# SDR KCSA2025111865

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 18, 2025
- Submitted: November 20, 2025
- Operation: Air carrier
- Aircraft: [N708CK](https://openairdocs.org/aircraft/N708CK), registered now
- Make and model: Boeing 747-4B5
- Registry model: [Boeing 747-4B5](https://openairdocs.org/model/boeing-747-4b5) (OpenAirDocs)
- Aircraft serial: 25275
- Aircraft time: 116,333 hours, 19,874 cycles
- Engine: Pwa PW4056
- Engine time: 79,046 hours, 10,874 cycles
- System (JASC): [2913 · Hydraulic Pump (Electric/Engine), Main](https://openairdocs.org/jasc/2913)
- Part: Pump
- Part number: 3508807
- Part serial: MX238197
- Condition: Faulted
- Location: Hyd System
- Stage of operation: CR
- How discovered: O
- Nature of condition: J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/KCSA2025111865

## Discrepancy

100280839: HYD QTY LOW 1 DEMAND PUMP AND ENGINE PUMP BOTH OFF BEFORE SYS FLUID 0. ACTION TAKEN: REMOVED AND REPLACED #1 EDP HYD 1. IAW B747-400 AMM 29-11-05-004 AND 29-11-05-904. ALL CHECKS GOOD. NO LEAKS NOTED.  DRY MOTOR PERFORMED. NO DEFECTS NOTED.

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