The priming bulb sucks fuel up into the carburetor which may be empty from the last time the engine was run.
Before you start your engine, you need to prime it. Priming the Carburetor on a Two Stroke Engine Gas and Two-Stroke Oil Needed For a 50:1 Ratio If you do a lot of trimming, obviously it's more economical to buy a larger bottle of oil. In the US, 2.6 fluid ounce bottles of oil are available for making up a gallon of mix. You can normally buy 100 mL plastic bottles of two-stroke oil which is sufficient to make up 5 litres of mix. Swirl the mixture in the container for a few seconds to mix it thoroughly. Try to avoid fuels which contain ethanol as this absorbs moisture over time, oxidizing metal surfaces. 1:40 or 1: 30 is probably a good compromise (i.e. Some manufacturers recommend a 1:25 ratio for their engines, so check your manual. This equates to 20 ml per liter (litre) or 2.6 fluid ounces (US) per gallon (US). In general, the oil-to-gas ratio for a two-stroke engine should be 1:50. Lubrication of two-stroke engines is effected by mixing two-stroke oil with gas before use. Two-stroke oil is designed to burn as cleanly as possible with the fuel. It contains additives which can contaminate the cylinder over time and also it can tar up the piston. They have several advantages over four-stroke engines (like the one in your car or lawn mower).ĭon't use four-stroke motor oil in your engine. Two-stroke (also known as two-cycle or 2t) engines are used on most hand-held garden power tools. Finally, it is transferred to the cylinder where it is burnt to produce power. The mixture flows out of the carburetor and into the crankcase through the intake manifold. (Paint spray guns used off a compressor work on the same principle). This jet works exactly like the spray nozzle on a garden hose and a mist or spray of gas is created, which mixes with the airflow. The drop in pressure causes fuel to be drawn through a jet into the air flowing through the venturi. As air flows through the venturi, it increases in speed, and pressure drops below atmospheric. 
This tube, about 1/2 to 3/4 inch in diameter on a small engine, has a narrowed section called the venturi.
Air is drawn by suction from the engine through a tube in the carburetor. 
As air moves faster, static pressure decreases causing fuel to be sucked into the carburetor and mix with the airflow coming from the air filter. The function of the carburetor is to mix a mist of gasoline and air together to form an explosive mixture which is burned in the cylinder of the engine.Ī carburetor works on Bernoulli's Principle. Engines in older cars and other gas-powered vehicles also had a carburetor before the introduction of fuel injection in the 1980s. © Eugene Brennan What's a Carburetor and How Does It Work?Īll two-stroke engines on trimmers (and also four-stroke engines on lawn mowers, generators, and other small equipment) are fitted with a device called a carburetor (often shortened to carb in North America or carby in Australia).
0 kommentar(er)
