Repair the Fan Case Rear Acoustic Liner [PW11]

TASK 72-21-01-320-803-A
Repair the Fan Case Rear Acoustic Liner

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.

WARNING: YOU MUST USE A CORRECT EYE PROTECTION WHEN YOU PERFORM THIS PROCEDURE. IF YOU DO NOT OBEY THIS WARNING, INJURY CAN OCCUR.

ZONE: 400

1. Reason for the Job
Use this procedure to repair the damage on the rear acoustic liner.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	GUN - SEALANT
No specific	1	KNIFE - PUTTY
No specific	1	MACHINE - DRILLING, PORTABLE
No specific	1	PLIERS - THIN NOSE
No specific	1	VACUUM CLEANER
636-1100-3GSE	1	INLET COWL PROTECT COVER

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.P05-146)	abrasive paper, silicon carbide
(Material No.P05-253)	paper, abrasive
(Material No.P05-260)	spatula, acrylic or fiber
(Material No.P05-274)	paper, abrasive
(Material No.P05-437)	tape, pressure sensitive polyester
(Material No.P05-493)	tape, non-silicone adhesive, polyester
(Material No.P08-016)	adhesive paste, epoxy, non-thixotropic
(Material No.P08-025)	adhesive paste, epoxy, thixotropic
(Material No.P11-065)	acetone
(Material No.P11-078)	alcohol, isopropyl

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
400	POWER PLANT, NACELLES AND PYLONS

D. Referenced Information

REFERENCE	DESIGNATION
TASK 70-27-00-910-804-A	SPOP 208 - Degreasing of Parts by Solvent Wiping
TASK 71-00-00-860-833-A	Procedure to Prevent Engine Motoring
TASK 72-11-03-000-801-A	Removal of the Fan Blades
TASK 72-11-03-400-801-A	Installation of the Fan Blades
Fan Case Assembly Rear Acoustic Liner Repair

3. Job Set-up
Subtask 72-21-01-941-066-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).
(2) Put an 636-1100-3GSE INLET COWL PROTECT COVER inside the engine intake cowl and fan case inside surfaces.
(3) If you cannot get access to the repair area, remove a minimum number of fan blades as necessary to accomplish this repair (Ref. AMM TASK 72-11-03-000-801).

4. Procedure

CAUTION: WIPE CLEAN ALL PARTS AND TOOLS AS NECESSARY TO REMOVE UNWANTED DEBRIS AND PREVENT DAMAGE TO THE ENGINE.

Subtask 72-21-01-350-053-A ** ON A/C NOT FOR ALL

A. Repair of the Fan Case Rear Acoustic Liner
(1) Use the P05-146abrasive paper, silicon carbide, P05-253paper, abrasive or the P05-274paper, abrasive to remove delaminated layers and any frayed material around a crack, tear or puncture of the rear acoustic liner. It is permissible to trim to remove large areas of frayed or delaminated liner, but precautions are required to not score the intact layers underneath:
(a) Remove any loose or torn or foreign material in punctured areas.
(b) It is permissible to straighten honeycomb with PLIERS - THIN NOSE or equivalent to facilitate the removal of debris and provide visual access to the case wall surface underneath.
(c) Remove all material extending into the flow path.
(d) No damage to the case wall is permitted.
(2) Visually examine the repair area. If the inner surface of the fan case is damaged follow the disposition per the visual inspection section. Perform a tap test to verify that the disbond did not extend past the repair area. Reject any disbond.
(3) Clean the repair area by SPOP 208. Use the P11-078alcohol, isopropyl or the acetone (Material No.P11-065) (Ref. AMM TASK 70-27-00-910-804):
(a) Flush the repair area before wiping. Mask outside the repair area to ensure that the solvent does not contaminate the engine.
(b) Allow the surface to air-dry at 60 deg.F (15.56 deg.C) to 90 deg.F (32.22 deg.C) for a minimum of 15 minutes.
(4) Use P05-146abrasive paper, silicon carbide, P05-253paper, abrasive or P05-274paper, abrasive to abrade the repair area on the rear acoustic liner to make the damage smooth and remove any contamination. Ensure that debris does not contaminate the engine. Remove all remaining debris with a VACUUM CLEANER.
(5) Clean the repair area by SPOP 208. Use the P11-078alcohol, isopropyl or the acetone (Material No.P11-065) and allow the surface to air-dry at 60 deg.F (15.56 deg.C) to 90 deg.F (32.22 deg.C) for a minimum of 15 minutes (Ref. AMM TASK 70-27-00-910-804).
(6) Mask the rear acoustic liner treatment outside of the repair area to prevent the adhesives and dust from blocking the acoustic treatment with the P05-437tape, pressure sensitive polyester or the P05-493tape, non-silicone adhesive, polyester.
(7) Fill the repair area per PWA 615 using the P08-016adhesive paste, epoxy, non-thixotropic or the P08-025adhesive paste, epoxy, thixotropic, except the repair may occur in a clean area as follows:

CAUTION: MAKE SURE THAT:

THERE ARE NO UNCURED PAINTS, UNCURED EPOXY, OILS, POWDER, FUMES, DUST AND OTHER DEBRIS ON THE REPAIR AREA
THERE IS NO CONTAMINATION ON THE MATERIALS, TOOLINGS, FIXTURES AND HANDLING EQUIPMENT USED.

CONTAMINATION OF THE REPAIR AREA, THE MATERIALS AND/OR THE EQUIPMENT WILL HAVE AN UNWANTED EFFECT ON THE BONDING, SEALING AND FILLING QUALITY. IF YOU DO NOT OBEY THIS CAUTION, SEAL SEPARATION AND LOSS OF BOND CAN OCCUR.

(a) Mix the repair material in the following proportions, step 4.A.(7)(a)1_ or step 4.A.(7)(a)2_.
1 P08-016adhesive paste, epoxy, non-thixotropic part A 100 parts to part B 33 parts.
2 P08-025adhesive paste, epoxy, thixotropic part A 100 parts to part B 17 parts.

NOTE: These mixtures have a 60 minutes life after mixing.

(b) Fill the honeycomb cells in the damaged area and a minimum of one full cell beyond the damaged area by using the GUN - SEALANT. Make smooth the filler surface with the KNIFE - PUTTY or a P05-260spatula, acrylic or fiber:
1 If necessary, it is permitted to increase the size of the liner perforations in the rear acoustic liner by using the MACHINE - DRILLING, PORTABLE.
2 The compound, when applied, must come through the liner perforations adjacent to the hole being filled.
(c) Ensure that the filler material is retained in the repair location.
(d) Cure the adhesive, refer to step 4.A.(7)(d)1_ or step 4.A.(7)(d)2_ :
1 4 hours minimum at 60 deg.F (15.56 deg.C) to 90 deg.F (32.22 deg.C) followed by 1.5 hour minimum at 140 deg.F (60.00 deg.C) to 160 deg.F (71.11 deg.C).
2 24 hours minimum at 60 deg.F (15.56 deg.C) to 90 deg.F (32.22 deg.C).
(e) Remove the masking tape after a minimum of 4 hours cure time.
(8) After the filler material is cured for a minimum of 4 hours at 60 deg.F (15.56 deg.C) to 90 deg.F (32.22 deg.C), remove the excess filler materials to the adjacent contour with a P05-146abrasive paper, silicon carbide, P05-253paper, abrasive, P05-274paper, abrasive or equivalent. Ensure that the transition from the repair to non-repair area is smooth and continuous.
(9) Clean the repair area by SPOP 208. Use the P11-078alcohol, isopropyl or the acetone (Material No.P11-065) and allow the surface to air-dry at 60 deg.F (15.56 deg.C) to 90 deg.F (32.22 deg.C) for a minimum of 15 minutes (Ref. AMM TASK 70-27-00-910-804).
(10) Visually examine the repair area to ensure that all damage has been repaired.
(11) Use a VACUUM CLEANER to remove chips and debris, paying particular attention to the bottom of the fan case.
(12) Clean the repair area by SPOP 208. Use the P11-078alcohol, isopropyl or the acetone (Material No.P11-065) (Ref. AMM TASK 70-27-00-910-804).
(13) Examine the assembly for foreign object damage and correct assembly.

5. Close-up
Subtask 72-21-01-860-058-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Install any removed fan blades as necessary (Ref. AMM TASK 72-11-03-400-801).
(2) Remove the 636-1100-3GSE INLET COWL PROTECT COVER from the air intake cowl.

[Rev.10 from 2021] 2026.04.01 13:02:31 UTC