W DOC AIRBUS | TSM A320F

Fan Vibrations Higher than or Equal to 4 Units and less than 6 Units on Engine 1 or 2

TASK 77-00-00-810-863-A
Fan Vibrations Higher than or Equal to 4 Units and less than 6 Units on Engine 1 or 2

1. Possible Causes
  • wiring, connectors and receptacles
  • SENSOR-NO. 1 BRG VIB [4002EV]
  • TRF vibration sensor
  • EVMU
  • fan blades
  • LPT Stage 4 blades
  • fan blades mid-span shrouds
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
AR
BRUSH - BRISTLED
No specific
AR
PLIERS - NOSE, SOFT, LONG
 B. Consumable Materials
REFERENCE
DESIGNATION
(Material No.CP2011)
stoddard solvent
 C. Referenced Information
REFERENCE
DESIGNATION
AMM 71-00-00-750-001
Fan Trim Balance - 1 Sensor 3 Speed
AMM 72-21-00-210-004
Detailed Inspection and Relubrication of Fan Blade Dovetails, Midspan Shrouds, Retainers, Spacers, Dampers and Fan Disk Dovetail Slots
AMM 72-21-00-210-009
Inspection of Fan Rotor Blades Installed on the Fan Disk
AMM 72-21-00-210-025
Inspect Fan Rotor Blades Installed on the Fan Disk
AMM 72-54-00-290-002
Inspection of the Stage 4 Blades
AMM 72-54-00-290-006
Inspection of the Stage 4 Blades
AMM 73-21-50-210-001
Visual Inspection of the Wiring Harness
AMM 73-21-50-210-002
Visual Inspection of the Wiring Harnesses
AMM 77-31-10-720-001
Electrical Test of the No. 1 Bearing Vibration Sensor
AMM 77-31-10-720-002
Electrical Test of the No. 1 Bearing Vibration Sensor
AMM 77-31-30-000-001
Removal of the Turbine Rear Frame Vibration Sensor
AMM 77-31-30-000-002
Removal of the Turbine Rear Frame Vibration Sensor
AMM 77-31-30-400-001
Installation of the Turbine Rear Frame Vibration Sensor
AMM 77-31-30-400-002
Installation of the Turbine Rear Frame Vibration Sensor
ASM 773202
AMM 77-32-34-710-040
Operational Check of EVMU through CFDS for Advisory Indication on ECAM
3. Fault Confirmation
Subtask 77-00-00-710-151-A ** ON A/C NOT FOR ALL
A. Test
   (1) Not applicable, the fault is evident.
4. Fault Isolation
Subtask 77-00-00-810-120-A ** ON A/C NOT FOR ALL
A. If the fault symptom is identified on the lower ECAM display unit by the crew observation: ENG 1(2)-FAN VIBRATION higher than or equal to 4 units and less than 6 units:
NOTE: Trouble Shooting is recommended at next maintenance opportunity not interfering with Revenue Service operation.
   (1) do the following checks if no aircraft structure vibration/rumble was reported by the crew.
NOTE: If momentary vibration on ECAM is greater than 4 units but in order of less than 1 minute, no maintenance action is required provided indication is no associated with aircraft vibration felt by the crew and the indication did not repeat during the flight or following flights.
     (a) Do a check of the wiring, connectors and receptacles between ASM 773202:
  • The No. 1 vibration sensor (4002EV) to the EVMU (2EV)
  • The TRF vibration sensor (4003EV) to the EVMU (2EV).
     (b) Check for damaged pins or connector oxidation:
       1 If damage is found, repair or replace as necessary.
       2 Do a cleaning of the connectors using a BRUSH - BRISTLED with stoddard solvent (Material No.CP2011) AMM 73-21-50-210-001.
     (c) Do the electrical test of the No. 1 bearing vibration sensor (4002EV) AMM 77-31-10-720-002.
       1 If the resistance values are out of the limits, replace the SENSOR-NO. 1 BRG VIB [4002EV] at the next shop maintenance opportunity.
NOTE: The No. 1 bearing vibration sensor cannot be replaced on-wing.
     (d) Do an electrical test of the TRF vibration sensor:
       1 Disconnect the aircraft harness from the vibration sensor. If necessary, use PLIERS - NOSE, SOFT, LONG.
       2 Measure the insulation resistance with a Megohmeter 0-100 Megohms, U= 50 VDC between:
. Pins 1 and 2
. Pins 1 and 3
. Pin 2 and connector body
. Pin 3 and connector body.
       3 The insulation resistance is expected to be greater than 20 Megohms. If any of these measurements are less than 20 Megohms, the sensor is not serviceable.
       4 If the TRF vibration sensor is not serviceable, it must be replaced AMM 77-31-30-000-001 and AMM 77-31-30-400-001.
     (e) If the check (a), (b) and (c) are correct:
  • Do the operational test of the Engine Vibration Monitoring Unit EVMU through the Centralized Fault Display System (CFDS) AMM 77-32-34-710-040.
   (2) Do the following checks if aircraft structure vibration/rumble was also reported by the crew.
NOTE: During descent or approach in icing conditions, ice may build up on the fan blade and spinner cone and consequently lead to increase the fan vibration level on the engine(s). In this case, no maintenance action is required.
     (a) Do a check of the fan blades AMM 72-21-00-210-025 and LPT Stage 4 blades for shingling or damage.
NOTE: A black light inspection of the fan blades can help find soft body impact. Refer to CFMI SPM 70-00-06-800-007.
       1 If the check is not correct:
         a If fan blade damage or mid-span shroud shingling, repair as necessary.
         b If LPT Stage 4 blades shingling, use procedure AMM 72-54-00-290-002.
     (b) Do a check and an inspection of the accessories and QEC components. This includes the check and inspection of:
  • the accessory gearbox mounts
  • the links and brackets of the accessories to make sure they are not loose or broken
  • the cowling brackets, hinges and rigging
  • the pneumatic system for correct condition and rigging.
       1 If the check is not correct, repair or replace as necessary.
     (c) If the checks (a) and (b) are correct:
     (d) If same crew observation is still reported during following flight(s):
Subtask 77-00-00-810-120-B ** ON A/C NOT FOR ALL
A. If the fault symptom is identified on the lower ECAM display unit by the crew observation: ENG 1(2)-FAN VIBRATION higher than or equal to 4 units and less than 6 units:
NOTE: Trouble Shooting is recommended at next maintenance opportunity not interfering with Revenue Service operation.
   (1) Do the following checks if no aircraft structure vibration/rumble was reported by the crew.
NOTE: If momentary vibration on ECAM is greater than 4 units but in order of less than 1 minute, no maintenance action is required provided indication is no associated with aircraft vibration felt by the crew and the indication did not repeat during the flight or following flights.
     (a) Do a check of the wiring, connectors and receptacles between ASM 773202:
  • the No. 1 vibration sensor (4002EV) to the EVMU (2EV)
  • the TRF vibration sensor (4003EV) to the EVMU (2EV).
     (b) Check for damaged pins or connector oxidation:
       1 If damage is found, repair or replace as necessary.
       2 Do a cleaning of the connectors using a BRUSH - BRISTLED with stoddard solvent (Material No.CP2011) AMM 73-21-50-210-002.
     (c) Do the electrical test of the No. 1 bearing vibration sensor (4002EV) AMM 77-31-10-720-001.
       1 If the resistance values are out of the limits, replace the SENSOR-NO. 1 BRG VIB [4002EV] at the next shop maintenance opportunity.
NOTE: The No. 1 bearing vibration sensor cannot be replaced on-wing.
     (d) Do an electrical test of the TRF vibration sensor:
       1 Disconnect the aircraft harness from the vibration sensor. If necessary, use PLIERS - NOSE, SOFT, LONG.
       2 Measure the insulation resistance with a Megohmeter 0-100 Megohms, U= 50 VDC between:
. Pins 1 and 2
. Pins 1 and 3
. Pin 2 and connector body
. Pin 3 and connector body.
       3 The insulation resistance is expected to be greater than 20 Megohms. If any of these measurements are less than 20 Megohms, the sensor is not serviceable.
       4 If the TRF vibration sensor is not serviceable, it must be replaced AMM 77-31-30-000-002 and AMM 77-31-30-400-002.
     (e) If the check (a), (b) and (c) are correct:
  • do the operational test of the Engine Vibration Monitoring Unit EVMU through the Centralized Fault Display System (CFDS) AMM 77-32-34-710-040.
   (2) Do the following checks if aircraft structure vibration/rumble was also reported by the crew.
NOTE: During descent or approach in icing conditions, ice may build up on the fan blade and spinner cone and consequently lead to increase the fan vibration level on the engine(s). In this case, no maintenance action is required.
     (a) Do a check of the fan blades AMM 72-21-00-210-009 and LPT Stage 4 blades for shingling or damage.
NOTE: A black light inspection of the fan blades can help find soft body impact. Refer to CFMI SPM 70-00-06-800-007.
       1 If the check is not correct:
         a If fan blade damage or mid-span shroud shingling, repair as necessary.
         b If LPT Stage 4 blades shingling, use procedure AMM 72-54-00-290-006.
     (b) Do a check and an inspection of the accessories and QEC components. This includes the check and inspection of:
  • the accessory gearbox mounts
  • the links and brackets of the accessories to make sure they are not loose or broken
  • the cowling brackets, hinges and rigging
  • the pneumatic system for correct condition and rigging.
       1 If the check is not correct, repair or replace as necessary.
     (c) If the checks (a) and (b) are correct:
     (d) If same crew observation is still reported during following flight(s):
[Rev.8 from Aug 2018] 2026.04.04 04:37:33 UTC
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