DOC AIRBUS | AMM A320FBorescope Inspection of Combustion Section and Fuel Nozzles [CFML]
TASK 72-40-00-290-801-A
Borescope Inspection of Combustion Section and Fuel Nozzles
Refer to the MPD TASK: 724000-L2
BORESCOPE INSPECTION OF COMBUSTION SECTION AND FUEL NOZZLES.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Consumable Materials
C. Work Zones and Access Panels
D. Referenced Information
3. Job Set-up
Subtask 72-40-00-941-051-A
Subtask 72-40-00-290-050-A Subtask 72-40-00-020-050-A
Subtask 72-40-00-410-052-A
[Rev.10 from 2021]
2026.04.01 13:03:41 UTC
Borescope Inspection of Combustion Section and Fuel Nozzles
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.
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
ZONE: 400
1. Reason for the JobRefer to the MPD TASK: 724000-L2
BORESCOPE INSPECTION OF COMBUSTION SECTION AND FUEL NOZZLES.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Consumable Materials
| REFERENCE | DESIGNATION |
|---|---|
| (Material No.CP2619) | Never Seez-Pure Nickel, Special |
| (Material No.CP2691) | penetrant |
| (Material No.CP2961) | tiodize T8E-H grease |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| 400 | POWER PLANT, NACELLES AND PYLONS |
| FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1) | |
| 437AL, 438AR, 451AL, 452AR | |
| FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2) | |
| 447AL, 448AR, 461AL, 462AR | |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 71-13-00-010-803-A | Opening of the Fan Cowl Doors |
| TASK 71-13-00-410-803-A | Closing of the Fan Cowl Doors |
| TASK 72-00-00-290-812-A | Engine Borescope Examination Preparation |
| TASK 74-21-10-000-802-A | Removal of the No. 1 (Left) Igniter |
| TASK 74-21-10-000-803-A | Removal of the No. 2 (Right) Igniter |
| TASK 74-21-10-210-801-A | Visual Inspection of the Igniter |
| TASK 74-21-10-400-802-A | Installation of the No. 1 (Left) Igniter |
| TASK 74-21-10-400-803-A | Installation of the No. 2 (right) Igniter |
| TASK 78-30-00-040-809-A | Deactivation of the Thrust Reverser System for Ground Maintenance |
| TASK 78-30-00-440-809-A | Reactivation of the Thrust Reverser System after Ground Maintenance |
| TASK 78-36-00-010-806-A | Opening of the Thrust Reverser Cowl Doors |
| TASK 78-36-00-410-806-A | Closing of the Thrust Reverser Cowl Doors |
Combustion Section Borescope Port LocationsSubtask 72-40-00-941-051-A
A. 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 the WARNING NOTICE(S) in position to tell persons not to operate:
(a) Make sure that the ON legend of the FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put the WARNING NOTICE(S) in position to tell persons not to energize FADEC 1(2).
Subtask 72-40-00-010-052-A (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 the WARNING NOTICE(S) in position to tell persons not to operate:
- The ENG/MODE selector switch, and
- The ENG/MASTER 1(2) control switch.
(a) Make sure that the ON legend of the FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put the WARNING NOTICE(S) in position to tell persons not to energize FADEC 1(2).
B. 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.
Subtask 72-40-00-040-051-A (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.
C. Deactivation of the Thrust Reverser System for Maintenance
Subtask 72-40-00-010-053-A 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 maintenance (Ref. AMM TASK 78-30-00-040-809). D. Open the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-010-806):
(1) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR
(2) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
461AL 462AR.
(3) Put an ACCESS PLATFORM 1M(3 FT) in position.
4. Procedure(1) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR
(2) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
461AL 462AR.
(3) Put an ACCESS PLATFORM 1M(3 FT) in position.
Subtask 72-40-00-290-050-A Subtask 72-40-00-020-050-A
B. Do further preparation as follows:
(1) Remove the borescope plugs from ports N and Q.
(b) Let it soak.
(c) Apply a break torque with the WRENCH - STANDARD to remove the borescope plug from the case.
(d) Apply spray of penetrant (Material No.CP2691) again to lubricate the borescope plug thread, if necessary.
(e) Continue to remove the borescope plug.
(f) Put an identification tag on each borescope plug.
(g) For any borescope plugs not removed (N or Q), do a check as follows:
1 Do a visual check to make sure that the anti-rotation sleeve of the locking ring is fully engaged with one of the two slots on the borescope boss, on the borescope inspection port.
2 Make sure that the borescope plug is fully installed against the case.
3 Use the BORESCOPE DIA 3.8 MM (0.15 IN) to check the condition of the borescope plugs, if there is no direct visual access.
4 Apply hand pressure to the borescope plug in the removal direction to check for loose plugs.
5 If the borescope plug is loose, apply correct torque value again. Refer to paragraph 4.E.
(2) Remove no. 1 (left) igniter (Ref. AMM TASK 74-21-10-000-802):
(3) Remove no. 2 (right) igniter (Ref. AMM TASK 74-21-10-000-803):
(a) Put an identification tag on no. 2 (right) igniter.
(4) Insert the BORESCOPE DIA 3.8 MM (0.15 IN) (or alternate) into its position for the inspection.
Subtask 72-40-00-290-051-A (1) Remove the borescope plugs from ports N and Q.
NOTE: Only remove the plugs necessary for inspection.
(a) Apply spray of penetrant (Material No.CP2691) on the ratcheting mechanism. (b) Let it soak.
(c) Apply a break torque with the WRENCH - STANDARD to remove the borescope plug from the case.
(d) Apply spray of penetrant (Material No.CP2691) again to lubricate the borescope plug thread, if necessary.
(e) Continue to remove the borescope plug.
(f) Put an identification tag on each borescope plug.
(g) For any borescope plugs not removed (N or Q), do a check as follows:
1 Do a visual check to make sure that the anti-rotation sleeve of the locking ring is fully engaged with one of the two slots on the borescope boss, on the borescope inspection port.
2 Make sure that the borescope plug is fully installed against the case.
3 Use the BORESCOPE DIA 3.8 MM (0.15 IN) to check the condition of the borescope plugs, if there is no direct visual access.
4 Apply hand pressure to the borescope plug in the removal direction to check for loose plugs.
5 If the borescope plug is loose, apply correct torque value again. Refer to paragraph 4.E.
(2) Remove no. 1 (left) igniter (Ref. AMM TASK 74-21-10-000-802):
NOTE: Removal of no. 1 (left) and no. 2 (right) igniters may not be necessary if you use flexible borescope inspection equipment. Remove the igniters if you find something that you cannot examine through the borescope inspection ports N and Q.
(a) Put an identification tag on no. 1 (left) igniter. (3) Remove no. 2 (right) igniter (Ref. AMM TASK 74-21-10-000-803):
(a) Put an identification tag on no. 2 (right) igniter.
(4) Insert the BORESCOPE DIA 3.8 MM (0.15 IN) (or alternate) into its position for the inspection.
C. Combustor / High Pressure Turbine (HPT) Section Inspection
(1) Table 601 identifies how many fuel nozzles, HPT stage 1 nozzle airfoils and deflector plates there are for the combustion section and HPT stage 1 nozzle.
(2) Do an inspection of:
Subtask 72-40-00-080-050-A (1) Table 601 identifies how many fuel nozzles, HPT stage 1 nozzle airfoils and deflector plates there are for the combustion section and HPT stage 1 nozzle.
| Table 601: |
| Component | Quantity |
|---|---|
| Fuel nozzles | 19 |
| Stage 1 HPT nozzle airfoils | 36 |
| Combustion section deflector plates | 19 |
| INSPECTION/CHECK | MAXIMUM SERVICEABLE LIMITS | REMARKS |
|---|---|---|
| 1.Do an examination of the surfaces of the combustor, fuel nozzles aft heat shield and stage 1 nozzle leading edge as follows: | | |
| (a) Discoloration | Discoloration is permitted. | |
| (b) Carbon accumulation | Any amount of carbon deposit is permitted. | |
| (c) Missing, chipped or spalled areas of the Thermal Barrier Coating (TBC) | Any amount of missing, chipped or spalled areas of TBC is permitted. | |
| 2. Examine the deflectors and the dome plate (if it is visible) as follows: (Sheet 1, Sheet 3 and Sheet 4). | | |
| (a) Distortion of the deflector | Any amount permitted. | |
| (b) Axial or radial cracks in the deflector (View F) | There is no limit to the number of cracks permitted in these conditions:
| |
| (c) Over-serviceable limit extension for axial or radial cracks in the deflector | Cracks longer than the serviceable limit are permitted for 25 cycles. | This over-serviceable limit extension is for a one-time continue-in-service application. |
| (d) Circumferential cracks in the deflector (View F) | No cracks are permitted. | |
| (e) Missing deflector material (View F) | Missing material is permitted on the deflector as long as the maximum depth of missing material does not exceed 0.100 in. (2.54 mm) per deflector from the edge (first row of cooling holes fully visible). | There are a total of 19 deflectors. |
| (f) Over-serviceable limit extension for missing deflector material | Missing material more than the serviceable limits is permitted for 25 cycles. | This over-serviceable limit extension is for a one-time continue-in-service application. |
| (g) Radial dome plate cracks (View F) | There is no limit to the number of radial cracks permitted in these conditions:
| |
| (h) Over-serviceable limit extension for radial dome plate cracks (View F) | Radial cracks between 0.20 in. (5.08 mm) and 0.40 in. (10.16 mm) in length. | |
| | The cracks are not connected. | |
| | The cracks that have a separation of minimum 2.0 in. (50.80 mm) and cracks from the innermost cooling holes of each domeplate are permitted for 25 cycles. | This over-serviceable limit extension is for a one-time continue-in-service application. |
| (i) Circumferential dome plate cracks (View F) | No circumferential cracks are permitted. | |
| (j) Over-serviceable limit extension circumferential dome plate cracks (View F) | Circumferential cracks up to 0.40 in. (10.16 mm), not connected, with 2.0 in. (50.80 mm) minimum separation are permitted for 25 cycles. | This over-serviceable limit extension is for a one-time continue-in-service application. |
| 3. Examine the combustion chamber mixer trailing edge as follows: (see Sheet 3, Sheet 4 and Sheet 5). | | |
| (a) Oxidation or missing material (View G and Section A-A) | In Area X up to 0.05 in. (1.27 mm) of missing material permitted from the trailing edge, limited to 270 degrees in the circumferential direction (at any clocking position). | |
| (b) Over-serviceable limit extension for oxidation or missing material | Missing material in Area Y no more than 0.10 in. (2.54 mm) from Area X is permitted for 25 cycles. | This over-serviceable limit extension is for a one-time continue-in-service application. |
| 4. Examine the fuel nozzles as follows: (see Sheet 1, Sheet 3, Sheet 4 and Sheet 6) | | |
| (a) Heat shield (aft surface) for (View J): | | |
| Any amount of discoloration or carbon deposit is permitted. | |
| Any amount of radial cracks is permitted up to 0.10 in. (2.54 mm) long from the outer edge are permitted. | |
| | Up to eight radial cracks are permitted for the full length of the aft surface. | |
| No circumferential cracking is permitted. | |
| Up to 0.050 in. (1.27 mm) permitted at the outer diameter for 360 degrees. | A CUP is defined as a location for a dome deflector plate and fuel nozzle. There are 19 cups in a combustor assembly. |
| | | Cooling holes in the second row can be partially visible with this amount of oxidation or missing material. |
| From 0.050 in. (1.27 mm) to 0.075 in. (1.90 mm) 360 degrees permitted at the outer diameter for 25 cycles. | Cooling holes in the second row can be fully visible with this amount of oxidation or missing material. |
| (b) Heat shield sharp lip for (View G + Section B-B): | | |
| Up to two areas of oxidation or missing material permitted for up to 0.30 in. (7.62 mm) of circumferential length each (any amount of depth). Distressed areas should be located at least 0.30 in. (7.62 mm) from each other. | |
| Oxidation or missing material 0.30 in. (7.62 mm) of circumferential length in up to three locations is permitted for 25 cycles. | This over-serviceable limit extension is for a one-time continue-in-service application. |
| Any amount of discoloration or carbon deposit is permitted. | |
| (c) Heat shield conic surface and splitter for (View G + Section B-B): | | |
| Any amount of discoloration or carbon deposit is permitted. | |
| Any amount of axial cracks are permitted up to 0.23 in. (5.84 mm) length (entire length of the heat shield component). | |
| Any amount of axial cracks are permitted. | |
| No circumferential cracking is permitted. | |
| No oxidation or missing material is permitted on conic surface. | |
| 0.050 in. (1.27 mm) of oxidation or missing material for 360 degrees permitted on conic surface trailing edge. | |
| Oxidation or missing material between 0.050 in. (1.27 mm) and 0.075 in. (1.90 mm) for 360 degrees is permitted for 25 cycles. | This over-serviceable limit extension is for a one-time continue-in-service application. |
| 5. Examine the combustion inner liners as follows: (See Sheet 1 and Sheet 2). | | |
| (a) Circumferential cracks | There is no limit for the number of cracks permitted with this condition:
| |
| (b) Over-serviceable limit extension for circumferential cracks | Cracks between 0.5 in. (12.70 mm) and 1.0 in. (25.40 mm) in length are permitted for 25 cycles. | This over-serviceable limit extension is for a one-time continue-in-service application. |
| (c) Axial or diagonal cracks | There is no limit to the number of cracks with this condition.
| |
| (d) Over-serviceable limit extension for axial or diagonal cracks | Cracks between 0.5 in. (12.70 mm) and 1.0 in. (25.40 mm) in length are permitted for 250 cycles. | This over-serviceable limit extension is for a reduced interval, repeat inspection. |
| | Cracks between 1.0 in. (25.40 mm) and 1.5 in. (38.10 mm) in length are permitted for 100 cycles. | |
| | Cracks between 1.5 in. (38.10 mm) and 2.0 in. (50.80 mm) in length are permitted for 50 cycles. | |
| | Cracks between 2.0 in. (50.80 mm) and 2.252 in. (57.20 mm) in length are permitted for 25 cycles. | This over-serviceable limit extension is for a one-time continue-in-service application. |
| (e) Axial, diagonal and circumferential connected cracks | Connected cracks are permitted if the combined crack length is less than the limit of paragraph (5).(b) and 5.(d). To find the total length of connected cracks, measure from the most forward crack edge to the most aft crack edge. Connected cracks in the same cooling hole row are not added. Areas fully enclosed by connecting cracks must be 0.385 in.2 (248.39 mm2) or less. | NOTE: C-I-S limits of paragraphs 5.(b) and 5.(d) apply also for length of connected cracks. |
| (f) Over-serviceable limit extension for axial, diagonal and circumferential connected cracks. | Connected cracks area that is more than the serviceable limit is permitted for 25 cycles. Combined crack length is less than 25 cycles C-I-S limit of paragraphs 5.(b) and 5.(d). | This over-serviceable limit extension is for a one-time continue-in-service application. |
| (g) Burn through or missing metal | Burn through or missing metal areas are permitted with these conditions:
| |
| (h) Over-serviceable limit extension for burn through or missing metal | Burn through or missing metal that is more than the serviceable limit is permitted for 25 cycles. | This over-serviceable limit extension is for a one-time continue-in-service application. |
| (i) Distortion | Distortion is permitted with this condition:
| |
| (j) Over-serviceable limit extension for distortion | Distortion between 0.5 in. (12.70 mm) and 0.75 in. (19.05 mm) is permitted for 25 cycles. | This over-serviceable limit extension is for a one-time continue-in-service application. |
| 6. Examine the outer combustion liners as follows: (see Sheet 1 and 2). | | |
| (a) Circumferential cracks | There is no limit to the number of cracks with this condition:
| |
| (b) Over-serviceable limit extension for circumferential cracks | Cracks between 0.5 in. (12.70 mm) and 1.0 in. (25.40 mm) length are permitted for 25 cycles. | This over-serviceable limit extension is for a one-time continue-in-service application. |
| (c) Axial or diagonal cracks | There is no limit to the number of cracks with this condition:
| |
| (d) Over-serviceable limit extension for axial or diagonal cracks | Cracks between 0.5 in. (12.70 mm) and 1.0 in. (25.40 mm) in length are permitted for 250 cycles. | This over-serviceable limit extension is for a reduced interval, repeat inspection. |
| | Cracks between 1.0 in. (25.40 mm) and 1.5 in. (38.10 mm) in length are permitted for 100 cycles. | |
| | Cracks between 1.5 in. (38.10 mm) and 2.0 in. (50.80 mm) in length are permitted for 50 cycles. | |
| | Cracks between 2.0 in. (50.80 mm) and 2.252 in. (57.20 mm) in length are permitted for 25 cycles | This over-serviceable limit extension is for a one-time continue-in-service application. |
| (e) Axial, diagonal and circumferential connected cracks | Connected cracks are permitted if the combined crack length is less than the limit of paragraph 6.(b) and 6.(d). To find the total length of connected cracks, measure from the most forward crack edge to the most aft crack edge. Connected cracks in the same cooling hole row are not added. Areas fully enclosed by connecting cracks are to be 0.385 in.2 (248.39 mm2) or less. | NOTE: C-I-S limits of paragraphs 6.(b) and 6.(d) apply also for length of connected cracks. |
| (f) Over-serviceable limit extension for axial, diagonal and circumferential connected cracks. | Connected cracks area that is more than the serviceable limit is permitted for 25 cycles. Combined crack length is less than 25 cycles C-I-S limit of paragraphs 6.(b) and 6.(d). | This over-serviceable limit extension is for a one-time continue-in-service application. |
| (g) Burn through or missing metal | Burn through or missing metal are permitted with these conditions: | |
| | A maximum permitted area for the nugget is not more than 0.01 in.2 (6.45 mm2). | |
| | Total permitted burn through area on the outer liner is less than 0.385 in.2 (248.39 mm2). | |
| (h) Over-serviceable limit extension for burn through or missing metal | Burn through or missing metal that is more than the serviceable limit is permitted for 25 cycles. | This over-serviceable limit extension is for a one-time continue-in-service application. |
| (i) Distortion | Distortion is permitted with this condition:
| |
| (j) Over-serviceable limit extension for distortion | Distortion between 0.5 in. (12.70 mm) and 0.75 in. (19.05 mm) is permitted for 25 cycles. | This over-serviceable limit extension is for a one-time continue-in-service application. |
| 7. Examine the leading edge of the HPT stage 1 nozzle airfoil as follows: | | |
| (a) Missing TBC | There is no limit to the quantity of TBC that can be missing. | |
| (b) Cracks that connect nose holes | There is no limit to the number permitted if:
| |
| (c) Cracks that extend from a nose hole(s) but do not connect with another nose hole(s): | There is no limit to the number permitted if no metal is missing. | |
| (d) Burns or erosion (the surface is burned and no holes through the parent metal): | The total damage is less than 0.175 in. (4.44 mm) in diameter for each vane. | |
| | There are no more than two burned vanes in a 90 degree arc. | |
| (e) Over-serviceable limit extension for HPT stage 1 nozzle leading edge | | |
| 1_ Leading edge metal that is missing because of cracks or burn through | As much as 0.14 in.2 (90.32 mm2) for each airfoil with a maximum of two vanes in a 90 degree arc is permitted for 25 cycles. | This over-serviceable limit extension is for a one-time Continue -In-Service application. |
D. When the inspection is completed, remove the BORESCOPE DIA 3.8 MM (0.15 IN) (or alternate).
Subtask 72-40-00-420-050-A E. Install the borescope plugs and igniters in ports N, Q, O and P as follows:
(2) Remove the identification tags from the borescope plugs N and Q before the installation of each borescope plug.
(3) Apply layer of tiodize T8E-H grease (Material No.CP2961) to the threads, pressure faces and ratcheting mechanism.
.
(6) After the borescope plug is installed:
(a) Do a check of the borescope plug:
1 Do a visual check of the borescope plug and make sure that the anti-rotation sleeve or sleeves are fully engaged with the slots on the borescope boss.
2 Do a check to make sure that the head of the borescope plug is fully installed against the borescope boss.
(b) If one or two of these conditions are not met, the ratcheting feature of the plug can be seized or locked. Do the steps that follow:
1 Apply penetrant (Material No.CP2691) directly in between the locking ring and the head of the borescope plug.
2 Apply torque again to the plug until the plug begins to rotate freely.
3 TORQUE the borescope plug to between 113 and 97 lbf.in (1.28 and 1.10 m.daN ).
(c) Do a visual check again, before you continue:
1 Do a visual check of the borescope plug and make sure that the anti-rotation sleeve or sleeves are fully engaged with the slots on the borescope boss.
2 Do a check to make sure that the head of the borescope plug is fully installed against the borescope boss.
(d) If above conditions cannot be met, replace the borescope plug.
(e) Use the BORESCOPE DIA 3.8 MM (0.15 IN) to check the condition of the borescope plug, if there is no direct visual access.
(7) If the igniters are removed, install them as follows:
(a) Do a visual inspection of the igniters and the igniter ports O and P (Ref. AMM TASK 72-00-00-290-812) and (Ref. AMM TASK 74-21-10-210-801).
(b) Remove the identification tags from the igniters before the installation of each igniter.
(c) Install no. 1 (left) igniter in the igniter port P (Ref. AMM TASK 74-21-10-400-802).
(d) Install no. 2 (right) igniter in the igniter port O (Ref. AMM TASK 74-21-10-400-803).
(e) TORQUE the igniter plugs to between 307 and 262 lbf.in (3.47 and 2.96 m.daN ).
5. Close-upNOTE: When you install the borescope plug, make sure that the anti-rotation sleeve or sleeves on the borescope plug are correctly engaged with the slots on the borescope boss before you fully tighten the plug.
(1) Do a visual inspection of the borescope plugs and the borescope ports N and Q (Ref. AMM TASK 72-00-00-290-812). (2) Remove the identification tags from the borescope plugs N and Q before the installation of each borescope plug.
(3) Apply layer of tiodize T8E-H grease (Material No.CP2961) to the threads, pressure faces and ratcheting mechanism.
NOTE: You can use CP2619 Never Seez-Pure Nickel, Special
(4) Install the borescope plugs in the combustor borescope ports N and Q. NOTE: The use of penetrant (Material No.CP2691) sprayed into the ratcheting mechanism is allowed to release it. This should be done before you replace the borescope plug.
(5) TORQUE the borescope plugs to between 113 and 97 lbf.in (1.28 and 1.10 m.daN ) . (6) After the borescope plug is installed:
(a) Do a check of the borescope plug:
1 Do a visual check of the borescope plug and make sure that the anti-rotation sleeve or sleeves are fully engaged with the slots on the borescope boss.
2 Do a check to make sure that the head of the borescope plug is fully installed against the borescope boss.
(b) If one or two of these conditions are not met, the ratcheting feature of the plug can be seized or locked. Do the steps that follow:
1 Apply penetrant (Material No.CP2691) directly in between the locking ring and the head of the borescope plug.
2 Apply torque again to the plug until the plug begins to rotate freely.
3 TORQUE the borescope plug to between 113 and 97 lbf.in (1.28 and 1.10 m.daN )
. (c) Do a visual check again, before you continue:
1 Do a visual check of the borescope plug and make sure that the anti-rotation sleeve or sleeves are fully engaged with the slots on the borescope boss.
2 Do a check to make sure that the head of the borescope plug is fully installed against the borescope boss.
(d) If above conditions cannot be met, replace the borescope plug.
(e) Use the BORESCOPE DIA 3.8 MM (0.15 IN) to check the condition of the borescope plug, if there is no direct visual access.
(7) If the igniters are removed, install them as follows:
(a) Do a visual inspection of the igniters and the igniter ports O and P (Ref. AMM TASK 72-00-00-290-812) and (Ref. AMM TASK 74-21-10-210-801).
(b) Remove the identification tags from the igniters before the installation of each igniter.
(c) Install no. 1 (left) igniter in the igniter port P (Ref. AMM TASK 74-21-10-400-802).
(d) Install no. 2 (right) igniter in the igniter port O (Ref. AMM TASK 74-21-10-400-803).
(e) TORQUE the igniter plugs to between 307 and 262 lbf.in (3.47 and 2.96 m.daN )
. Subtask 72-40-00-410-052-A
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 78-36-00-410-806):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
461AL 462AR.
Subtask 72-40-00-440-051-A Subtask 72-40-00-410-053-A (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 78-36-00-410-806):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
461AL 462AR.