OF THE INSERTS AT THE NEXT PLUG REMOVAL.
     (g) TORQUE the two inserts (2) to between 470 and 400 lbf.in (5.31 and 4.52 m.daN ) T.
     (h) Do an immersion measurement. Find the distance between each igniter boss insert (2) and the combustion chamber inner diameter surface as follows. See the sheets 2 and 4 of the figure:
F Diffuser Case Insert and Spacer ** ON A/C NOT FOR ALL
       1 Set the igniter installation PWA104199 GAGE IMMERSION extension to 3.250 in. (82.550 mm).
       2 Insert the PWA104199 GAGE IMMERSION through the insert (2) and into the combustion chamber.
NOTE: The PWA104199 GAGE IMMERSION must not have the hook pointed in the aft direction.
       3 Make sure that the hook of the PWA104199 GAGE IMMERSION points forward and the bung is held tightly against the insert (2).
       4 Pull the center of the PWA104199 GAGE IMMERSION out until the hook touches the combustion chamber inner diameter and pressure is applied to the guide plate.
       5 Make sure that the hook tip is against the combustion chamber surface.
       6 Read the PWA104199 GAGE IMMERSION and record as Dimension D.
       7 Dimension D must be between 2.777 in. (70.536 mm) and 2.797 in. (71.044 mm).
       8 If the measurement is not between 2.777 in. (70.536 mm) and 2.797 in. (71.044 mm), remove the insert(s) (2) and the spacer(s) (1), examine the parts for correct interface and repeat step 4.A.(4)(f).
     (i) Safety the two inserts (2) to the fuel nozzle bolt closest to each insert (2) with P05-291cable, safety and crimp with the CRIMPING TOOL BERGEN C10-148.
   (5) Install the igniter plug(s) (Ref. AMM TASK 74-21-01-400-801).
   (6) Examine the assembly for foreign objects, damage and correct assembly.
5. Close-up
Subtask 72-41-01-410-052-A ** ON A/C NOT FOR ALL
A. Close Access
   (1) Make sure that the work area is clean and clear of tools and other items.
   (2) Close the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-410-802):
     (a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
451AL, 452AR.
     (b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
461AL, 462AR.
Subtask 72-41-01-440-051-A ** ON A/C NOT FOR ALL
B. Do the reactivation of the thrust reverser system after ground maintenance (Ref. AMM TASK 78-30-00-440-805).
Subtask 72-41-01-410-053-A ** ON A/C NOT FOR ALL
C. Close Access
   (1) Remove the access platform(s).
   (2) Make sure that the work area is clean and clear of tools and other items.
   (3) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-802):
     (a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR.
     (b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR.
   (4) Remove the WARNING NOTICE(S).
[Rev.10 from 2021] 2026.04.01 13:03:17 UTC
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