# SDR ASAA2020091173161

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 7, 2020
- Submitted: September 11, 2020
- Operation: Air carrier
- Aircraft: [N428AS](https://openairdocs.org/aircraft/N428AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 36353
- Aircraft time: 17,524 hours, 5,543 cycles
- Engine: Cfmint CFM567B27E
- System (JASC): [7220 · Turbine Engine Air Inlet Section](https://openairdocs.org/jasc/7220)
- Part: Shim
- Part number: 3402523070
- Condition: Worn
- Location: Nr 1 Engine
- Stage of operation: NR
- How discovered: O
- Nature of condition: E
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2020091173161

## Discrepancy

NR 1 ENGINE TREND DATA STILL SHOWS A RISE IN LOW PRESSURE ROTOR VIBRATION LEVELS WITH EXCESSIVE FAN SCATTER.  GROUNDED - YES.  ACCOMPLISHED TSR STEPS 1-5.  REPLACED 24 SHIMS DUE TO WORN MOLYKOTE COATING & WEAR DOWN TO PARENT METAL.  REPLACED ALL AXIAL STOP PINS ON REAR SPINNER CONE.  REF T/C 78472010 FAN BLADE LUBRICATION.  NO OTHER DEFECTS NOTED.  THIS CLEARS TSR, SEAMC CHRIS NOTIFIED.

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