(e) If nothing is found:
- Dispatch the aircraft. Vibration level must be monitored closely.
NOTE : HP unbalance is the first cause of core vibration, may be
____ not perceptible through trouble shooting actions. The presence of high N2 vibration requires to schedule the
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engine removal for root cause identification at shop level.
(3) If the fault symptom is identified on the lower ECAM display unit by the crew observation ENG1/2 - CORE VIB higher than or equal to 4.2 units and less than 5.4 units for more than one minute: - open the cowlings (Ref. AMM TASK 71-11-00-210-001) and do a visual
inspection around the engine (centerbody plug, piping and brackets fan cowl and core cowl area).
(a) Do a check and an inspection of the accessories and QEC components. This includes the check and inspection of:
- the accessory gear box mounts,
- the link and brackets of the accessories to make sure they are 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 required.
(b) If nothing is found:
1 Do a check of the wiring, connectors and receptacles (Ref. ASM
_
77-32/02) between:
- the No. 1 bearing vibration sensor (4002EV) and the EVMU (2EV),
- the TRF vibration sensor (4003EV) and the EVMU (2EV).
2 Disconnect the harnesses from the No. 1 bearing and the TRF
_
sensors,
- do a check for damaged pins or connector oxidation (Ref. AMM TASK 71-50-00-210-001).
a If damage is found:
_
- repair or replace as required.
b If no damage is found:
_
- do a cleaning of the connectors using a bristle brush with stoddard solvent (Material No. CP2011) (Ref. AMM TASK 73-21-50-210-002).
3 Do an electrical test of the No. 1 bearing vibration sensor
_ and the TRF vibration sensor:
- disconnect the aircraft harness from the vibration sensor connectors. If necessary, use soft nose pliers.
- measure the insulation resistance with a megohmeter 0-100 megohms, V=45VDC between: . pins 1 and 2 . pins 1 and 3 . pin 2 and connector body . pin 3 and connector body,
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a If one of these measurements is less than 20 megohms:
_ - the sensor is not serviceable.
b If one of the two vibration sensors is found not
_
serviceable:
- configure the MCDU to read the other vibration sensor output (Ref. AMM TASK 77-32-34-860-041).
NOTE : If the TRF vibration sensor is not serviceable, it
____ should be replaced (Ref. AMM TASK 77-31-30-000-002) and (Ref. AMM TASK 77-31-30-400-002).
NOTE : The No. 1 bearing vibration sensor cannot be
____ replaced on-wing.
(c) If nothing is found:
- do the operational test of the Engine Vibration Monitoring Unit (EVMU) through the Centralized Fault Display System (CFDS) (Ref. AMM TASK 77-32-34-710-040).
(d) Do a check of the electric master magnetic chip detector visual indicator (Ref. AMM TASK 79-35-00-040-042) and the magnetic chip detector (Ref. AMM TASK 79-00-00-281-002) and the scavenge screen plugs (Ref. AMM TASK 79-00-00-281-003).
1 If you find magnetic particles:
_
- follow the related instructions per (Ref. AMM TASK 79-00-00-281-002) and NDT Manual (section CHIP ANALYSIS).
2 If no magnetic particles are found:
_
- do a borescope inspection of the high pressure compressor rotor assembly (Ref. AMM TASK 72-31-00-290-002) and of the high pressure turbine blades (Ref. AMM TASK 72-52-00-290-001).
(e) If nothing is found:
- configure the MCDU to read the other vibration sensor output (Ref. AMM TASK 77-32-34-860-041).
(f) If nothing is found:
- dispatch the aircraft. Vibration level must be monitored closely and reported to CFMI on a regular basis.
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本文鏈接地址：A320 Trouble Shooting Manual 排故手冊 發動機指示(91)
