Franklin O-150
# Franklin O-150

The Franklin O-150 (company designation 4AC-150) was an American air-cooled aircraft engine of the late 1930s. The engine was of four-cylinder, horizontally-opposed layout and displaced 150 cu in (2 L). The power output was nominally 40 hp (30 kW).

## Applications

* Aeronca 50 Chief
* Bartlett Zephyr
* Clutton-Tabenor FRED
* Fetterman Chickadee
* Payne MC-7 pusher
* Piper J-3 Cub
* Rose Parakeet
* Taylorcraft BF-65
* Taylorcraft L-2

## Engines on display

* Aerospace Museum of California - Franklin 0-150 (4AC-150)

## Specifications (4AC-150)

Data from Jane's all the World's Aircraft 1938.

### General characteristics

* Type: 4-cylinder air-cooled horizontally opposed aircraft piston engine
* Bore: 3.625 in (92.1 mm)
* Stroke: 3.625 in (92.1 mm)
* Displacement: 149.6 cu in (2.45 L)
* Length: 27.5 in (70 cm)
* Width: 34.375 in (87.3 cm)
* Height: 18.375 in (46.7 cm)
* Dry weight: 155 lb (70 kg)

### Components

* Valvetrain: Pushrod and rocker operated overhead valves. One intake, one exhaust
* Fuel system: Stromberg NA-S2 updraught carburetor
* Fuel type: 70 Octane gasoline
* Oil system: Wet sump full pressure system
* Cooling system: Air-cooled

### Performance

* Power output: 40 hp (30 kW) at 1,875 rpm
* Compression ratio: 6.66:1
* Fuel consumption: 4.4 gal/h (17 L/h)
* Specific fuel consumption: 0.54 lb/hp/h
