# AD 80-14-07: Upper Exhaust Valve Spring Seats

- Type: Airworthiness directive
- Status: Current
- Products: Lycoming Engines LO-360-E1A6D, O-320-H1AD, O-320-H1BD, O-320-H2AD, O-320-H2BD, O-320-H3AD, O-320-H3BD and O-360-E1A6D
- Effective: July 7, 1980
- Superseded by: Nothing supersedes this AD
- Product type: Engine
- Amendment: 39-3826
- Registered aircraft: 40,403 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/105E00E2807C50E786256841005AFB39.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/80-14-07

## The airworthiness directive

80-14-07 AVCO LYCOMING: Amendment 39-3826. Applies to O-320-H series engines, S/Ns L-101-76 thru L-7608-76, O-360-E series engines, S/Ns L-101-77 thru L-455-77; LO-360-E series engines, S/Ns L-101-72 thru L-451-72 and all remanufactured engines of these models shipped prior to November 16, 1979. Compliance required as indicated, unless already accomplished. To prevent failure of valves due to installation of improperly hardened upper exhaust valve spring seats, accomplish the following: Within the next 25 hours in service after the effective date of this AD remove the valve rocker box covers and visually inspect all upper exhaust valve spring seats for part number identification. (a) If all four upper exhaust valve spring seats are identified as Part Number LW-16475 followed by the letters "KLI", in a curved pattern as shown in Lycoming Service Bulletin No. 447, the engine may be returned to service. (b) If any of the upper exhaust valve spring seats are identified asPart Number LW-16475 without the letters "KLI", they must be removed and replaced with seats marked as described in paragraph (a) above. Installation of these valve spring seats shall be accomplished per instructions in AVCO Lycoming S/B No. 435 or Lycoming Overhaul Manual P/N 60294-9 or an approved alternate. Compliance with paragraph (a) of AD 80-04-03 or AVCO Lycoming S/B 447 dated January 11, 1980, will constitute compliance with the requirements of this AD. Equivalent methods of compliance may be approved by the Chief, Engineering and Manufacturing Branch, Federal Aviation Administration (FAA) Eastern Region. Upon submission of substantiating data by an owner or operator through an FAA Maintenance Inspector, the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region may adjust the compliance time specified in this AD. This amendment is effective July 7, 1980.

## Affected data sheets (2) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS E-274](https://openairdocs.org/tcds/E-274): Lycoming Engines; names 6 of 60 models: O-320-H3BD, O-320-H2BD, O-320-H2AD, O-320-H3AD, O-320-H1BD, O-320-H1AD
- [TCDS E-286](https://openairdocs.org/tcds/E-286): Lycoming Engines; names 2 of 72 models: O-360-E1A6D, LO-360-E1A6D

## Registered aircraft it may apply to (OpenAirDocs)

Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment.

- Aircraft: 40,403 (0 by airframe model, 40,403 by engine model)
- Makers: Piper 17,628, Cessna 11,409, Mooney 1,556, Grumman American Avn. 1,162, Beech 1,147, Bellanca 760, Robinson Helicopter 497, American Champion 321, Champion 297, Gulfstream American 271

Models with the most aircraft:

- [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series): 27,057 aircraft (engine model)
- [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series): 11,931 aircraft (engine model)
- [Lycoming O-360 series](https://openairdocs.org/engine/lycoming-o-360-series): 1,023 aircraft (engine model)
- [Lycoming O-320 series](https://openairdocs.org/engine/lycoming-o-320-series): 256 aircraft (engine model)
- [Lycoming O-320-H2AD](https://openairdocs.org/engine/lycoming-o-320-h2ad): 83 aircraft (engine model)
- [Lycoming 0-360 series](https://openairdocs.org/engine/lycoming-0-360-series): 44 aircraft (engine model)
- [Lycoming O-360-E1A6D](https://openairdocs.org/engine/lycoming-o-360-e1a6d): 7 aircraft (engine model)
- [Aerotec O-320 series](https://openairdocs.org/engine/aerotec-o-320-series): 2 aircraft (engine model)

All 8 models: https://openairdocs.org/ad/80-14-07/models.md
Every aircraft: https://openairdocs.org/ad/80-14-07/aircraft.md

Its text cites no advisory circulars or STCs.

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