# AD 48-21-01: Accelerator Pump Linkage

- Type: Airworthiness directive
- Status: Current
- Products: Wytwornia Sprzetu Komunikacyjnego 6A4-150-B3 and 6A4-150-B31
- Superseded by: Nothing supersedes this AD
- Product type: Engine
- Registered aircraft: 623 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/649C8556291CFC2586256A340056EE54.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/48-21-01

## The airworthiness directive

48-21-01 BELLANCA: Applies to All Aircraft Equipped With Franklin Model 6A4-150- B3 and B31 Engines.

Compliance required after each 25 hours of operation.

To prevent possible binding of accelerator pump linkage in Marvel-Schebler MA-3-SPA carburetor, check for worn accelerator pump linkage. Worn parts should be replaced. Marvel- Schebler have a kit (Part A666-581) available for this purpose.

(Franklin Service Bulletin No. 61 covers this same subject.)

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS E-238](https://openairdocs.org/tcds/E-238): Franklin Sp. z.o.o.; names 2 of 7 models: 6A4-150-B3, 6A4-150-B31

## 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: 623 (0 by airframe model, 623 by engine model)
- Makers: Stinson 479, Bellanca 102, Universal Stinson 36, Cessna 1, Consolidatedvultee Acft 1, Fletcher 1, Groelz 1, Interstate 1, Stits Playboy 1

Models with the most aircraft:

- [Franklin 6A4150 series](https://openairdocs.org/engine/franklin-6a4150-series): 623 aircraft (engine model)

All 1 models: https://openairdocs.org/ad/48-21-01/models.md
Every aircraft: https://openairdocs.org/ad/48-21-01/aircraft.md

Its text cites no advisory circulars or STCs.

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