# SDR HDNA201660823008

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 23, 2016
- Submitted: August 24, 2016
- Operation: Air carrier
- Aircraft: [N535LL](https://openairdocs.org/aircraft/N535LL), registered now
- Make and model: Urocop EC 135 P2
- Registry model: [Urocop EC 135 P2](https://openairdocs.org/model/eurocopter-deutschland-ec-135-p2) (OpenAirDocs)
- Aircraft serial: 0817
- Aircraft time: 4,783 hours
- Engine: Pwa PW206B2
- System (JASC): [7920 · Engine Oil Distribution (Airframe Furnished)](https://openairdocs.org/jasc/7920)
- Part: Thermal Bypass
- Part number: L792M2002102
- Condition: Failed
- Location: Zone 200
- Stage of operation: CR
- How discovered: O
- Nature of condition: M, J
- Precautionary procedure: A, B
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/HDNA201660823008

## Discrepancy

THERMAL BYPASS VALVE FAILED IN CLOSED POSITION NOT ALLOWING OIL TO OIL COOLER.

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