# SDR AALA201910169015

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 15, 2019
- Submitted: June 23, 2020
- Operation: Air carrier
- Aircraft: [N934AN](https://openairdocs.org/aircraft/N934AN), registered now
- Make and model: Boeing 737823
- Aircraft serial: 29531
- Aircraft time: 58,012 hours, 24,041 cycles
- Engine: Cfmint CFM567B20
- Engine time: 56,223 hours, 22,772 cycles
- System (JASC): [7200 · Engine (Turbine/Turboprop)](https://openairdocs.org/jasc/7200)
- Part: Engine
- Condition: Coked
- Location: Left
- Stage of operation: CL
- How discovered: V
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AALA201910169015

## Discrepancy

AIRCRAFT WAS GROUNDED: FLIGHT RETURNED TO ONT ON ACCOUNT OF LEFT ENGINE OIL BYPASS LIGHT ILLUMINATED. AN EMERGENCY WAS DECLARED. MAINTENANCE FOUND COKE/CARBON PARTICLES ON THE SCAVENGE FILTER. REMOVED AND REPLACED L/H ENGINE SCAVENGE OIL FILTER IAW AMM 79-21-06, LEAK CHECK GOOD. REMOVED AND REPLACED L/H ENGINE SCAVENGE OIL FILTER TRANSMITTER IAW AMM 79-21-07, LEAK CHECK GOOD. ACCOMPLISHED MCD AND SCAVENGE SCREENS INSPECTION IAW AMM 79-00-00, LEAK CHECK GOOD.   MAINTENANCE REMOVED AND REPLACED LEFT ENGINE IAW JOB CARD 71-94-01. ALL CHECKS GOOD.

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