W DOC AIRBUS | AMM A320F

Installation of the Air/Oil Heat Exchanger (AOHX) [PW11]

TASK 79-21-11-400-802-A
Installation of the Air/Oil Heat Exchanger (AOHX)

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AFTER SHUTDOWN. THE ENGINE 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
FIN: 6002EM ** ON A/C NOT FOR ALL
1. Reason for the Job
Use this procedure to install the engine air/oil heat exchanger.
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
1
ACCESS PLATFORM 1M(3 FT)
No specific
1
STRAP-227 KG(500 LB),NYLON
No specific
1
TESTER SAFETY CABLE
No specific
Torque wrench: range to between 35 and 31.5 lbf.in (0.40 and 0.36 m.daN ) T
No specific
Torque wrench: range to between 44 and 38 lbf.in (0.50 and 0.43 m.daN ) T
No specific
Torque wrench: range to between 45 and 40 lbf.in (0.51 and 0.45 m.daN ) T
No specific
Torque wrench: range to between 100 and 90 lbf.in (1.13 and 1.02 m.daN ) T
No specific
Torque wrench: range to between 340 and 300 lbf.in (3.84 and 3.39 m.daN ) T
PWA211312
1
INSTALLATION FIXTURE
 B. Consumable Materials
REFERENCE
DESIGNATION
(Material No.P05-291)
cable, safety
(Material No.P05-292)
ferrule, safety cable
(Material No.P06-054)
compound, paste, anti-seize
(Material No.P09-014)
sealant, silicone rubber
(Material No.P11-014)
alcohol, isopropyl
 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. Expendable Parts
FIG.ITEM
DESIGNATION
IPC-CSN
35
SEAL
EIPC 79-21-11-01-080
35
SEAL
EIPC 79-21-11-01-090
 E. Referenced Information
REFERENCE
DESIGNATION
TASK 24-21-61-400-802-A
Installation of the Integrated Drive Generator (IDG) Power Feeder-Cables
TASK 24-21-61-400-803-A
Installation of the AC Generator Control-Harness
TASK 70-24-00-910-813-A
Assembly - PWA 316 - Safety Cable Installation
TASK 70-27-00-910-810-A
PWA 83 - Cleaning of Parts Before Adhesive Bonding, Sealing or Filling
TASK 71-00-00-720-811-A
Test No. 3A - Idle Power Test
TASK 71-00-00-860-832-A
Procedure to Prevent Engine Motoring and to Stop the Electrical Supply to the EEC
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 73-11-48-400-803-A
Installation of the Return Fuel Lines
TASK 73-21-69-400-802-A
Installation of the EEC Wiring Harness (WC10)
TASK 73-21-70-400-802-A
Installation of the Electronic Engine Control (EEC) Wiring Harness (WC11)
TASK 73-25-34-400-802-A
Installation of the Engine Interface Unit (EIU)
TASK 77-21-61-400-802-A
Installation of the Exhaust Gas Temperature (EGT) (T5/T3) Wiring Harness (WC05)
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
TASK 79-21-12-400-801-A
Installation of the Air/Oil Heat Exchange Bellows Seal
F Engine Air/Oil Heat Exchanger (AOHX) - (Assemble the Heat Exchanger)
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method One)
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two)
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two)
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two)
3. Job Set-up
Subtask 79-21-11-941-053-A ** ON A/C NOT FOR ALL
A. Safety Precautions
   (1) Make sure that you did the procedure to prevent engine motoring and to stop the electrical supply to the Electronic Engine Control (EEC)
(Ref. AMM TASK 71-00-00-860-832).
Subtask 79-21-11-010-056-A ** ON A/C NOT FOR ALL
B. Get Access
   (1) Make sure that the fan cowl doors are open (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) Make sure that the ACCESS PLATFORM 1M(3 FT) is in position.
Subtask 79-21-11-040-053-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) Make sure that you did the deactivation of the thrust reverser system for ground maintenance (Ref. AMM TASK 78-30-00-040-805).
Subtask 79-21-11-010-057-A ** ON A/C NOT FOR ALL
D. Get Access
   (1) Make sure that the thrust reverser cowl-doors are open (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 79-21-11-420-051-A ** ON A/C NOT FOR ALL
A. Installation of the AOHX
   (1) Removal of the protection covers:
CAUTION: REMOVE THE PROTECTION COVERS FROM THE OPENINGS AS NECESSARY TO PREVENT ENGINE DAMAGE.
     (a) Make sure that you remove all the necessary COVER - PROTECTION to prevent the damage to the engine.
   (2) Assemble the AOHX (18) on the workbench as follows:
F Engine Air/Oil Heat Exchanger (AOHX) - (Assemble the Heat Exchanger) ** ON A/C NOT FOR ALL
     (a) Attach the bracket (5) to the air-cooling exhaust duct (AD02) (4) with the two bolts (6). See sheet 1 of the figure:
F Engine Air/Oil Heat Exchanger (AOHX) - (Assemble the Heat Exchanger) ** ON A/C NOT FOR ALL
     (b) Attach the bracket (3) to the bracket (5) with the two bolts (8) and the two washers (7) and tighten with your fingers.
     (c) Attach the bracket (3) to the air-cooling exhaust duct (AD02) (4) with the two bolts (1) and the two washers (2) and tighten with your fingers.
     (d) TORQUE the two bolts (6) to between 44 and 38 lbf.in (0.50 and 0.43 m.daN ) T.
     (e) TORQUE the two bolts (1) to between 35 and 31.5 lbf.in (0.40 and 0.36 m.daN ) T.
     (f) TORQUE the two bolts (8) to between 35 and 31.5 lbf.in (0.40 and 0.36 m.daN ) T.
     (g) Clean the air-cooling exhaust duct (AD02) (4) by PWA 83 at the specified locations (Ref. AMM TASK 70-27-00-910-810). See sheets 2 and 3 of the figure:
F Engine Air/Oil Heat Exchanger (AOHX) - (Assemble the Heat Exchanger) ** ON A/C NOT FOR ALL
     (h) Wait ten minutes for the areas to dry if cleaned with the P11-014alcohol, isopropyl.
     (i) Apply the P09-014sealant, silicone rubber with the use of PWA 615 to the specified areas on the air-cooling exhaust duct (AD02) (4) (Ref. AMM D/O 70-24-00-91).
     (j) Attach the air-cooling exhaust duct (AD02) (4) to the AOHX (18) with the 14 bolts (24). See sheet 2 of the figure:
F Engine Air/Oil Heat Exchanger (AOHX) - (Assemble the Heat Exchanger) ** ON A/C NOT FOR ALL
     (k) TORQUE the 14 bolts (24) to between 100 and 90 lbf.in (1.13 and 1.02 m.daN ) T.
     (l) Clean off the unwanted P09-014sealant, silicone rubber from the air-cooling exhaust duct (AD02) (4) and the AOHX (18) seam.
     (m) Wait for the P09-014sealant, silicone rubber to cure (Ref. AMM D/O 70-24-00-91).
     (n) Clean the air-cooling intake duct (AD01) (19) by PWA 83 at the specified locations (Ref. AMM TASK 70-27-00-910-810). See sheets 2 and 3 of the figure:
F Engine Air/Oil Heat Exchanger (AOHX) - (Assemble the Heat Exchanger) ** ON A/C NOT FOR ALL
     (o) Wait ten minutes for the areas to dry if cleaned with the P11-014alcohol, isopropyl.
     (p) Apply the P09-014sealant, silicone rubber with the use of PWA 615 to the specified locations on the air-cooling intake duct (AD01) (19) (Ref. AMM D/O 70-24-00-91).
     (q) Attach the air-cooling intake duct (AD01) (19) to the AOHX (18) with the 12 bolts (20).
     (r) Attach the bracket (21) to the air-cooling intake duct (AD01) (19) with the three bolts (20).
     (s) TORQUE the 15 bolts (20) to between 100 and 90 lbf.in (1.13 and 1.02 m.daN ) T.
     (t) Clean off the unwanted P09-014sealant, silicone rubber from the air-cooling intake duct (AD01) (19) and the AOHX (18) seam.
     (u) Wait for the P09-014sealant, silicone rubber to cure (Ref. AMM D/O 70-24-00-91).
     (v) Install the bellows seal on the air-cooling exhaust duct (AD02) (4) if necessary (Ref. AMM TASK 79-21-12-400-801).
     (w) Attach the bracket (22) to the air-cooling exhaust duct (AD02) (4) with the four nuts (23).
     (x) TORQUE the four nuts (23) to between 45 and 40 lbf.in (0.51 and 0.45 m.daN ) T.
WARNING: BE CAREFUL WHEN YOU REMOVE/INSTALL THE AIR/OIL HEAT EXCHANGER ASSEMBLY FROM/ON THE ENGINE. THE AIR/OIL HEAT EXCHANGER IS HEAVY (APPROXIMATELY 75 LBS (34 KG)) AND IF IT FALLS, IT CAN CAUSE INJURY TO PERSONNEL OR DAMAGE TO THE ENGINE.
   (3) Install the AOHX assembly (34) (method one) as follows:
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method One) ** ON A/C NOT FOR ALL
CAUTION: INSTALL THE BOLTS FROM THE TOP. IF YOU DO NOT OBEY THIS INSTRUCTION, THE BOLTS WILL NOT BE CORRECTLY ATTACHED AND CAN FALL. THIS CAN ALSO CAUSE DAMAGE TO THE ENGINE PARTS.
     (a) Install the two bolts (52), the two bushings (41) and the two nuts (53) on the two connecting links and the AOHX assembly (34) and tighten with your fingers. See sheet 2 of the figure:
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method One) ** ON A/C NOT FOR ALL
       1 The AOHX assembly (34) must be installed to the upper rear connecting-link first.
     (b) Lift the AOHX assembly (34) to the highest position possible below the thrust reverser and then move the bottom of the AOHX inboard to align with the bracket assembly. See sheet 1 of the figure:
     (c) Install the bolt (40), bushing (41) and nut (39) on the bracket assembly and the AOHX assembly (34) and tighten with your fingers.
     (d) Install the bolt (51), bushing (41) and nut (39) on the bracket assembly and the AOHX assembly (34) and tighten with your fingers.
     (e) Install the two bolts (54) and the two washers (55) that attach the AOHX assembly (34) to the bracket.
     (f) TORQUE the two nuts (53) to between 340 and 300 lbf.in (3.84 and 3.39 m.daN ) T.
     (g) TORQUE the nut (39) to between 340 and 300 lbf.in (3.84 and 3.39 m.daN ) T.
     (h) TORQUE the two bolts (54) to between 35 and 31.5 lbf.in (0.40 and 0.36 m.daN ) T.
     (i) TORQUE the nut (39) to between 340 and 300 lbf.in (3.84 and 3.39 m.daN ) T.
WARNING: USE GOGGLES AND GLOVES WHEN YOU REMOVE OR INSTALL LOCKWIRE. EACH TIME YOU CUT LOCKWIRE, REMOVE AND DISCARD IT IMMEDIATELY. LOOSE LOCKWIRE CAN CUT YOU OR MAKE YOU BLIND, AND/OR CAN CAUSE DAMAGE.
     (j) Safety the bolt (51) with the P05-291cable, safety and the P05-292ferrule, safety cable and crimp the P05-292ferrule, safety cable with the TESTER SAFETY CABLE (Ref. AMM TASK 70-24-00-910-813).
   (4) Install the AOHX assembly (34) with the PWA211312 INSTALLATION FIXTURE (method two) as follows:
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
     (a) Remove the strap from the support table.
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
     (b) Attach the STRAP-227 KG(500 LB),NYLON to the AOHX assembly (34).
     (c) Attach the hoist to the STRAP-227 KG(500 LB),NYLON.
     (d) Remove the pin from the 1st post, move the head to the 2nd post and install the pin, if necessary. See sheet 2 of the figure:
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
     (e) Lift the AOHX assembly (34) with the hoist and put it in the PWA211312 INSTALLATION FIXTURE support table.
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
     (f) Install the strap on the support table and safety the AOHX assembly (34).
     (g) Use the tilt hand wheel to tilt the head until the support block is aligned with the flanges on the AOHX assembly (34).
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
     (h) Use the height hand wheel and the slide hand wheel to the position head until the support block against the AOHX assembly (34) flanges.
     (i) Loosen the four captive bolts to open the four clamps.
     (j) Align the four support block holes to the four flange bolts.
     (k) Tighten the four captive bolts to safety the four clamps to the AOHX assembly (34) flanges.
CAUTION: DO NOT MOVE THE AIR/OIL HEAT EXCHANGER WHEN IT IS IN THE UP POSITION. IF YOU DO NOT OBEY THIS CAUTION, DAMAGE TO THE PARTS CAN OCCUR.
CAUTION: WHEN YOU MOVE THE TOOL OR THE AIR/OIL HEAT EXCHANGER, BE CAREFUL NOT TO HIT THE ENGINE. IF YOU DO NOT OBEY THIS PRECAUTION, DAMAGE TO THE ENGINE OR PARTS CAN OCCUR.
     (l) Move the PWA211312 INSTALLATION FIXTURE from the aft of the engine under the left thrust reverser.
     (m) Use the foot brake to secure the PWA211312 INSTALLATION FIXTURE next to the engine.
     (n) Remove the strap from the support table and the AOHX assembly (34).
     (o) Use the height hand wheel to lift the AOHX assembly (34) off of the support block. See sheet 1 of the figure:
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
     (p) Remove the pin from the 2nd post, turn the head to the 1st post and install the pin. See sheet 2 of the figure:
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
     (q) Use the height hand wheel to lift the head to the highest position.
     (r) Use the height, slide and tilt hand wheels to align the AOHX assembly (34) with the two bracket assemblies and the two connecting links.
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
CAUTION: INSTALL THE BOLTS FROM THE TOP. IF YOU DO NOT OBEY THIS INSTRUCTION, THE BOLTS WILL NOT BE CORRECTLY ATTACHED AND CAN FALL. THIS CAN ALSO CAUSE DAMAGE TO THE ENGINE PARTS.
     (s) Install the two bolts (52), two bushings (41) and two nuts (53) on the two connecting links and the AOHX assembly (34) and tighten with your fingers. See sheet 2 of the figure:
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
       1 The AOHX assembly (34) must be installed to the upper rear connecting-link first.
     (t) Install the bolt (40), bushing (41) and nut (39) on the bracket assembly and the AOHX assembly (34) and tighten with your fingers. See sheet 1 of the figure:
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
     (u) Install the bolt (51), bushing (41) and nut (48) on the bracket assembly and the AOHX assembly (34) and tighten with your fingers.
     (v) Install the two bolts (54) and the two washers (55) that attach the AOHX assembly (34) to the bracket and tighten with your fingers.
     (w) TORQUE the two nuts (53) to between 340 and 300 lbf.in (3.84 and 3.39 m.daN ) T.
     (x) TORQUE the nut (39) to between 340 and 300 lbf.in (3.84 and 3.39 m.daN ) T.
     (y) TORQUE the nut (48) to between 340 and 300 lbf.in (3.84 and 3.39 m.daN ) T.
     (z) TORQUE the two bolts (54) to between 35 and 31.5 lbf.in (0.40 and 0.36 m.daN ) T.
WARNING: USE GOGGLES AND GLOVES WHEN YOU REMOVE OR INSTALL LOCKWIRE. EACH TIME YOU CUT LOCKWIRE, REMOVE AND DISCARD IT IMMEDIATELY. LOOSE LOCKWIRE CAN CUT YOU OR MAKE YOU BLIND, AND/OR CAN CAUSE DAMAGE.
     (aa) Safety the bolt (51) with the P05-291cable, safety and the P05-292ferrule, safety cable and crimp the P05-292ferrule, safety cable with the TESTER SAFETY CABLE. See sheet 2 of the figure:
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
     (ab) Loosen the four captive bolts to open the four clamps. See sheet 1 of the figure:
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
     (ac) Remove the four blocks from the AOHX assembly (34) flanges. See sheet 2 of the figure:
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
     (ad) Remove and lower the support block from the AOHX assembly (34) flanges with the height, tilt and slide wheels. See sheet 1 of the figure:
F Engine Air/Oil Heat Exchanger (AOHX) - (Installation Method Two) ** ON A/C NOT FOR ALL
     (ae) Disengage the brake on the PWA211312 INSTALLATION FIXTURE.
CAUTION: WHEN YOU MOVE THE TOOL OR THE AIR/OIL HEAT EXCHANGER, BE CAREFUL NOT TO HIT THE ENGINE. IF YOU DO NOT OBEY THIS PRECAUTION, DAMAGE TO THE ENGINE OR PARTS CAN OCCUR.
     (af) Remove the PWA211312 INSTALLATION FIXTURE aft of the engine.
   (5) Attach the tubes (LP57) and (LP56) to the AOHX assembly (34) as follows:
     (a) Apply the P06-054compound, paste, anti-seize to the threads of the six bolts (37).
       1 For the new or the refurbished bolts or the nuts with the baked-on lubricant, do not do the wet application.
     (b) Examine the current face seal (35) for reusability as follows:
       1 No raised material on the metal surface.
       2 Rubber that is not bonded to the seal plate is not permitted.
       3 Rubber that is missing is not permitted.
       4 Examine the rubber seal for separation from the seal plate.
       5 Rubber that is cut or damaged is not permitted.
       6 Make sure that the rubber material is above the metal surface.
     (c) Install the EIPC 79-21-11-01-080 SEAL (35) on the tube (LP56).
     (d) Attach the tube (LP56) and the bracket (38) to the AOHX assembly (34) with the three bolts (37).
NOTE: If the tube (LP56) was removed, the three bolts (37) that attach the tube (LP56) to the AOHX assembly (34) are shorter than the three bolts at the other end of the tube (LP56). Be sure to install the shorter bolts at the tube (LP56)/AOHX assembly (34) interface.
     (e) TORQUE the three bolts (37) to between 100 and 90 lbf.in (1.13 and 1.02 m.daN ) T equally in an opposite pattern until the same torque indication holds.
     (f) Examine the current face seal (35) for reusability as follows:
       1 No raised material on the metal surface.
       2 Rubber that is not bonded to the seal plate is not permitted.
       3 Rubber that is missing is not permitted.
       4 Examine the rubber seal for separation from the seal plate.
       5 Rubber that is cut or damaged is not permitted.
       6 Make sure that the rubber material is above the metal surface.
     (g) Install the EIPC 79-21-11-01-090 SEAL (35) on the tube (LP57).
     (h) Attach the tube (LP57) and the bracket (36) to the AOHX assembly (34) with three bolts (37).
       1 If the tube (LP57) was removed, the three bolts (37) that attach the tube (LP57) to the AOHX assembly (34) are shorter than the three bolts at the other end of the tube (LP57). Make sure that to install the shorter bolts at the tube (LP57)/AOHX assembly (34) interface.
     (i) TORQUE the three bolts (37) to between 100 and 90 lbf.in (1.13 and 1.02 m.daN ) T equally in an opposite pattern until the same torque indication holds.
   (6) Install the AC generator harness on the pylon interface panel as necessary (Ref. AMM TASK 24-21-61-400-803).
   (7) Install the Electronic Engine Control (EEC) wiring harness (WC10) on the engine as necessary (Ref. AMM TASK 73-21-69-400-802).
   (8) Install the EEC wiring harness (WC11) on the engine as necessary (Ref. AMM TASK 73-21-70-400-802).
   (9) Install the Exhaust Gas Temperature (EGT) wiring harness (WC05) on the engine as necessary (Ref. AMM TASK 77-21-61-400-802).
   (10) Install the Integrated Drive Generator (IDG) power feeder-cables on the engine as necessary (Ref. AMM TASK 24-21-61-400-802).
   (11) Install the Return To Tank (RTT) tube on the engine as necessary (Ref. AMM TASK 73-11-48-400-803).
5. Close-up
Subtask 79-21-11-410-051-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 79-21-11-440-051-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 79-21-11-410-050-A ** ON A/C NOT FOR ALL
C. Close Access
   (1) 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.
   (2) Remove the access platform(s).
   (3) Remove the WARNING NOTICE(S).
   (4) Make sure that all the circuit breakers shown in the paragraph Procedure of the engine interface unit installation are closed. If they are not, close them in the recommended sequence
(Ref. AMM TASK 73-25-34-400-802).
Subtask 79-21-11-720-051-A ** ON A/C NOT FOR ALL
D. Test
   (1) Do the idle power test (Ref. AMM TASK 71-00-00-720-811).
[Rev.10 from 2021] 2026.04.01 03:41:44 UTC
"Aviabrain" 2025