51-28-02: Oil Pump Gears
FAA order 51-28-02 is an airworthiness directive. The FAA's subject line: Oil Pump Gears. System: engine.
What it applies to as the FAA lists it
- Kind of product
- Engine
- Makes
- Wytwornia Sprzetu Komunikacyjnego
- Models
- 6V4-178-B3, 6V4-178-B31, 6V4-178-B32, 6V4-178-B33, 6V4-200-C32, 6V4-200-C33
Dates and paperwork
- Docket
- Unknown
- Status
- Current
- The FAA's document
- Read the order on the FAA's site
The order itself the regulatory text, as published
Show the full text (881 characters)
51-28-02 FRANKLIN: Applies to Model 6V4-178 Series Engines Prior to Serial Number 17690 and 6V4- 200 Series Engines Prior to Serial Number 26235.
Compliance required as indicated.
To preclude the possibility of oil pump failure, oil pump gears (P/N 10673 and 17736) must be inspected at each 300 hours of operation. Excessively galled gears must be replaced. If same part numbers are used for replacements, the 300-hour inspections will still apply. If carbonitrided oil pump drive gear, P/N 19377, and oil pump driven gear, P/N 19373, are installed, no further inspection is required. When these new carbonitrided gears are installed, suffix "P" must be stamped after the serial number of the engine on the nameplate - example: No. 1700P.
(Franklin Service Bulletin No. 86, revised November 1, 1951, covers this same subject.)
This supersedes AD's 51-22-02 and 51-11-03.
Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of November 6, 2026. Connections as data: /graph/directive/51-28-02.json · aircraft systems.