# SDR COZA20171017116

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 13, 2017
- Submitted: October 18, 2017
- Operation: Air carrier
- Aircraft: N732KA
- Make and model: Boeing 737-59D
- Registry model: [Boeing 737-59D](https://openairdocs.org/model/boeing-737-59d) (OpenAirDocs)
- Aircraft serial: 25065
- Aircraft time: 45,486 hours, 39,132 cycles
- System (JASC): [4950 · APU Bleed Air System](https://openairdocs.org/jasc/4950)
- Part: Control Valve
- Part number: 36052392
- Part serial: 20074608
- Condition: Intermittent
- Location: Apu Bay
- Stage of operation: IN
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/COZA20171017116

## Discrepancy

APU DRAGS DOWN DURING MAIN ENGINE START.  REPLACED APU PROPORTIONAL CONTROL VALVE.  ENGINE START AND APU OPERATIONAL CHECKS NORMAL.

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