# SDR 2004UALA00175

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 28, 2004
- Submitted: March 11, 2004
- Operation: Air carrier
- Aircraft: [N799UA](https://openairdocs.org/aircraft/N799UA), registered now
- Make and model: Boeing 777222
- Aircraft serial: 26926
- Aircraft time: 25,902 hours, 4,032 cycles
- Engine: Pwa PW4090
- System (JASC): [7200 · Engine (Turbine/Turboprop)](https://openairdocs.org/jasc/7200)
- Part: Engine
- Condition: Overheated
- Location: Right
- Stage of operation: DE
- How discovered: O
- Nature of condition: M, J
- Precautionary procedure: E
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2004UALA00175

## Discrepancy

RIGHT ENGINE OIL TEMP TO 145C AND OIL PRESSURE DROPPED TO 40-45 PSI TOP OF DESCENT INTO KIX.  SHUT DOWN ENGINE. NR 1 BEARING FAILURE.  THIS IS THE MAIN THRUST BALL BEARING SUPPORTING THE N1 ROTOR.  OUTER RACE HEAVILY SPALLED THROUGH 100¡ ARC. ONE BALL HEAVILY SPALLED; ALL OTHERS, LIGHT-MODERATE SPALLING. CAGE FRACTURED AXIALLY THROUGH ONE BALL POCKET. NO SPALLING ON INNER RACES. BEARING IS PRE PRATT & WHITNEY SERVICE BULLETIN PW4G-112-72-212 PART NUMBER. BEARING WILL BE REPLACED WITH POST SB-212 PN WHICH HAS  INCREASED DURABILITY. NOTE:  ENGINE THRUST BALANCE SYSTEM WAS CONFIRMED TO BE FUNCTIONING NORMALLY.

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