The Lycoming IO-580 engine is a horizontally opposed , six-cylinder aircraft engine featuring three cylinders per side, manufactured by Lycoming Engines .
70-538: There is no carburetted version of the engine, which would have been designated O-580 and therefore the base model is the IO-580. This engine family competes with the Continental IO-550 series which are also six-cylinder engines with similar power output and weight. The IO-580 had originally been developed at the behest of Cessna, who were looking for a modern engine to power their Cessna 206 Stationair. Development
140-420: A cold start . In order to ensure an adequate supply at all times, carburetors include a reservoir of fuel, called a "float chamber" or "float bowl". Fuel is delivered to the float chamber by a fuel pump . A floating inlet valve regulates the fuel entering the float chamber, assuring a constant level. Unlike in a fuel injected engine, the fuel system in a carbureted engine is not pressurized. For engines where
210-437: A manual gearbox , stick shift , standard , and stick . Most automobile manual transmissions have several gear ratios that are chosen by locking selected gear pairs to the output shaft inside the transmission. Manual transmissions feature a driver-operated clutch pedal and a hand-operated gear stick or shift lever, or, on a motorcycle; a hand-operated clutch lever, and a foot-operated gearshift lever. Historically, cars had
280-467: A venturi (aka "barrel"). Fuel is introduced into the air stream through small tubes (the main jets ) at the narrowest part of the venturi, where the air is at its highest speed. Downstream of the venturi is a throttle (usually in the form of a butterfly valve ) which is used to control the amount of air entering the carburetor. In a car, this throttle is connected to the vehicle's throttle pedal, which varies engine speed. At lesser throttle openings,
350-413: A driver's steering effort. However, hydraulic steering is being replaced by electric power steering , because it eliminates the hydraulic pump, and increases fuel efficiency. In modern cars the four-wheel braking system is controlled by a pedal to the left of the accelerator pedal. There is usually also a parking brake which operates the rear brakes only (or less commonly, the front brakes only, as in
420-429: A flexible diaphragm on one side of the fuel chamber, connected to a needle valve which regulates the fuel entering the chamber. As the flowrate of the air in the chamber (controlled by the throttling valve/butterfly valve) decreases, the diaphragm moves inward (downward), which closes the needle valve to admit less fuel. As the flowrate of the air in the chamber increases, the diaphragm moves outward (upward) which opens
490-540: A fully machined combustion chamber. The first IO-580 was type certified on 12 August 1997 on the regulatory basis of FAR 33 effective February 1, 1965 as amended to 33-1 through 33-18. The engine is certified for use in either tractor or pusher configuration installations. Data from Lycoming Specialty Datasheet and Type Certificate Data Sheet No. E00004NY, Revision 1. Related development Comparable engines Related lists Carburetor A carburetor (also spelled carburettor or carburetter )
560-526: A heat stove around the exhaust manifold. It was connected to the air filter intake via tubing and supplied warmed air to the air filter. A vacuum controlled butterfly valve pre heat tube on the intake horn of the air cleaner would open allowing cooler air when engine load increased. Throttle pedal Car controls are the components in automobiles and other powered road vehicles , such as trucks and buses , used for driving and parking. While controls like steering wheels and pedals have existed since
630-440: A low-pressure area in the idle passage/port thus causing fuel to flow through the idle jet. The idle jet is set at some constant value by the carburetor manufacturer, thus flowing a specified amount of fuel. Many carburetors use an off-idle circuit, which includes an additional fuel jet which is briefly used as the throttle starts to open. This jet is located in a low-pressure area behind the throttle. The additional fuel it provides
700-414: A manual overdrive switch. Semi-automatic transmissions are mechanically the same as a conventional manual transmission, but do not have a manually-operated clutch mechanism; instead facilitating the driver, by using automation system to control the clutch. These systems still require the driver's input and involvement for manually changing gear ratios, though, and will not change gear automatically for
770-464: A patent for a "gas or vapor engine", which ran on turpentine mixed with air. The design did not reach production. In 1875 German engineer Siegfried Marcus produced a car powered by the first petrol engine (which also debuted the first magneto ignition system). Karl Benz introduced his single-cylinder four-stroke powered Benz Patent-Motorwagen in 1885. All three of these engines used surface carburetors, which operated by moving air across
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#1732909638428840-424: A range from 300 to 315 hp (224 to 235 kW). The engine has a fuel injection system which meters fuel in proportion to the induction airflow through air-bled nozzles at the individual cylinder intake ports. The engine has a displacement of 583 cubic inches (9.554 litres) and produces a maximum of 315 hp (235 kW) in its B1A version. The cylinders have air-cooled heads cast from aluminum-alloy with
910-406: A single carburetor shared between all of the cylinders, though some high-performance engines historically had multiple carburetors. The carburetor works on Bernoulli's principle : the static pressure of the intake air reduces at higher speeds, drawing more fuel into the airstream. In most cases (except for the accelerator pump ), the driver pressing the throttle pedal does not directly increase
980-475: A spring-loaded cable and are held in place with a ratcheting mechanism until released. In the 2000s, direct-acting electronic parking brakes controlled by a switch (as in the Volkswagen eGolf ) are becoming more common, replacing cable-actuated mechanical systems. In rallying there is often a hydraulic handbrake for the rear wheels, operated by a long, vertical lever extending to near the steering wheel. This
1050-414: A strong green-tinted light, were popular until after World War I; even though the first electric headlights were introduced in 1898 (and those were battery-powered), it wasn't until high-wattage bulbs and more powerful car electrical generating systems were developed in the late 1910s that electric lighting systems entirely superseded acetylene. The first automobiles were steered with a tiller sometimes on
1120-415: A variety of instruments mounted on the dashboard to indicate driving parameters and the state of the mechanics. The placement of the instruments can vary. While they are usually mounted behind the steering wheel, they may also be mounted centrally below the windshield , or integrated into the center stack above the climate control and audio system . The standard gauges found on road vehicles include
1190-748: Is a device used by a gasoline internal combustion engine to control and mix air and fuel entering the engine. The primary method of adding fuel to the intake air is through the Venturi tube in the main metering circuit, though various other components are also used to provide extra fuel or air in specific circumstances. Since the 1990s, carburetors have been largely replaced by fuel injection for cars and trucks, but carburetors are still used by some small engines (e.g. lawnmowers, generators, and concrete mixers) and motorcycles. In addition, they are still widely used on piston engine driven aircraft. Diesel engines have always used fuel injection instead of carburetors, as
1260-432: Is a gear lever that engages a low-ratio gearbox. Other levers may switch between two- and four-wheel drive and differential locks. Some cars have a freewheel that disengages the driveshaft from the driven shaft. This happens when the driven shaft rotates faster than the driveshaft. For example, Saab used a freewheel system in their earlier vehicles, to let the engine disconnect from the transmission while coasting. This
1330-429: Is designed to facilitate handbrake turns rather than for parking, so lacks a ratcheting mechanism. The throttle , which controls fuel and air supply to the engine and is also known as the "accelerator" or "gas pedal", is normally the right-most floor pedal. It has a fail-safe design – a spring, which returns it to the idle position when not depressed by the driver. Normally the throttle and brake are operated by
1400-415: Is held shut by engine vacuum, is often used to do so. As the airflow through the carburetor increases the reduced manifold vacuum pulls the power valve open, allowing more fuel into the main metering circuit. In a two-stroke engine , the carburetor power valve operates in the opposite manner: in most circumstances the valve allows extra fuel into the engine, then at a certain engine RPM it closes to reduce
1470-400: Is limited mainly by the fuel's viscosity so that the fuel flow tends to be proportional to the pressure difference. So jets sized for full power tend to starve the engine at lower speed and part throttle. Most commonly this has been corrected by using multiple jets. In SU and other (e.g. Zenith-Stromberg ) variable jet carburetors, it was corrected by varying the jet size. The orientation of
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#17329096384281540-405: Is often used to prevent icing. This system consists of a secondary air intake which passes around the exhaust, in order to heat the air before it enters the carburetor. Typically, the system is operated by the pilot manually switching the intake air to travel via the heated intake path as required. The carburetor heat system reduces the power output (due to the lower density of heated air) and causes
1610-641: Is spelled "carburetor" in American English and "carburettor" in British English . Colloquial abbreviations include carb in the UK and North America or Carby in Australia. Air from the atmosphere enters the carburetor (usually via an air cleaner ), has fuel added within the carburetor, passes into the inlet manifold , then through the inlet valve(s) , and finally into the combustion chamber . Most engines use
1680-399: Is used to compensate for the reduced vacuum that occurs when the throttle is opened, thus smoothing the transition from the idle circuit to the main metering circuit. In a four-stroke engine it is often desirable to provide extra fuel to the engine at high loads (to increase the power output and reduce engine knocking ). A 'power valve', which is a spring-loaded valve in the carburetor that
1750-507: The direct-shift gearbox . Some automatic transmission vehicles have extra controls that modify the choices made by the transmission system. These controls depend on the engine and road speed. Automatic gear selectors generally have a straight pattern, beginning at the most forward position with park, and running through reverse, neutral, drive, and then to the lower gears. Cars have controls for headlamps , fog lamps, turn signals, and other automotive lighting . Turn signals are activated by
1820-524: The Carter Carburetor WCFB and the identical Rochester 4GC, introduced in various General Motors models for 1952. Oldsmobile referred the new carburetor as the "Quadri-Jet" (original spelling) while Buick called it the "Airpower". In the United States, carburetors were the common method of fuel delivery for most US-made gasoline (petrol) engines until the late 1980s, when fuel injection became
1890-687: The Saab 99 and in the Citroën Xantia ). This has traditionally been operated by a lever between the front seats called a hand brake , but also appeared as a lever between the driver's seat and the door (as in the Porsche 911 ), a knob pulled away from the dash (as in the Volkswagen Transporter ), a foot-operated pedal (as in the Nissan Leaf ), and other less common arrangements. All of these controls pull on
1960-603: The choke valve , ignition timing , and spark arrestor . In the past, all cars had manual controls for starting and running the engine. Now, modern cars not only have automated controls, but they also have controls that are not directly used to drive the vehicle. These controls include air conditioning , navigation systems , on-board computers , in-car entertainment , windscreen wiper , and touchscreen panels. These controls vary in scope and design between different types of cars. They may also be located and operated differently in other road vehicles such as motorcycles , where
2030-405: The computer-controlled , single-clutch, automated manual transmission , pioneered by BMW and Ferrari , began appearing on mass-production automobiles in the mid-1990s; one example is Alfa Romeo 's Selespeed , which is the same system used by Ferrari and BMW. The first mass-production dual-clutch transmission design was introduced with the 4th-generation Volkswagen Golf R32 in 2003, with
2100-414: The 1970s. EEC legislation required all vehicles sold and produced in member countries to have a catalytic converter after December 1992. This legislation had been in the pipeline for some time, with many cars becoming available with catalytic converters or fuel injection from around 1990. A significant concern for aircraft engines is the formation of ice inside the carburetor. The temperature of air within
2170-502: The Saab, is that it makes engine braking unavailable although it could be manually engaged or disengaged by a control in the foot-well. Fixed wheel engagement, using the foot, could be difficult, as it involved pulling a 'T handle' intended for manual operation. Some cars, such as the Rover P4 , include a manual switch to engage or disengage the freewheel. Manual transmission is also known as
Lycoming IO-580 - Misplaced Pages Continue
2240-413: The air speed through the venturi is insufficient to maintain the fuel flow, therefore the fuel is instead supplied by the carburetor's idle and off-idle circuits . At greater throttle openings, the speed of air passing through the venturi increases, which lowers the pressure of the air and draws more fuel into the airstream. At the same time, the reduced manifold vacuum results in less fuel flow through
2310-450: The barrels consist of "primary" barrel(s) used for lower load situations and secondary barrel(s) activating when required to provide additional air/fuel at higher loads. The primary and secondary venturi are often sized differently and incorporate different features to suit the situations in which they are used. Many four-barrel carburetors use two primary and two secondary barrels. A four-barrel design of two primary and two secondary barrels
2380-420: The carburetor can be reduced by up to 40 °C (72 °F), due to a combination of the reduced air pressure in the venturi and the latent heat of the evaporating fuel. The conditions during the descent to landing are particularly conducive to icing, since the engine is run at idle for a prolonged period with the throttle closed. Icing can also occur in cruise conditions at altitude. A carburetor heat system
2450-537: The carburetor is a key design consideration. Older engines used updraft carburetors, where the air enters from below the carburetor and exits through the top. From the late 1930s, downdraft carburetors become more commonly used (especially in the United States), along with side draft carburetors (especially in Europe). The main metering circuit consists of a pipe which reduces to a narrows before widening again, forming
2520-466: The choke based on the temperature of the engine's coolant liquid, an electrical resistance heater to do so, or air drawn through a tube connected to an engine exhaust source. A choke left closed after the engine has warmed up increases the engine's fuel consumption and exhaust gas emissions, and causes the engine to run rough and lack power due to an over-rich fuel mixture. However, excessive fuel can flood an engine and prevent it from starting. To remove
2590-462: The clutch and brake to the right and left. Modern cruise control was invented in 1948. Vehicles that generate power with an internal combustion engine (ICE) are generally equipped with a transmission or gearbox to change the speed-torque ratio and the direction of travel. This does not usually apply to electric vehicles because their motors can drive the vehicle both forward and backward from zero speed. In some four-wheel drive vehicles there
2660-408: The compression-based combustion of diesel requires the greater precision and pressure of fuel-injection. The name "carburetor" is derived from the verb carburet , which means "to combine with carbon", or, in particular, "to enrich a gas by combining it with carbon or hydrocarbons ". Thus a carburetor mixes intake air with hydrocarbon-based fuel, such as petrol or AutoGas (LPG). The name
2730-425: The driver to alert other drivers of their intent to turn or change lanes. While the modern turn signal was patented in 1938, electric turn-signal lights date back to 1907. As of 2013, most countries require turn signals to be included on all vehicles driven on public roadways. The turn signal lever is usually activated by a horizontal lever protruding from the steering column. Vehicles are generally equipped with
2800-509: The driver. The desire for driver convenience led to the widespread implementation of the now-popular hydraulic automatic transmission design in the 1940s, followed by the first mass-production continuously variable transmission (CVT), the Variomatic , in 1958. Automatic transmission with manumatic (manual) gear shifting controls started to appear on mass-production cars in the early-1990s, starting with Porsche 's Tiptronic system. Later,
2870-485: The engine in steady-state conditions, the inertia of fuel (being higher than that of air) causes a temporary shortfall as the throttle is opened. Therefore, an accelerator pump is often used to briefly provide extra fuel as the throttle is opened. When the driver presses the throttle pedal, a small piston or diaphragm pump injects extra fuel directly into the carburetor throat. The accelerator pump can also be used to "prime" an engine with extra fuel prior to attempting
Lycoming IO-580 - Misplaced Pages Continue
2940-418: The excess fuel, many carburetors with automatic chokes allow it to be held open (by manually, depressing the accelerator pedal to the floor and briefly holding it there while cranking the starter) to allow extra air into the engine until the excess fuel is cleared out. Another method used by carburetors to improve the operation of a cold engine is a fast idle cam , which is connected to the choke and prevents
3010-433: The float chamber is located close to the engine, heat from the engine (including for several hours after the engine is shut off) can cause the fuel to heat up to the point of vaporization. This causes air bubbles in the fuel (similar to the air bubbles that necessitate brake bleeding ), which prevents the flow of fuel and is known as 'vapor lock'. To avoid pressurizing the float chamber, vent tubes allow air to enter and exit
3080-407: The float chamber. These tubes usually extend into the carburetor throat, placed to prevent fuel from sloshing out of them into the carburetor. If an engine must be operated when the carburetor is not in an upright orientation (for example in a chainsaw or airplane), a float chamber and gravity activated float valve would not be suitable. Instead, a diaphragm chamber is typically used. This consists of
3150-414: The flow of air at the entrance to the carburetor. This increases the vacuum in the main metering circuit, causing more fuel to be supplied to the engine via the main jets. Prior to the late 1950s the choke was manually operated by the driver, often using a lever or knob on the dashboard . Since then, automatic chokes became more commonplace. These either use a bimetallic thermostat to automatically regulate
3220-417: The following: These gauges are supplemented by an assortment of warning lights that indicate the currently selected transmission gear mode , the generic check engine light , and the current status of various vehicle systems. The layout and design of these instruments have evolved over the years by being implemented as digital readouts rather than the traditional analog dial-type indicators. Depending on
3290-426: The fuel entering the engine. Instead, the airflow through the carburetor increases, which in turn increases the amount of fuel drawn into the intake mixture. The main disadvantage of basing a carburetor's operation on Bernoulli's Principle is that being a fluid dynamic device, the pressure reduction in a venturi tends to be proportional to the square of the intake airspeed. The fuel jets are much smaller and fuel flow
3360-465: The fuel entering the engine. This is done in order to extend the engine's maximum RPM, since many two-stroke engines can temporarily achieve higher RPM with a leaner air-fuel ratio. This is not to be confused with the unrelated exhaust power valve arrangements used on two-stroke engines. A metering rod or step-up rod system is sometimes used as an alternative to a power valve in a four-stroke engine in order to supply extra fuel at high loads. One end of
3430-480: The hand control. The combination of governed engine speed with foot throttle override is in many ways similar to a modern cruise control . In spite of this development, steering column mounted hand throttles remained common, especially in mass-produced cars such as the Ford Model T . Later cars used both a foot pedal and a hand lever to set the minimum throttle. The 1918 Stutz Bearcat had a central throttle pedal with
3500-424: The idle and off-idle circuits. During cold weather fuel vaporizes less readily and tends to condense on the walls of the intake manifold, starving the cylinders of fuel and making cold starts difficult. Additional fuel is required (for a given amount of air) to start and run the engine until it warms up, provided by a choke valve . While the engine is warming up the choke valve is partially closed, restricting
3570-409: The intake air filter to be bypassed, therefore the system is only used when there is a risk of icing. If the engine is operating at idle RPM, another method to prevent icing is to periodically open the throttle, which increases the air temperature within the carburetor. Carburetor icing also occurs on other applications and various methods have been employed to solve this problem. On inline engines
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#17329096384283640-411: The intake air travelling through the carburetor is pressurized (such as where the carburetor is downstream of a supercharger ) the entire carburetor must be contained in an airtight pressurized box to operate. However, this is not necessary where the carburetor is upstream of the supercharger. Problems of fuel boiling and vapor lock can occur in carbureted engines, especially in hotter climates. Since
3710-490: The intake and exhaust manifolds are on the same side of the head. Heat from the exhaust is used to warm the intake manifold and in turn the carburetor. On V configurations, exhaust gases were directed from one head through the intake cross over to the other head. One method for regulating the exhaust flow on the cross over for intake warming was a weighted eccentric butterfly valve called a heat riser that remained closed at idle and opened at higher exhaust flow. Some vehicles used
3780-420: The invention of cars, other controls have developed and adapted to the demands of drivers. For example, manual transmissions became less common as technology relating to automatic transmissions became advanced. Earlier versions of headlights and signal lights were fueled by acetylene or oil. Acetylene was preferred to oil, because its flame is resistant to both wind and rain. Acetylene headlights, which gave
3850-473: The left or right, sometimes in the centre. The steering wheel was first used when Alfred Vacheron competed in the 1894 Paris–Rouen motor race in a Panhard et Levassor . In 1898, steering wheels became a standard feature of Panhard et Levassor cars. They were introduced in the U.S. by Packard in 1899, and by 1908 were on most models. Power steering helps drivers steer by augmenting the driver's steering effort. Power steering has used hydraulics to reduce
3920-480: The needle valve to admit more fuel, allowing the engine to generate more power. A balanced state is reached which creates a steady fuel reservoir level, that remains constant in any orientation. Other components that have been used on carburetors include: The basic design for a carburetor consists of a single venturi (main metering circuit), though designs with two or four venturi (two-barrel and four-barrel carburetors respectively) are also quite commonplace. Typically
3990-475: The preferred method. One of the last motorsport users of carburetors was NASCAR, which switched to electronic fuel injection after the 2011 Sprint Cup series . NASCAR still uses the four-barrel carburetor in the NASCAR Xfinity Series . In Europe, carburetors were largely replaced by fuel injection in the late 1980s, although fuel injection had been increasingly used in luxury cars and sports cars since
4060-488: The right foot, while the clutch is operated by the left foot. However, some drivers sometimes mistake the accelerator for the brake, leading to sudden unintended acceleration and causing 16,000 accidents per year in the US. There are also drivers who intentionally practice left-foot braking . Early cars had a hand lever to control the throttle, either directly, or by controlling an engine speed governor which in turn controlled both
4130-489: The rods is tapered, which sits in the main metering jets and acts as a valve for fuel flow in the jets. At high engine loads, the rods are lifted away from the jets (either mechanically or using manifold vacuum), increasing the volume of fuel can flow through the jet. These systems have been used by the Rochester Quadra jet and in the 1950s Carter carburetors. While the main metering circuit can adequately supply fuel to
4200-435: The small lubrication available from the closed, coasting, throttle. Freewheeling can also be used to help reduce high exhaust gas temperatures in two stroke models caused by prolonged use of the throttle at higher RPM. Freewheeling was retained in the four-stroke variant, until the end of production and in the Saab 99 with the 1709 cc Triumph engine. A minor drawback to the freewheel, particularly for drivers unfamiliar with
4270-490: The starter was operated by the driver pressing a button that was mounted on the floor or dashboard. This type of control has now returned with the use of keyless entry . Early Chevrolet cars had the starter pedal to the right of the accelerator, with a secondary throttle control knob on the dashboard because it was difficult to operate the starter pedal and pump the gas pedal at the same time. Some other historical engine controls, which are automated in modern passenger cars, were
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#17329096384284340-518: The throttle and timing. In 1900 the Wilson-Pilcher car was introduced in Britain which had a hand controlled speed governor, and a foot throttle which could override the action of the governor. Unlike modern throttle pedals this could be raised to accelerate the car or depressed to slow it, "and thus quick accelerations or retardations can be effected" without interfering with the governed speed set using
4410-399: The throttle from closing fully while the choke is in operation. The resulting increase in idle speed provides a more stable idle for a cold engine (by better atomizing the cold fuel) and helps the engine warm up quicker. The system within a carburetor that meters fuel when the engine is running at low RPM. The idle circuit is generally activated by vacuum under the throttle plate, which causes
4480-448: The throttle is controlled by a hand lever and the gear shift is operated by a pedal. Some types of vehicle controls are found in rail vehicles . For example, some trams and light rail vehicles like the PCC streetcar use automobile-style pedals to control the speed. In Formula One auto racing, many vehicle parameters can be set by the driver during a race. Controls for these are mounted on
4550-544: The top of a vessel containing the fuel. The first float-fed carburetor design, which used an atomizer nozzle , was introduced by German engineers Wilhelm Maybach and Gottlieb Daimler in their 1885 Grandfather Clock engine . The Butler Petrol Cycle car—built in England in 1888—also used a float-fed carburetor. The first carburetor for a stationary engine was patented in 1893 by Hungarian engineers János Csonka and Donát Bánki . The first four-barrel carburetors were
4620-412: The type of vehicle, more specialized instruments may be used such as a trip computer , fuel economy gauge, or battery level display. Before the appearance of the starter motor, engines were started by various difficult and dangerous methods. These methods included: wind-up springs, gunpowder cylinders , and human-powered techniques such as a removable hand-crank . In 1896, the first electric starter
4690-469: Was a feature added because of the limited lubrication in the two-stroke engine. A petroil-lubricated two-stroke requires lubrication according to its speed, but provides this lubrication according to the amount of its throttle opening. Where the engine operates at high RPM and low throttle (such as when coasting down a long hill), the lubrication provided may be inadequate. With the freewheel, a coasting engine could reduce its speed to idling, thus requiring only
4760-527: Was commonly used in V8 engines to conserve fuel at low engine speeds while still affording an adequate supply at high. The use of multiple carburetors (e.g., a carburetor for each cylinder or pair of cylinders) also results in the intake air being drawn through multiple venturi. Some high-performance engines have used multiple two-barrel or four-barrel carburetors, for example six two-barrel carburetors on Ferrari V12s. In 1826, American engineer Samuel Morey received
4830-598: Was installed on an Arnold , one of the first motor cars manufactured in the United Kingdom. Charles Kettering and Henry Leland later invented and filed U.S. patent 1,150,523 for the first electric starter in America in 1911. In 1912, the Cadillac Model Thirty became the first American car to have a starter installed. Before Chrysler 's 1949 innovation of the key-operated combination ignition-starter switch,
4900-450: Was slow, and the aircraft was delayed to wait for the engine. When production began, Cessna found problems with the cylinders, and instead of further delaying the introduction, they moved the 206 to the older and less powerful 260 hp Lycoming IO-540 . Lycoming eventually addressed all of the problems, and the engine found some use in various aerobatic aircraft, but no serious production was undertaken. The IO-580 family of engines covers
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