# SDR UIEA2023042200379

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 18, 2023
- Submitted: April 24, 2023
- Operation: Air carrier
- Aircraft: [N408MC](https://openairdocs.org/aircraft/N408MC), registered now
- Make and model: Boeing 747-47UF
- Registry model: [Boeing 747-47UF](https://openairdocs.org/model/boeing-747-47uf) (OpenAirDocs)
- Aircraft serial: 29261
- Aircraft time: 94,195 hours, 15,862 cycles
- System (JASC): [2800 · Aircraft Fuel System](https://openairdocs.org/jasc/2800)
- Part: Transfer Valve
- Part number: 125333
- Part serial: P62521
- Condition: Unknown
- Stage of operation: CR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UIEA2023042200379

## Discrepancy

FUEL TANK #4 LEAKS INTO CENTER TANK AT A RATE OF 100 KILOS PER 11 MINUTES, APPROX 600 PER HOUR UNCONTROLLABLY.(<P>REPLACED BAD #3 MAIN TANK TRANSFER VALVE IAW 747 AMM 28-16-05. LEAK CHECKS C/W NO LEAKS FOUND AT THIS TIME.</P>)

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