DOC AIRBUS | AMM A320FInstallation of the Forward Engine Mount System [CFMI]
TASK 71-21-11-400-040-A
Installation of the Forward Engine Mount System
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Consumable Materials
C. Referenced Information
3. Job Set-up
Subtask 71-21-11-860-050-A ** ON A/C NOT FOR ALL 4. Procedure
Subtask 71-21-11-420-055-A ** ON A/C NOT FOR ALL
Subtask 71-21-11-410-054-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.01 12:54:55 UTC
Installation of the Forward Engine Mount System
CAUTION:
THIS PART IS A REMOVABLE STRUCTURAL COMPONENT (RSC), WHICH CAN BE MOVED BETWEEN AIRCRAFT. THUS IT CAN HAVE DIFFERENT OPERATION CONDITIONS AND A DIFFERENT LIFE RECORD (FLIGHT HOURS/FLIGHT CYCLES/CALENDAR) FROM THE AIRCRAFT IT IS INSTALLED ON OR REMOVED FROM. THE OPERATOR IS RESPONSIBLE FOR THE SPECIFIC TRACKING AND CONTINUED AIRWORTHINESS OF REMOVABLE STRUCTURAL COMPONENTS. INCORRECT MAINTENANCE OF THESE COMPONENTS CAN CAUSE A RISK FOR THE FLIGHT SAFETY.
1. Reason for the JobSelf explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Consumable Materials
| REFERENCE | DESIGNATION |
|---|---|
| (Material No.CP1041) | isopropyl alcohol |
| (Material No.CP2215) | primer |
| (Material No.CP2541) | sealant RTV 88 |
| (Material No.CP8002) | lockwire 0.032 in. (0.8 mm) dia |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 71-00-00-000-040-A | Removal of the Power Plant |
| TASK 71-00-00-000-040-A-01 | Removal of the Power Plant with the Engine Positioner TWW 75E |
| TASK 71-00-00-000-040-A-03 | Removal of the Power Plant with Jacxson Tool |
| TASK 71-00-00-400-040-A | Installation of the Power Plant |
| TASK 71-00-00-400-040-A-01 | Installation of the Power Plant with the Engine Positioner TWW 75E |
| TASK 71-00-00-400-040-A-03 | Installation of the Power Plant with Jacxson Tool |
Forward Engine MountSubtask 71-21-11-860-050-A ** ON A/C NOT FOR ALL 4. Procedure
Subtask 71-21-11-420-055-A ** ON A/C NOT FOR ALL
A. Installation of the Forward Engine Mount System
(1) Install the support assemblies (75) on the engine flange.
(b) Install the support assemblies (75) on the engine flange with the shear pins (80), washers (100, 105, 110), and bolts (85, 90, 95).
(c) Torque the bolts (85 and 90) to between 228 and 168 lbf.in (2.58 and 1.90 m.daN )
.
(d) Torque the bolts (95) to between 816 and 744 lbf.in (9.22 and 8.41 m.daN ).
(e) Safety the bolts (85, 90, 95) withCP8002 lockwire 0.032 in. (0.8 mm) dia
(2) Connect the forward engine mount to the engine flange.
(a) Remove the rubber shipping washers.
(d) Connect the forward engine mount to the engine flange with the washers (60) and bolts (50).
(e) Torque the bolts (50) to between 348 and 336 lbf.in (3.93 and 3.80 m.daN ).
(f) Safety the bolts (50) withCP8002 lockwire 0.032 in. (0.8 mm) dia
(3) Connect the forward engine mount to the support assemblies (75).
(b) Check the locking feature of the nuts (45).
1 Install the nut (45) on the bolt (35) by hand until you can no longer turn the nut (45). Make sure the nut (45) is correctly installed on the bolt (35).
2 With a torque wrench, tighten the nut (45) until at least three threads of the bolt (35) extend from the nut (45). If the force required to tighten the nut (45) is greater than 80.0 lbf.in (0.90 m.daN), you must replace the nut (45).
3 With at least three threads of the bolt (35) extended from the nut (45), use a torque wrench to apply force to the nut (45) in the removal direction until the nut (45) begins to move. If the force required to start the nut (45) is less than 9.5 lbf.in (0.11 m.daN), you must replace the nut (45).
(d) Allow the primer (Material No.CP2215) to fully cure. Refer to the manufacturer's instructions.
1 Hold the nuts (45 or 47) while you torque the bolts (35) to the minimum torque of 260.0 lb-in. (2,93 m.daN). Do not allow the wings of the retainers (30) or the wings of the nuts (47) to contact the sides of the link assemblies (70).
2 Hold the nuts (45 or 47) and continue to torque the bolts (35) until the bolt holes in the retainers (25) align with the bolt holes in the retainers (30) when you put the retainers (25) over the heads of the bolts (35). Do not exceed the maximum torque of 320.0 lbf.in (3.62 m.daN). Do not allow the wings of the retainers (30) or the wings of the nuts (47) to contact the sides of the link assemblies (70).
(h) Check the locking feature of the nuts (20).
1 Install the nut (20) on the bolt (5) by hand until you can no longer turn the nut (20). Make sure the nut (20) is correctly installed on the bolt (5).
2 With a torque wrench, tighten the nut (20) until at least three threads of the bolt (5) extend from the nut (20). If the force required to tighten the nut (20) is greater than 18.0 lbf.in (0.20 m.daN), you must replace the nut (20).
3 With at least three threads of the bolt (5) extended from the nut (20), use a torque wrench to apply force to the nut (20) in the removal direction until the nut (20) begins to move. If the force required to start the nut (20) is less than 2.0 lbf.in (0.02 m.daN), you must replace the nut (20).
(i) Connect the retainers (25) to the retainers (30) with the washers (10 and 15), bolts (5), and nuts (20).
(j) Torque the nuts (20) to between 25 and 20 lbf.in (0.28 and 0.23 m.daN ).
(k) Apply sealant RTV 88 (Material No.CP2541) RTV 88 to the engine mount system.
2 Remove any temporary shims and fill the space between the wings on the nuts (47) and the link assemblies (70) with sealant RTV 88 (Material No.CP2541) RTV 88. Refer to the manufacturer's instructions.
3 Apply a bead of sealant RTV 88 (Material No.CP2541) RTV 88 around the head of the bolts (35). Make sure the sealant RTV 88 (Material No.CP2541) RTV 88 fills any gaps between the retainers (25) and the heads of the bolts (35). Refer to the manufacturer's instructions.
4 Allow the sealant RTV 88 (Material No.CP2541) to fully cure. Refer to the manufacturer's instructions.
5. Close-up(1) Install the support assemblies (75) on the engine flange.
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(a) Clean the support assemblies (75), attaching hardware, and engine mount flange with a cloth made moist with isopropyl alcohol (Material No.CP1041) . Then clean the surface with a clean, dry cotton cloth before the solvent dries. (b) Install the support assemblies (75) on the engine flange with the shear pins (80), washers (100, 105, 110), and bolts (85, 90, 95).
(c) Torque the bolts (85 and 90) to between 228 and 168 lbf.in (2.58 and 1.90 m.daN )
. (d) Torque the bolts (95) to between 816 and 744 lbf.in (9.22 and 8.41 m.daN )
. (e) Safety the bolts (85, 90, 95) with
(2) Connect the forward engine mount to the engine flange.
(a) Remove the rubber shipping washers.
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(b) Clean the forward end of the forward engine mount, attaching hardware, and engine flange with a cloth made moist with isopropyl alcohol (Material No.CP1041) . Then clean the surface with a clean, dry cotton cloth before the solvent dries. WARNING:
THE FORWARD ENGINE MOUNT WEIGHS APPROXIMATELY 60.0 POUNDS (27,27 KG). MAKE SURE THAT YOU SAFELY SUPPORT THE FORWARD ENGINE MOUNT AND KEEP IT AWAY FROM OTHER ENGINE COMPONENTS. IF YOU DO NOT OBEY THIS INSTRUCTION, INJURY TO MAINTENANCE PERSONNEL AND/OR DAMAGE TO EQUIPMENT CAN OCCUR.
(c) Put the forward engine mount into position on the engine. Safely support the forward engine mount and keep it away from other engine components. (d) Connect the forward engine mount to the engine flange with the washers (60) and bolts (50).
(e) Torque the bolts (50) to between 348 and 336 lbf.in (3.93 and 3.80 m.daN )
. (f) Safety the bolts (50) with
(3) Connect the forward engine mount to the support assemblies (75).
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(a) Clean the link assemblies (70), attaching hardware, and support assemblies (75) with a cloth made moist with isopropyl alcohol (Material No.CP1041) . Then clean the surface with a clean, dry cotton cloth before the solvent dries. (b) Check the locking feature of the nuts (45).
1 Install the nut (45) on the bolt (35) by hand until you can no longer turn the nut (45). Make sure the nut (45) is correctly installed on the bolt (35).
2 With a torque wrench, tighten the nut (45) until at least three threads of the bolt (35) extend from the nut (45). If the force required to tighten the nut (45) is greater than 80.0 lbf.in (0.90 m.daN), you must replace the nut (45).
3 With at least three threads of the bolt (35) extended from the nut (45), use a torque wrench to apply force to the nut (45) in the removal direction until the nut (45) begins to move. If the force required to start the nut (45) is less than 9.5 lbf.in (0.11 m.daN), you must replace the nut (45).
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(c) Apply primer (Material No.CP2215) to the surfaces of the following components where you will apply sealant RTV 88 (Material No.CP2541) RTV 88: the retainers (25 and 30), link assemblies (70), washers (40), nuts (47), and heads of the bolts (35). Refer to the manufacturer's instructions. (d) Allow the primer (Material No.CP2215) to fully cure. Refer to the manufacturer's instructions.
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
(e) Apply sealant RTV 88 (Material No.CP2541) RTV 88 to the surfaces of the washers (40) and the retainers (30) that interface with the link assemblies (70). CAUTION:
THE WINGS OF THE RETAINERS (30) AND WINGS OF THE NUTS (47) CAN DAMAGE THE SIDES OF THE LINK ASSEMBLIES (70). DO NOT ALLOW THE WINGS OF THE RETAINERS (30) AND WINGS OF THE NUTS (47) TO CONTACT THE SIDES OF THE LINK ASSEMBLIES (70).
CAUTION:
MAKE SURE YOU INSTALL THE SLIP FIT BUSHINGS (65).
(f) Before the sealant RTV 88 (Material No.CP2541) hardens, connect the link assemblies (70) to the support assemblies (75) with the bushings (65), bolts (35), washers (40), nuts (45 or 47), and retainers (30). Do not allow the wings of the retainers (30) or the wings of the nuts (47) to contact the sides of the link assemblies (70). Do not torque the bolts (35) at this time. NOTE: You can put temporary wooden shims between the wings of the retainers (30) and wings of the nuts (47) and the sides of the link assemblies (70) to protect the link assemblies (70) while you torque the bolts (35).
(g) Torque the bolts (35). 1 Hold the nuts (45 or 47) while you torque the bolts (35) to the minimum torque of 260.0 lb-in. (2,93 m.daN). Do not allow the wings of the retainers (30) or the wings of the nuts (47) to contact the sides of the link assemblies (70).
2 Hold the nuts (45 or 47) and continue to torque the bolts (35) until the bolt holes in the retainers (25) align with the bolt holes in the retainers (30) when you put the retainers (25) over the heads of the bolts (35). Do not exceed the maximum torque of 320.0 lbf.in (3.62 m.daN). Do not allow the wings of the retainers (30) or the wings of the nuts (47) to contact the sides of the link assemblies (70).
(h) Check the locking feature of the nuts (20).
1 Install the nut (20) on the bolt (5) by hand until you can no longer turn the nut (20). Make sure the nut (20) is correctly installed on the bolt (5).
2 With a torque wrench, tighten the nut (20) until at least three threads of the bolt (5) extend from the nut (20). If the force required to tighten the nut (20) is greater than 18.0 lbf.in (0.20 m.daN), you must replace the nut (20).
3 With at least three threads of the bolt (5) extended from the nut (20), use a torque wrench to apply force to the nut (20) in the removal direction until the nut (20) begins to move. If the force required to start the nut (20) is less than 2.0 lbf.in (0.02 m.daN), you must replace the nut (20).
(i) Connect the retainers (25) to the retainers (30) with the washers (10 and 15), bolts (5), and nuts (20).
(j) Torque the nuts (20) to between 25 and 20 lbf.in (0.28 and 0.23 m.daN )
. (k) Apply sealant RTV 88 (Material No.CP2541) RTV 88 to the engine mount system.
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
CAUTION:
BE CAREFUL WITH THE WINGS OF THE RETAINERS (30) AND WINGS OF THE NUTS (47). THEY CAN CAUSE DAMAGE TO THE SIDES OF THE LINK ASSEMBLIES (70). THE RTV 88 MAKES A CUSHION BETWEEN THE COMPONENTS AND KEEPS THE BOLTS (35) TIGHT.
1 Remove any temporary shims and fill the space between the retainers (25 and 30) and the link assemblies (70) with sealant RTV 88 (Material No.CP2541) RTV 88. Refer to the manufacturer's instructions. 2 Remove any temporary shims and fill the space between the wings on the nuts (47) and the link assemblies (70) with sealant RTV 88 (Material No.CP2541) RTV 88. Refer to the manufacturer's instructions.
3 Apply a bead of sealant RTV 88 (Material No.CP2541) RTV 88 around the head of the bolts (35). Make sure the sealant RTV 88 (Material No.CP2541) RTV 88 fills any gaps between the retainers (25) and the heads of the bolts (35). Refer to the manufacturer's instructions.
4 Allow the sealant RTV 88 (Material No.CP2541) to fully cure. Refer to the manufacturer's instructions.
Subtask 71-21-11-410-054-A ** ON A/C NOT FOR ALL