3. Прочитайте текст и выполните следующие за ним упражнения: THE ENGINE 1. The engine is the source of power that makes the car move. It is usually called an internal combustion engine because gasoline is burned within its cylinders or combustion chambers. Most automobile engine have six or eight cylinders. 2. The operating cycle of the four-stroke engine that takes place in the engine cylinder can be divided into four strokes. The upper limit of the piston movement is called the top dead centre. The lower limit of piston movement is called the bottom dead centre. stroke is the piston movement from the top dead centre to the bottom dead centre or from the bottom dead centre to the top dead centre. In other words the piston complete a stroke each time it changes the direction of its motion. 3. Where the entire cycle of events in the cylinder reguires four strokes the engine is called a four-stroke cycle engine. The four strokes are: intake, compression, power and exhaust. 4. Two-cycle engines have also been made, and in such engines the entire cycle of events is completed in two strokes or one revolution of the crankshaft. 5. On the intake stroke the intake valve is opened. The mixture of air and vaporized gasoline is delivered into the cylinder through the inlet valve. On the compression stroke the inlet valve is closed so that the mixture can be compressed. On the power stroke both valves are closed in order to rise pressure during the mixture combustion. On the exhaust stroke the exhaust valve is opened to exhaust the residual gas.

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