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Flooded Engine
A flooded engine is an internal combustion engine that has been fed an excessively rich air-fuel mixture that cannot be ignited. This is caused by the mixture exceeding the upper explosive limit for the particular fuel. An engine in this condition will not start until the excessively rich mixture has been cleared. It is also possible for an engine to stall from a running state due to this condition. Engine flooding was a common problem with carbureted cars, but newer fuel-injected ones are immune to the problem when operating within normal tolerances. Flooding usually occurs during starting, especially under cold conditions or because the accelerator has been pumped. It can also occur during hot starting; high temperatures may cause fuel in the carburetor float chamber to evaporate into the inlet manifold, causing the air/fuel mixture to exceed the upper explosive limit. High temperature fuel may also result in a vapor lock, which is unrelated to flooding but has a similar sympt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Combustion Engine
An internal combustion engine (ICE or IC engine) is a heat engine in which the combustion of a fuel occurs with an oxidizer (usually air) in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal combustion engine, the expansion of the high- temperature and high- pressure gases produced by combustion applies direct force to some component of the engine. The force is typically applied to pistons (piston engine), turbine blades ( gas turbine), a rotor (Wankel engine), or a nozzle (jet engine). This force moves the component over a distance, transforming chemical energy into kinetic energy which is used to propel, move or power whatever the engine is attached to. This replaced the external combustion engine for applications where the weight or size of an engine was more important. The first commercially successful internal combustion engine was created by Étienne Lenoir around 1860, and the first modern internal combustion engine, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Upper Explosive Limit
Mixtures of dispersed combustible materials (such as gaseous or vaporised fuels, and some dusts) and oxygen in the air will burn only if the fuel concentration lies within well-defined lower and upper bounds determined experimentally, referred to as flammability limits or explosive limits. Combustion can range in violence from deflagration through detonation. Limits vary with temperature and pressure, but are normally expressed in terms of volume percentage at 25 °C and atmospheric pressure. These limits are relevant both in producing and optimising explosion or combustion, as in an engine, or to preventing it, as in uncontrolled explosions of build-ups of combustible gas or dust. Attaining the best combustible or explosive mixture of a fuel and air (the stoichiometric proportion) is important in internal combustion engines such as gasoline or diesel engines. The standard reference work is still that elaborated by Michael George Zabetakis, a fire safety engineering speciali ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carburetor
A carburetor (also spelled carburettor) is a device used by an 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, however 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, however carburetors are still used by some small engines (e.g. lawnmowers, generators and concrete mixers) and motorcycles. Diesel engines have always used fuel injection instead of carburetors. Etymology 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 is spelled "carburetor" in American Eng ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fuel-injected
Fuel injection is the introduction of fuel in an internal combustion engine, most commonly automotive engines, by the means of an injector. This article focuses on fuel injection in reciprocating piston and Wankel rotary engines. All compression-ignition engines (e.g. diesel engines), and many spark-ignition engines (i.e. petrol engines, such as Otto or Wankel), use fuel injection of one kind or another. Mass-produced diesel engines for passenger cars (such as the Mercedes-Benz OM 138) became available in the late 1930s and early 1940s, being the first fuel-injected engines for passenger car use. In passenger car petrol engines, fuel injection was introduced in the early 1950s and gradually gained prevalence until it had largely replaced carburettors by the early 1990s. The primary difference between carburetion and fuel injection is that fuel injection atomizes the fuel through a small nozzle under high pressure, while a carburettor relies on suction created by intake air ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accelerator (car)
A throttle is the mechanism by which fluid flow is managed by constriction or obstruction. An engine's power can be increased or decreased by the restriction of inlet gases (by the use of a throttle), but usually decreased. The term ''throttle'' has come to refer, informally, to any mechanism by which the power or speed of an engine is regulated, such as a car's accelerator pedal. What is often termed a ''throttle'' (in an aviation context) is also called a thrust lever, particularly for jet engine powered aircraft. For a steam locomotive, the valve which controls the steam is known as the regulator. Internal combustion engines In an internal combustion engine, the throttle is a means of controlling an engine's power by regulating the amount of fuel or air entering the engine. In a motor vehicle the control used by the driver to regulate power is sometimes called the throttle, accelerator, or gas pedal. For a gasoline engine, the throttle most commonly regulates the amount ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vapor Lock
Vapor lock is a problem caused by liquid fuel changing state to gas while still in the fuel delivery system of gasoline-fueled internal combustion engines. This disrupts the operation of the fuel pump, causing loss of feed pressure to the carburetor or fuel injection system, resulting in transient loss of power or complete stalling. Restarting the engine from this state may be difficult. The fuel can vaporize due to being heated by the engine, by the local climate or due to a lower boiling point at high altitude. In regions where fuels with lower viscosity (and lower boiling threshold) are used during the winter to improve engine startup, continued use of the specialized fuels during the summer can cause vapor lock to occur more readily. Causes and incidence Vapor lock was far more common in older gasoline-fuel systems incorporating a low-pressure mechanical fuel pump driven by the engine, located in the engine compartment and feeding a carburetor. Such pumps were typically l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Starter Motor
A starter (also self-starter, cranking motor, or starter motor) is a device used to rotate (crank) an internal-combustion engine so as to initiate the engine's operation under its own power. Starters can be electric, pneumatic, or hydraulic. The starter can also be another internal-combustion engine in the case, for instance, of very large engines, or diesel engines in agricultural or excavation applications. Internal combustion engines are feedback systems, which, once started, rely on the inertia from each cycle to initiate the next cycle. In a four-stroke engine, the third stroke releases energy from the fuel, powering the fourth (exhaust) stroke and also the first two (intake, compression) strokes of the next cycle, as well as powering the engine's external load. To start the first cycle at the beginning of any particular session, the first two strokes must be powered in some other way than from the engine itself. The starter motor is used for this purpose and it is not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolock
Hydrolock (a shorthand notation for hydrostatic lock or hydraulic lock) is an abnormal condition of any device which is designed to compress a gas by mechanically restraining it; most commonly the reciprocating internal combustion engine, the case this article refers to unless otherwise noted. Hydrolock occurs when a volume of liquid greater than the volume of the cylinder at its minimum (end of the piston's stroke) enters the cylinder. Since liquids are nearly incompressible the piston cannot complete its travel; either the engine must stop rotating or a mechanical failure must occur. Symptoms and damage If an engine hydrolocks while at speed, a mechanical failure is likely. Common damage modes include bent or broken connecting rods, a fractured crank, a fractured head, a fractured block, crankcase damage, damaged bearings, or any combination of these. Forces absorbed by other interconnected components may cause additional damage. Physical damage to metal parts can manife ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autoignition Temperature
The autoignition temperature or kindling point of a substance is the lowest temperature in which it spontaneously ignites in a normal atmosphere without an external source of ignition, such as a flame or spark. This temperature is required to supply the activation energy needed for combustion. The temperature at which a chemical ignites decreases as the pressure is increased. *The ignition temperature of a substance is the lowest temperature at which the substance starts combustion. *Substances which spontaneously ignite in a normal atmosphere at naturally ambient temperatures are termed pyrophoric. Autoignition temperatures of liquid chemicals are typically measured using a flask placed in a temperature-controlled oven in accordance with the procedure described in ASTM E659. When measured for plastics, autoignition temperature can be also measured under elevated pressure and at 100% oxygen concentration. The resulting value is used as a predictor of viability for high-oxyg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 mixture by an electric spark, while containing combustion pressure within the engine. A spark plug has a metal threaded shell, electrically isolated from a central electrode by a ceramic insulator. The central electrode, which may contain a resistor, is connected by a heavily insulated wire to the output terminal of an ignition coil or magneto. The spark plug's metal shell is screwed into the engine's cylinder head and thus electrically grounded. The central electrode protrudes through the porcelain insulator into the combustion chamber, forming one or more spark gaps between the inner end of the central electrode and usually one or more protuberances or structures attached to the inner end of the threaded shell and designated the ''s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Choke Valve
In internal combustion engines with carburetors, a choke valve or choke modifies the air pressure in the intake manifold, thereby altering the air–fuel ratio entering the engine. Choke valves are generally used in naturally aspirated engines to supply a richer fuel mixture when starting the engine. Most choke valves in engines are butterfly valves mounted upstream of the carburetor jet to produce a higher partial vacuum, which increases the fuel draw. In heavy industrial or fluid engineering contexts, including oil and gas production, a choke valve or choke is a particular design of valve with a solid cylinder placed inside another slotted or perforated cylinder. Carburetor A choke valve is sometimes installed in the carburetor of internal combustion engines. Its purpose is to restrict the flow of air, thereby enriching the fuel-air mixture while starting the engine. Depending on engine design and application, the valve can be activated manually by the operator of the eng ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vapor Lock
Vapor lock is a problem caused by liquid fuel changing state to gas while still in the fuel delivery system of gasoline-fueled internal combustion engines. This disrupts the operation of the fuel pump, causing loss of feed pressure to the carburetor or fuel injection system, resulting in transient loss of power or complete stalling. Restarting the engine from this state may be difficult. The fuel can vaporize due to being heated by the engine, by the local climate or due to a lower boiling point at high altitude. In regions where fuels with lower viscosity (and lower boiling threshold) are used during the winter to improve engine startup, continued use of the specialized fuels during the summer can cause vapor lock to occur more readily. Causes and incidence Vapor lock was far more common in older gasoline-fuel systems incorporating a low-pressure mechanical fuel pump driven by the engine, located in the engine compartment and feeding a carburetor. Such pumps were typically l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
