# AD 77-01-03: Carburetor Air Filter Boxes

- Type: Airworthiness directive
- Status: Current
- Products: Piper PA-28-151
- Effective: January 14, 1977
- Published: January 10, 1977
- Issued: December 29, 1976
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-2801
- Registered aircraft: 961 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0C2DAF3A2563639A8625699E004A962C.0001
- DRS record last changed: November 21, 2025
- Page: https://openairdocs.org/ad/77-01-03

## The airworthiness directive

77-01-03 PIPER AIRCRAFT CORPORATION: Amendment 39-2801. Applies to Model PA-28-151 airplanes, serial numbers 28-7415001 through 28-7715278 and 28-7715289 certificated in all categories.

Compliance required within the next 10 hours' time in service after the effective date of this AD, unless already accomplished.

To detect and correct those carburetor air filter boxes that do not contain a drain hole, accomplish the following:

  (a) Open the top right side engine cowl door to gain access to the carburetor air filter box, Piper Part Number 35462-00, at the right hand bottom section of the engine compartment.

  (b) Check visually and by feel to determine whether the carburetor air filter box contains a drain hole in the lower rear corner of the outside half of the carburetor air filter box. (See figure) This check may be performed by the pilot.

AD 77-01-03

  (c) If the box contains a drain hole, accomplish (f).

  (d) If the box does not contain a drain hole, accomplish (e) and (f).

  (e) Modify the carburetor air filter box as follows:

  (1) Remove and disassemble the carburetor air filter box.

  (2) Drill a .19 inch diameter hole in the lower rear corner of the outside half of the carburetor air filter box. (See figure)

  (3) Reassemble and reinstall the carburetor air filter box.

  (f) Close the engine cowl and return the airplane to service.

Piper Service Bulletin 536 also pertains to this subject.

This amendment becomes effective January 14, 1977.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 2A13](https://openairdocs.org/tcds/2A13): Piper Aircraft Inc.; names 1 of 18 models: PA-28-151

## 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: 961 (961 by airframe model, 0 by engine model)
- Makers: Piper 961

Models with the most aircraft:

- [Piper PA-28-151](https://openairdocs.org/model/piper-pa-28-151): 961 aircraft (airframe model)

All 2 models: https://openairdocs.org/ad/77-01-03/models.md
Every aircraft: https://openairdocs.org/ad/77-01-03/aircraft.md

Its text cites no advisory circulars or STCs.

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