# AD 52-20-02: Master Rod Bearing Oil Supply

- Type: Airworthiness directive
- Status: Current
- Products: Curtiss-Wright/Marquette Double Row Cyclone 739C18BA3, Double Row Cyclone 745C18BA3, Double Row Cyclone 745C18BA4, Double Row Cyclone 749C18BD1 and Double Row Cyclone 749C18BD3
- Superseded by: Nothing supersedes this AD
- Product type: Engine
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/75A362924A3710808625685F00578922.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/52-20-02

## The airworthiness directive

52-20-02 WRIGHT: Applies to All Models C18BA and C18BD Engines.

Compliance required as soon as possible but not later than October 31, 1952.

To prevent crankpin sludge from washing into the master rod bearing oil supply passages causing failure of the bearing, the use of oil dilution must be discontinued and the dilution lines disconnected or removed. This restriction on oil dilution is to continue until an adequate sludge controlling device is developed and incorporated in these engines.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS E-218](https://openairdocs.org/tcds/E-218): Curtiss-Wright/Marquette Inc.; names 5 of 5 models: Double Row Cyclone 749C18BD3, Double Row Cyclone 745C18BA4, Double Row Cyclone 749C18BD1, Double Row Cyclone 745C18BA3, Double Row Cyclone 739C18BA3

## Registered aircraft it may apply to (OpenAirDocs)

No registered aircraft matched the models it names.

Its text cites no advisory circulars or STCs.

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