# AD 77-07-07: Oil Level Gage

- Type: Airworthiness directive
- Status: Current
- Products: Lycoming Engines O-320-H2AD
- Effective: February 20, 1979
- Superseded by: Nothing supersedes this AD
- Product type: Engine
- Amendment: 39-3415
- Registered aircraft: 27,398 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/BF436A5A0FCBD0DB86256E120055B30B.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/77-07-07

## The airworthiness directive

77-07-07 AVCO LYCOMING: Amendment 39-2864 as amended by Amendment 39-3415. Applies to the O-320-H2AD series Lycoming engines Serial Numbers L-101-76 thru L-1049-76. Compliance required within 50 hours in service after the effective date of this AD, unless previously accomplished. To prevent the incorrect installation of the P/N LW-14784 or the P/N LW-15481 oil level gage modify the P/N 75675 oil filler extension by installing a P/N LW-15498 perforated sleeve as follows: (a) Remove the P/N 75675 oil filler extension from the engine. (b) Insert the P/N LW-15498 perforated sleeve in the oil filler extension. Make certain that the flanged end rest evenly against the recessed surface below the threads inside of the oil filler extension. Locate and mark the perforated sleeve where it protrudes through the base of the oil filler extension. (c) After locating this position, remove the perforated sleeve from the oil filler extension and insert a length of 3/4 inch diameter steel rod into the sleeve. Place the steel rod and sleeve in a vise or other suitable holding device and with a narrow chisel cut the perforated sleeve as shown in figure 1 at the location marked per instructions of item (b) of this AD. (d) Remove the 3/4 inch diameter steel rod and install the perforated sleeve in the oil filler extension. Bend the chiseled section of the perforated sleeve at the seam to form a tab as shown in figure 2.

  (e) Install the reworked oil filler extension and perforated sleeve in the engine, making certain that the P/N 70457 gasket is properly in place between the oil filler extension and the engine crankcase. Install either P/N LW-14784 or P/N LW-15481 oil level gage. Apply lockwire as required. (f) Upon submission of substantiating data through an FAA Maintenance Inspector, the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region, may adjust the compliance time. (Note: AVCO Lycoming Service Bulletin No. 407A covers this subject). Amendment 39-2864 became effective April 11, 1977. This amendment 39-3415 is effective February 20, 1979

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS E-274](https://openairdocs.org/tcds/E-274): Lycoming Engines; names 1 of 60 models: O-320-H2AD

## 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: 27,398 (0 by airframe model, 27,398 by engine model)
- Makers: Piper 11,632, Cessna 9,982, Grumman American Avn. 605, Bellanca 588, Beech 398, Champion 295, Robinson Helicopter 289, American Champion 250, American 116, Gulfstream American 95

Models with the most aircraft:

- [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series): 27,057 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)
- [Aerotec O-320 series](https://openairdocs.org/engine/aerotec-o-320-series): 2 aircraft (engine model)

All 4 models: https://openairdocs.org/ad/77-07-07/models.md
Every aircraft: https://openairdocs.org/ad/77-07-07/aircraft.md

Its text cites no advisory circulars or STCs.

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