Franklin O-175

Summary

The Franklin O-175 (company designation 4AC-176) was an American air-cooled aircraft engine of the 1940s. The engine was of horizontally-opposed four-cylinder and displaced 175 cu in (2.9 L). The power output was nominally 80 hp (60 kW). A later variant was designated O-180, despite sharing the same displacement.

O-175/4AC-176
Type Piston aircraft engine
National origin United States
Manufacturer Franklin Engine Company
First run 1940

A related four-cylinder engine of slightly smaller capacity was known as the O-170 or 4AC-171. It produced 60 hp (45 kW).

VariantsEdit

O-170Edit

4AC-171
60 hp (45 kW)

O-175Edit

4AC-176
4AC-176-B - 65 hp (48 kW) at 2,200 rpm
4AC-176-BA/(O-175-1) - 65 hp (48 kW) at 2,300 rpm
4AC-176-C - 75 hp (56 kW) at 2,500 rpm
4AC-176-D - 80 hp (60 kW) at 2,650 rpm
4AC-176-F - 80 hp (60 kW) at 2,500 rpm
4ACG-176

O-180Edit

4AC-176-F3 (O-180-1)

ApplicationsEdit

Specifications (4AC-176-BA2, O-175-1)Edit

Data from Wilkinson[1]

General characteristics

  • Type: 4-cylinder air-cooled horizontally opposed aircraft piston engine
  • Bore: 4 in (102 mm)
  • Stroke: 3.5 in (89 mm)
  • Displacement: 176 cu in (2.88 l)
  • Length: 28.6 in (726 mm)
  • Width: 30.2 in (767 mm)
  • Height: 20 in (508 mm)
  • Dry weight: 182 lb (82.6 kg)

Components

  • Valvetrain: OHV, 1x inlet valve, 1x exhaust valve operated by pushrods
  • Fuel system: 1x Marvel-Schebler MA-3P updraught carburetor
  • Fuel type: 73 octane gasoline
  • Oil system: Pressure system at 40 psi (3 bar), wet sump
  • Cooling system: Air-cooled

Performance

See alsoEdit

Related lists

ReferencesEdit

Notes
  1. ^ Wilkinson, Paul H. (1945). Aircraft Engines of the world 1945. New York: Paul H. Wilkinson. pp. 88–89.
Bibliography
  • Gunston, Bill. (1986) World Encyclopedia of Aero Engines. Patrick Stephens: Wellingborough. p. 57