# SDR CALA2026083119034

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 31, 2026
- Submitted: August 31, 2026
- Operation: Air carrier
- Aircraft: [N73406](https://openairdocs.org/aircraft/N73406), registered now
- Make and model: Boeing 737924
- Aircraft serial: 30123
- Aircraft time: 68,641 hours, 28,884 cycles
- System (JASC): [4950 · APU Bleed Air System](https://openairdocs.org/jasc/4950)
- Part: O-Ring
- Condition: Damaged
- Location: Apu Duct
- Stage of operation: NR
- How discovered: O
- Nature of condition: B
- Precautionary procedure: J
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026083119034

## Discrepancy

APU AUTO SHUTDOWN CABIN ODOR ASSOCIATED NOTED IN CABIN APU BITE SHOWED ADD OIL. SVCD APU OIL. PERFORMED GVI AND FOUND APU BLEED DUCT MISSING HARDWARE.  REPORTED APU BLEED AIR DUCT MISSING HARDWARE, WILL NEED TO BE REPLACED MISSING O-RING SEAL AT APU BLEED DISCHARGE FLANGE. INSTALLED NEW BOLTS AT FLANGE. ONE INSERT WAS FOUND STRIPPED. REMOVED BOLT AND INSERT AND REPLACED WITH -16 BOLT AND NUTS IAW AMM 49-52-15-300-801-C1, PERFORMED APU OP TEST IAW AMM 49-11-00-710-801.  RAN APU VERFIED NO ODOR IN CABIN. OPS & LEAK CHKD GOOD. APU BLEED PSI WITHIN LIMITS.

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