# SDR ASAA2023022142042

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 21, 2023
- Submitted: February 23, 2023
- Operation: Air carrier
- Aircraft: [N409AS](https://openairdocs.org/aircraft/N409AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 41733
- Aircraft time: 36,276 hours, 11,576 cycles
- System (JASC): [3610 · Pneumatic Distribution System](https://openairdocs.org/jasc/3610)
- Part: Regulator
- Part number: 1074847
- Part serial: 5398
- Condition: Faulty
- Location: #1 Engine
- Part time: 74,259 hours, 26,279 cycles
- Stage of operation: IN
- How discovered: V
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2023022142042

## Discrepancy

WHILE PERFORMING INSTALLATION TEST OF MW0311 HARNESS, "BLEED AIR REGULATOR OPERATIONAL TEST", FOUND #1 ENGINE BLEED PSI WOULD NOT GO ABOVE 10 PSI. GROUNDED - YES. PERFORMED #1 ENGINE BLEED AIR SYSTEM HEALTH CHECK PER TASK CARD #NG-36WC-00001, FOUND HIGH STAGE REGULATOR AND HIGH STAGE VALVE FAILED, REMOVED AND REPLACED HSR AND HSV PER B737-900 AMM 36-11-07 AND 36-11-06, OPS CHECK GOOD, HEALTH CHECK SUCCESSFUL, LEAK CHECK GOOD, PER AMM 73-21-06-400-802-F00, PERFORMED PARAGRAPH 5.F (1)(C)2 TO END OF TASK CARD, OPS CHECK NORMAL, ALL PARAMETERS NORMAL.

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