# SDR ASAA2023082944853

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 29, 2023
- Submitted: August 31, 2023
- Operation: Air carrier
- Aircraft: [N486AS](https://openairdocs.org/aircraft/N486AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 44107
- Aircraft time: 29,519 hours, 9,264 cycles
- System (JASC): [7500 · Engine Bleed Air System](https://openairdocs.org/jasc/7500)
- Part: Regulator
- Part number: 1074847
- Part serial: 7610
- Condition: Faulty
- Location: #1 Engine
- Part time: 63,234 hours, 21,699 cycles
- Stage of operation: TX
- How discovered: V
- Nature of condition: J
- Precautionary procedure: D
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2023082944853

## Discrepancy

AFTER ENGINE RUN START LEFT LEFT DUCT PRESSURE INDICATOR SHOWED 9 PSI AND THEN A SPLIT BETWEEN LEFT AND RIGHT INDICSATORS OF GREATER THAN 20 PSI ABOVE IDLE. GROUNDED - YES. PERFORMED ENGINE AIR BLEED HEALTH CHECK AND FOUND HIGH STAGE REGULATOR AND HGH STAGE VALVE AT FAULT.REMOVED AND REPLACED HIGH STAGE REGULATOR REF MM 36-11-07-000-801 AND 36-11-07-400-801 AND REMOVED AND REPLACED HIGH STAGE VALVE REF MM 36-11-06-000-801 AND 36-11-06-400-801 OPS AND LEAK CHECK GOOD.DUCT PRASSURE HOLDS STEADY FOR BOTH SIDED @ 20 PSI.GROUND VERIFICATION SUCCESSFUL.

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