General Visual Inspection (GVI) of the Engine and Pylon Drain System [PW11]
TASK 71-71-00-210-801-A
General Visual Inspection (GVI) of the Engine and Pylon Drain System
Use this procedure to visually inspect the engine and pylon drain system external parts for damage (nicks, dents, pitting, corrosion and scratches), correct attachment, correct clearance and leakage.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Work Zones and Access Panels
C. Referenced Information
3. Job Set-up
Subtask 71-71-00-941-051-A ** ON A/C NOT FOR ALL
Subtask 71-71-00-210-050-A ** ON A/C NOT FOR ALL
Subtask 71-71-00-410-052-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.01 02:33:51 UTC
General Visual Inspection (GVI) of the Engine and Pylon Drain System
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.
CAUTION:
YOU MUST ADJUST ALL TUBES WITH LESS THAN 0.125 INCH (3.175 MM) CLEARANCE TO ADJACENT TUBES OR PARTS. TUBES WITH LESS CLEARANCE CAN CHAFE DURING ENGINE OPERATION. THIS CAN CAUSE A LEAK AND A POSSIBLE IN-FLIGHT SHUTDOWN.
ZONE: 400
1. Reason for the JobUse this procedure to visually inspect the engine and pylon drain system external parts for damage (nicks, dents, pitting, corrosion and scratches), correct attachment, correct clearance and leakage.
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 | CLOTH-CROCUS |
| 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 | |
| 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 72-21-08-000-801-A | Removal of the Fan Exit Liner Segments |
| TASK 72-21-08-400-801-A | Installation of the Fan Exit Liner Segments |
| 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 |
Subtask 71-71-00-941-051-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 71-71-00-010-052-A ** ON A/C NOT FOR ALL (1) Do the procedure to prevent engine motoring
(Ref. AMM TASK 71-00-00-860-833).
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 an ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position.
Subtask 71-71-00-040-051-A ** ON A/C NOT FOR ALL (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 an ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position.
C. Deactivation of the Thrust Reverser for Maintenance
Subtask 71-71-00-010-053-A ** ON A/C NOT FOR ALL 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 78-30-00-040-805). 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
(2) Remove the fan exit liner segment a 6 o'clock location (Ref. AMM TASK 72-21-08-000-801) to get access to FB01 tube.
4. Procedure(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
(2) Remove the fan exit liner segment a 6 o'clock location (Ref. AMM TASK 72-21-08-000-801) to get access to FB01 tube.
Subtask 71-71-00-210-050-A ** ON A/C NOT FOR ALL
A. General Visual Inspection (GVI) of the Engine and Pylon Drain System
(1) Do a visual inspection of the engine and pylon drain tubes to make sure that there is a 0.125 in. (3.17 mm) minimum clearance with the adjacent tubes or parts. If the clearance is less than 0.125 in. (3.17 mm), do the steps that follow:
(a) Loosen all the clamp bolts and/or brackets at all the support points along the tube length.
(b) Loosen all the tube fittings.
(c) Adjust the tube and clamps to get the 0.125 in. (3.17 mm) minimum clearance with the adjacent tubes or parts.
(d) Tighten all the clamp bolts and/or brackets.
(e) Tighten all the tube fittings.
(f) Check the tubes that were adjusted for leaks.
(2) Do a visual inspection of the engine pylon and drain tubes to make sure that they are attached correctly at all the support locations as follows:
(a) Replace all the worn or damaged clamps.
(b) Tighten all the loose clamp bolts and/or brackets at all the support points along the tube length.
(c) Tighten all the loose tube fittings.
(3) Do a visual inspection of the engine and pylon drain system tube connections for leaks and loose connections as follows:
(a) Examine the tube-to-tube connections.
(b) Examine the tube or manifold-to-component connections.
(c) Examine the tube-to-boss connections.
(d) No leaks or loose connections are permitted.
Table 1 - Inspect the Engine and Pylon Drain System
(4) Examine the assembly for foreign objects, damage and correct assembly.
5. Close-up(1) Do a visual inspection of the engine and pylon drain tubes to make sure that there is a 0.125 in. (3.17 mm) minimum clearance with the adjacent tubes or parts. If the clearance is less than 0.125 in. (3.17 mm), do the steps that follow:
(a) Loosen all the clamp bolts and/or brackets at all the support points along the tube length.
(b) Loosen all the tube fittings.
(c) Adjust the tube and clamps to get the 0.125 in. (3.17 mm) minimum clearance with the adjacent tubes or parts.
(d) Tighten all the clamp bolts and/or brackets.
(e) Tighten all the tube fittings.
(f) Check the tubes that were adjusted for leaks.
(2) Do a visual inspection of the engine pylon and drain tubes to make sure that they are attached correctly at all the support locations as follows:
(a) Replace all the worn or damaged clamps.
(b) Tighten all the loose clamp bolts and/or brackets at all the support points along the tube length.
(c) Tighten all the loose tube fittings.
(3) Do a visual inspection of the engine and pylon drain system tube connections for leaks and loose connections as follows:
(a) Examine the tube-to-tube connections.
(b) Examine the tube or manifold-to-component connections.
(c) Examine the tube-to-boss connections.
(d) No leaks or loose connections are permitted.
Table 1 - Inspect the Engine and Pylon Drain System
| EXAMINE | DAMAGE | DISPOSITION |
|---|---|---|
| Engine and pylon drain system tubes and drain hose assemblies (does not include the fire sleeves) for: | | |
| Cracks | All quantities, all locations | Not permitted. Replace the tube. |
| Corrosion and stains | All quantities, all locations | Permitted, if it can be removed by light polish with a CLOTH-CROCUS. |
| | Heavy corrosion that can not be removed by light polish | Not permitted. Replace the tube. |
| Nicks, scratches, chafing and pits | All quantities 0.002 in. (0.05 mm) maximum depth, all locations | Permitted |
| | All quantities more than the permitted limits | Not permitted. Replace the tube. |
| Dents | All dents that do not have sharp edges or corners | Permitted if the tube Outer Diameter (OD) is not decreased by more than ten percent at each location. |
| | All dents that have sharp edges or corners | Not permitted. Replace the tube. |
| | Dents located 0.250 in. (6.35 mm) or less from the ferrule | Not permitted. Replace the tube. |
| Correct attachment at all support locations | All worn, damaged or loose clamps, all locations | Not permitted. Replace all worn or damaged clamps, tighten all loose clamps, all loose attachment bolts and nuts for the full length of the tube or hose. |
| Fuel system tubes, drain hose assembly connections, case boss connections and components for: | | |
| Loose connections | All quantities, all locations | Not permitted. Tighten all loose connections as necessary. |
| Leaks | All quantities, all locations | Not permitted. Tighten the loose tube nut or replace the tube or hose. |
| Engine and pylon drain hose assembly fire sleeves for: | | |
| Cracks and heat blisters | All quantities, all locations | Not permitted. Replace the tube assembly. |
| Exposure to fire or too much heat that is indicated by wire or fitting discoloration, pitting or distortion | All quantities, all locations | Not permitted. Replace the tube assembly. |
| Damage to the white fiberglass braid | All quantities, all locations | Not permitted. Replace the tube assembly. |
| Gouge damage | A 0.030 in. (0.76 mm) maximum depth, 1.0 in.2 (645.16 mm2) maximum area and does not damage the white fiberglass braid | Permitted |
| Cut or tear damage | A 0.250 in.2 (161.29 mm2) maximum area and does not damage the white fiberglass braid | Permitted |
| Flap damage | A 1.0 in. (25.40 mm) maximum for each side for a maximum of three sides and does not damage the white fiberglass braid | Permitted |
| Slit damage | A 3.0 in. (76.20 mm) maximum axially or 0.250 in. (6.35 mm) maximum perpendicular to the hose axis and does not cause damage to the white fiberglass braid | Permitted |
Subtask 71-71-00-410-052-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) Install the fan exit liner segment at 6 o'clock location (Ref. AMM TASK 72-21-08-400-801).
(3) 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 71-71-00-440-051-A ** ON A/C NOT FOR ALL (1) Make sure that the work area is clean and clear of tools and other items.
(2) Install the fan exit liner segment at 6 o'clock location (Ref. AMM TASK 72-21-08-400-801).
(3) 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
B. Do the reactivation of the thrust reverser system after maintenance (Ref. AMM TASK 78-30-00-440-805).
Subtask 71-71-00-410-053-A ** ON A/C NOT FOR ALL
Engine and Pylon Drain System