# SDR CALA2026010212606

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 29, 2025
- Submitted: January 2, 2026
- Operation: Air carrier
- Aircraft: [N75435](https://openairdocs.org/aircraft/N75435), registered now
- Make and model: Boeing 737924ER
- Aircraft serial: 33529
- Aircraft time: 51,490 hours, 18,507 cycles
- Engine: Cfmint CFM567B262
- System (JASC): [7320 · Fuel Controlling System](https://openairdocs.org/jasc/7320)
- Part: Switch
- Part number: QA07995
- Part serial: YY1102582
- Condition: Faulted
- Location: Nr 2 Engine
- Part time: 37,169 hours, 13,625 cycles
- Stage of operation: DE
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026010212606

## Discrepancy

ENG 2 FUEL FILTER BYPASS LIGHT ON ENG SLOW TO RESPOND AT IDLE POWER SETTING, ENG 2 FUEL FILTER BYPASS CAME ON DURING APPROACH AT AROUND 14,000. FT. IDLE POWER SETTNGS WERE SLOW TO RESPOND. N1/N2 IDLE FLUCTUATING AROUND 30-35. FLUCTUATION ON N1 ONLY, ON ENG 2 R & R ENG 2 FUEL FILTER, NO CONTAMINATION FOUND. FUEL FILTER BYPASS LIGHT STILL CAME ON DURING ENG RUN. SUSPECT FUEL FILTER DIFFERENTIAL PRESSURE SWITCH OR FUEL FILTER CLOGGING INDICATOR.  REQ MEL 7304B FOR FUEL FILTER DIFFERENTIAL PRESSURE INDICATOR ON NR 2 ENG. COMPLIED WITH MEL. ENGINE 2 FUEL FILTER DIFFERENTIAL PRESSURE WARNING SYSTEM INOP. TECHS COMPLIED WITH MEL 7304B METHOD 2 FOR COMPLIANCE.  R & R FUEL FILTER DIFFERENTIAL PRESSURE SWITCH, IAW AMM 73-34-01. OPS CK GOOD & LEAK CK GOOD, FILTER BYPASS LIGHT EXTINGUISHED, BYPASS IN THE CDU, REF FIM 73-05 TASK 801.

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