# SDR 99ZZZX4516

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 12, 1999
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: N111WB
- Make and model: Lear 35LEAR
- Aircraft serial: 003
- System (JASC): [2910 · Hydraulic System, Main](https://openairdocs.org/jasc/2910)
- Part: Shut-Off Valve
- Condition: Misinstalled
- Location: Hydraulic System
- Stage of operation: IN
- Nature of condition: W
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/99ZZZX4516

## Discrepancy

DURING A RECENT 300/600 HOUR INSPECTION, THE HYDRAULIC FIREWALL SHUT-OFF VALVES WERE FOUND WIRED BACKWARDS.  WHEN THE LEFT FIREWALL T-HANDLE WAS PULLED, THE RT HYDRAULIC SHUT-OFF VALVE WOULD CLOSE AND VISA VERSA.

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