# SDR QR9R20220112003

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 12, 2022
- Submitted: January 12, 2022
- Operation: General aviation
- Filed by: [M1 Support Services, repair station QR9R369D](https://openairdocs.org/faa-repair-station/QR9R369D/m1-support-services.md) (OpenAirDocs)
- Make and model: Bolkms BK117C2
- Aircraft serial: 11722159487
- Aircraft time: 2,645 hours
- System (JASC): [7714 · Engine RPM Indicating System](https://openairdocs.org/jasc/7714)
- Part: Sensor
- Part number: 9580115900
- Part serial: 5659
- Condition: Out Of Tolerance
- Stage of operation: HO
- How discovered: V
- Nature of condition: J
- Precautionary procedure: C
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/QR9R20220112003

## Discrepancy

OVERSPEED FAIL 3 TIMES IN 15 MINUTES DURING RUN-UP. DURING TROUBLESHOOTING, WHEN MEASURING THE #1 OVERSPEED SENSOR BETWEEN PINS 2 AND 3 IT READ 42 OHMS, WHICH IS OUT OF TOLERANCE. INSTALLED NEW #1 SIDE ENGINE OVERSPEED SENSOR IAW ENGINE MANUAL 77-14-00-900-802-A01. MOC SUCCESSFULLY COMPLETED.

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