AD 80-14-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Lycoming Engines | LO-360-E1A6D | AVCO LYCOMING Model O-320-H, O-360-E, LO-360-E Series Engines |
| engine | Lycoming Engines | O-320-H1AD | AVCO LYCOMING Model O-320-H, O-360-E, LO-360-E Series Engines |
| engine | Lycoming Engines | O-320-H1BD | AVCO LYCOMING Model O-320-H, O-360-E, LO-360-E Series Engines |
| engine | Lycoming Engines | O-320-H2AD | AVCO LYCOMING Model O-320-H, O-360-E, LO-360-E Series Engines |
| engine | Lycoming Engines | O-320-H2BD | AVCO LYCOMING Model O-320-H, O-360-E, LO-360-E Series Engines |
| engine | Lycoming Engines | O-320-H3AD | AVCO LYCOMING Model O-320-H, O-360-E, LO-360-E Series Engines |
| engine | Lycoming Engines | O-320-H3BD | AVCO LYCOMING Model O-320-H, O-360-E, LO-360-E Series Engines |
| engine | Lycoming Engines | O-360-E1A6D | AVCO LYCOMING Model O-320-H, O-360-E, LO-360-E Series Engines |
Unsafe Condition
Failure of valves due to installation of improperly hardened upper exhaust valve spring seats.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Within 25 hours in service after the effective date, inspect all upper exhaust valve spring seats for part number LW-16475 with 'KLI' letters in a curved pattern as per Service Bulletin No. 447. Replace seats without 'KLI' markings with compliant ones per AVCO Lycoming S/B No. 435 or Overhaul Manual P/N 60294-9.
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Compliance Time
Within the next 25 hours in service after the effective date of this AD
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Affected Aircraft
AVCO Lycoming Model O-320-H series engines S/N L-101-76 thru L-7608-76; O-360-E series S/N L-101-77 thru L-455-77; LO-360-E series S/N L-101-72 thru L-451-72; all remanufactured engines of these models shipped before November 16, 1979.
AI-generated summary from the source AD text. Verify against the official source before acting.
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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