The Continental O-170 engine is the collective military designation for a family of small aircraft engines, known under the company designation of A50, A65, A75 and A80. The line was designed and built by Continental Motors commencing in the 1940s. It was employed as the powerplant for civil and military light aircraft.Christy (1983) The horizontally opposed, four-cylinder engines in this family are all identical in appearance, bore, stroke, dry weight, and piston displacement. All feature a bottom-mounted

updraft carburetor An updraft carburetor is a type of carburetor (a component of engines that mixes air and fuel together) in which the air enters at the bottom and exits at the top to go to the engine. An updraft carburetor was the first type of carburetor in commo ...

fuel delivery system. The higher power variants differ only in compression ratio and maximum allowable rpm, plus minor modifications. The lower power versions are fully convertible to the higher rated versions.

Design and development

In all models of this family of engines the cylinder heads are of

aluminum Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It has ...

alloy, screwed and shrunk onto

steel Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant ty ...

barrels.

Spark plug A spark plug (sometimes, in British English, a sparking plug, and, colloquially, a plug) is a device for delivering electric current from an ignition system to the combustion chamber of a spark-ignition engine to ignite the compressed fuel/air ...

inserts and intake valve seats are made from aluminum-

bronze Bronze is an alloy consisting primarily of copper, commonly with about 12–12.5% tin and often with the addition of other metals (including aluminium, manganese, nickel, or zinc) and sometimes non-metals, such as phosphorus, or metalloids such ...

alloy, while the exhaust valve seats are steel. The engines all employ hydraulic tappets which operate in aluminum guides that are machined into the

crankcase In a piston engine, the crankcase is the housing that surrounds the crankshaft. In most modern engines, the crankcase is integrated into the engine block. Two-stroke engines typically use a crankcase-compression design, resulting in the fuel/a ...

. The tappets are built from four parts, a cam follower body, cup, cylinder, and piston and operate with clearances of to . The

pushrod A valvetrain or valve train is a mechanical system that controls the operation of the intake and exhaust valves in an internal combustion engine. The intake valves control the flow of air/fuel mixture (or air alone for direct-injected engines) ...

s are steel and feature pressed-in ball ends. Lubricating oil is delivered under pressure from the oil sump to the drive bearings and the crankpins through the crankshaft. The cylinder walls and pistons are spray lubricated. Normal operating oil pressure is 35 psi, with minimum idle oil pressure 10 psi.

Variants

Air Zoo December 2019 130 (Continental A-50)

;A50 :, Compression ratio 5.4:1, max rpm 1,900, fuel consumption at cruise 3.8 US gph ;A50-1: ;A50-2: ;A50-3: ;A50-4: ;A50-5: ;A50-6: ;A50-7: ;A65 :, Compression ratio 6.3:1, max rpm 2,300, fuel consumption at cruise 4.4 US gph. The exhaust valves have

stellite Stellite is a range of cobalt-chromium alloys designed for wear resistance. The alloys may also contain tungsten or molybdenum and a small, but important, amount of carbon. History Stellite is a trademarked name of Kennametal Inc. Prior to tha ...

faces. The pistons have three

rings Ring may refer to: * Ring (jewellery), a round band, usually made of metal, worn as ornamental jewelry * To make a sound with a bell, and the sound made by a bell :(hence) to initiate a telephone connection Arts, entertainment and media Film and ...

, although some early production A65s had four piston rings.Teledyne Continental Motors: ''Continental Aircraft Engine Operator's Manual'', pages 4-5. Teledyne Continental Motors, FAA Approved December 1980. Continental Form No. X30012 ;A65-1: ;A65-2: ;A65-3: ;A65-4: ;A65-5: ;A65-6: ;A65-7: ;A65-8: ;A65-8F: :A65-9: ;A65-12: ;A75 :, Compression ratio 6.3:1, max rpm 2,600, fuel consumption at cruise 4.8 US gph. The exhaust valves have stellite faces and the connecting rods have a hole drilled in the rod cap to improve lubrication. The pistons have three rings and smaller piston pins. ;A75-1: ;A75-2: ;A75-3: ;A75-4: ;A75-5: ;A75-6: ;A75-14: ;A80 :, Compression ratio 7.55:1, max rpm 2,700, fuel consumption at cruise 5.2 US gph. The connecting rods have a hole drilled in the rod cap to improve lubrication. The pistons have five rings and smaller piston pins. ;A80-1: ;A80-2: ;A80-3: ;A80-4: ;A80-5: ;A80-6: ;A80-8: ;O-170 :Military designation for the A50, A65, A75, A80 family of engines. ;O-170-1: ;O-170-3: ;O-170-5: ;O-170-7:

Applications

;A50 * Aeronca KCA *

Aeronca 50C The Aeronca Model 50 Chief was an American light plane of the late 1930s. Consumer demand for more comfort, longer range and better instrumentation resulted in its development in 1938, powered by a 50-horsepower (37-kilowatt) Continental, Frankl ...

Aeronca 50TC The Aeronca Model 50 Chief was an American light plane of the late 1930s. Consumer demand for more comfort, longer range and better instrumentation resulted in its development in 1938 in aviation, 1938, powered by a 50-horsepower (37-kilowatt) C ...

* Aeronca S50C *

Luscombe 8 The Luscombe 8 is a series of high-wing, side-by-side-seating monoplanes with conventional landing gear, designed in 1937 and built by Luscombe Aircraft. Development Luscombe Aircraft closed in 1949, with its assets purchased by Temco Air ...

Piper J-3 The Piper J-3 Cub is an American light aircraft that was built between 1938 and 1947 by Piper Aircraft. The aircraft has a simple, lightweight design which gives it good low-speed handling properties and short-field performance. The Cub is Pi ...

Piper J-4 The Piper J-4 Cub Coupe is a two place side-by-side version of the Piper J-3 that was built between 1938 and 1942 by Piper Aircraft. It was Piper's first model with side-by-side seating; combined with docile low-speed handling, this made it a good ...

* Porterfield CP50 * Porterfield CP55 *

Taylorcraft BC The Taylorcraft B is an American light, single-engine, high-wing general aviation monoplane, with two seats in side-by-side configuration, that was built by the Taylorcraft Aviation Corporation of Alliance, Ohio.The Pittsburgh PressMove Stat ...

Taylorcraft BCS The Taylorcraft B is an American light, single-engine, high-wing general aviation monoplane, with two seats in side-by-side configuration, that was built by the Taylorcraft Aviation Corporation of Alliance, Ohio.The Pittsburgh PressMove Stat ...

;A65

Aeronca L-3 The Aeronca L-3 group of observation and liaison aircraft were used by the United States Army Air Corps in World War II. The L-3 series were adapted from Aeronca's pre-war Tandem Trainer and Chief models. Design and development In 1941, the ...

Aeronca S65C The Aeronca Model 50 Chief was an American light plane of the late 1930s. Consumer demand for more comfort, longer range and better instrumentation resulted in its development in 1938, powered by a 50-horsepower (37-kilowatt) Continental, Frankl ...

Aeronca S65CA The Aeronca Model 50 Chief was an American light plane of the late 1930s. Consumer demand for more comfort, longer range and better instrumentation resulted in its development in 1938, powered by a 50-horsepower (37-kilowatt) Continental, Frankl ...

Aeronca 65F The Aeronca Model 50 Chief was an American light plane of the late 1930s. Consumer demand for more comfort, longer range and better instrumentation resulted in its development in 1938, powered by a 50-horsepower (37-kilowatt) Continental, Frankl ...

* Aeronca 65CA *

Aeronca Champion The Aeronca Model 7 Champion, commonly known as the "Champ", or "Airknocker",Bellanca Aircraft Corp, " d: "The Champ only $4,995"" ''Flying Annual & Pilots' Guide,'' 1971 ed., pp.36–37 iff-Davis NY is a single-engine light airplane with a ...

Airdrome Fokker D-VIII The Airdrome Fokker D-VIII is an American amateur-built aircraft, designed and produced by Airdrome Aeroplanes, of Holden, Missouri. The aircraft is supplied as a kit for amateur construction.Vandermeullen, Richard: ''2011 Kit Aircraft Buyer's ...

Bearhawk LSA The Bearhawk LSA is an American Homebuilt aircraft, amateur-built light-sport aircraft, designed by Bob Barrows and produced by Bearhawk Aircraft of Austin, Texas. The aircraft is supplied in the form of plans or a kit for amateur construction. ...

* Cassutt Special * Christavia Mk I * Circa Reproductions Nieuport * Coupé-Aviation JC-01 *

Davis DA-2 __NOTOC__ The Davis DA-2 is a light aircraft designed in the United States in the 1960s and was marketed for Homebuilt aircraft, homebuilding. While it is a low-wing monoplane of largely conventional design with fixed tricycle undercarriage, th ...

* Davis DA-5 * Ercoupe 415C * E & P Special *

Falconar F11 Sporty The Falconar F11 Sporty is a Canadian amateur-built aircraft, that was designed by Chris Falconar and produced by Falconar Avia. Falconar supplied it as a kit or as plans for amateur construction. Today both the F11A and E models are available ...

Fisher Celebrity The Fisher Celebrity is a Canadian two-seat, conventional landing gear, single engined, biplane kit aircraft designed for construction by amateur builders. Fisher Flying Products was originally based in Edgeley, North Dakota, United States but ...

Fisher Dakota Hawk The Fisher Dakota Hawk is a Canadian side-by-side two-seat, conventional landing gear, single-engined, high-wing monoplane kit aircraft designed for construction by amateur builders.Purdy, Don: ''AeroCrafter - Homebuilt Aircraft Sourcebook'', ...

Helmy Aerogypt __NOTOC__ The Helmy Aerogypt was a British four-seat cabin monoplane designed and built by Egyptian Saleh Helmy at Heston Aerodrome in 1938. The Aerogypt I was a low-wing cantilever monoplane initially powered by three 22 hp (16 kW) Do ...

Jackson (1974) * Henderson Little Bear * Interstate SIA Cadet * Jameson RJJ-1 Gipsy Hawk * Jodel D.112 *

Luscombe 8A The Luscombe 8 is a series of high-wing, side-by-side-seating monoplanes with conventional landing gear, designed in 1937 and built by Luscombe Aircraft. Development Luscombe Aircraft closed in 1949, with its assets purchased by Temco Aircr ...

Luscombe 10 __NOTOC__ The Luscombe 10 was a single-seat sport aircraft built in the United States in 1945.Taylor 1989, 613 It was a conventional, low-wing cantilever monoplane with fixed, tailwheel landing gear, designed for aerobatics.Simpson 1995, 239 The ...

* Piper J-4A * Porterfield CP65 * Rearwin Skyranger 165 * Smith MiniplanePlane & Pilot: ''1978 Aircraft Directory'', page 153. Werner & Werner, 1978. *

Stolp SA-900 V-Star The Stolp SA-900 V-Star is an American aerobatic homebuilt biplane, currently produced by Aircraft Spruce & Specialty Co in the form of plans for amateur construction. In the 1990s it was also available as a kit from Stolp Starduster Corpora ...

Taylorcraft BCS12 The Taylorcraft B is an American light, single-engine, high-wing general aviation monoplane, with two seats in side-by-side configuration, that was built by the Taylorcraft Aircraft, Taylorcraft Aviation Corporation of Alliance, Ohio.The Pitt ...

* Taylorcraft 65 * Tayorcraft BC * Taylorcraft BC1265 *

Taylorcraft BCT The Taylorcraft B is an American light, single-engine, high-wing general aviation monoplane, with two seats in side-by-side configuration, that was built by the Taylorcraft Aviation Corporation of Alliance, Ohio.The Pittsburgh PressMove Stat ...

Taylorcraft L-2 The Taylorcraft L-2 Grasshopper is an American observation and liaison aircraft built by Taylorcraft Aircraft, Taylorcraft for the United States Army Air Forces in World War II. Design and development In 1941 the United States Army Air Forces ...

* Taylorcraft Tandem * Turner T-40 *

Warner Revolution I The Warner Revolution I, also marketed as the Spacewalker I, is an American homebuilt aircraft that was designed and produced by Warner Aerocraft of Seminole, Florida. When it was available the aircraft was supplied as a kit or in the form of ...

Wolf W-11 Boredom Fighter The Wolf W-11 Boredom Fighter is an American single-seat biplane designed by Donald Wolf of Huntington, New York. The aircraft is supplied as plans for amateur construction.Bayerl, Robby; Martin Berkemeier; et al: ''World Directory of Leisu ...

;A75 *

* Culver LCA * Jodel D.121 *

Luscombe 8C The Luscombe 8 is a series of high-wing, side-by-side-seating monoplanes with conventional landing gear, designed in 1937 and built by Luscombe Aircraft. Development Luscombe Aircraft closed in 1949, with its assets purchased by Temco Aircr ...

Luscombe 8D The Luscombe 8 is a series of high-wing, side-by-side-seating monoplanes with conventional landing gear, designed in 1937 and built by Luscombe Aircraft. Development Luscombe Aircraft closed in 1949, with its assets purchased by Temco Aircr ...

Piper J-4E The Piper J-4 Cub Coupe is a two place side-by-side version of the Piper J-3 that was built between 1938 and 1942 by Piper Aircraft. It was Piper's first model with side-by-side seating; combined with docile low-speed handling, this made it a good ...

Piper J-5 The Piper J-5 Cub Cruiser was a larger, more powerful version of the basic Piper J-3 Cub. It was designed just two years after the J-3 Cub, and differed by having a wider fuselage with the pilot sitting in the front seat and two passengers sittin ...

* Piper J-5A * Porterfield 75C * Rearwin Skyranger 175 * Stinson Model 105 (HW-75) ;A80 * Harris Geodetic LW 108 * Piper J-5A-80 *

Shirlen Big Cootie The Shirlen Big Cootie is an American homebuilt biplane that was designed by Roy Shirlen. Design and development The Big Cootie is a modernized version of the Powell PH Racer biplane for homebuilt construction. The aircraft is a single seat bip ...

* Stinson Model 105 (HW-80) * Stinson Model 10 *

Vought V-173 The Vought V-173 "Flying Pancake" was an American experimental test aircraft built as part of the Vought XF5U program during World War II. Both the V-173 and the XF5U featured an unorthodox "all-wing" design consisting of flat, somewhat disk-sha ...

Specifications (O-170-3 or A-65-8)

Notes

References