# SDR 9901846729

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 26, 1999
- Submitted: March 26, 2000
- Operation: Air carrier
- Aircraft: N629US
- Make and model: Boeing 747251F
- Aircraft serial: 22388
- System (JASC): [2913 · Hydraulic Pump (Electric/Engine), Main](https://openairdocs.org/jasc/2913)
- Part: Pump
- Condition: Malfunctioned
- Location: Nr 4 Hyd Syst
- Stage of operation: CL
- Nature of condition: J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/9901846729

## Discrepancy

DURING CLIMB, THE NR 4 HYDRAULIC QUANTITY INDICATED ZERO.  AIRCRAFT RETURNED TO MNL AND LANDED WITHOUT INCIDENT.  REPLACED THE HYDRAULIC QUANTITY TRANSMITTER AND ENGINE DRIVEN HYDRAULIC PUMP.  OPERATIONAL CHECK GOOD.

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