The first internal combustion engine light enough in weight was the gasoline engine, invented by a German named Otto.
At the same time Dr. Rudolph Diesel was working on the diesel engine. The Diesel engine is similar to the gasoline engine in many ways. There are many variations in engine arrangements, but the basic parts of most 4-stroke cycle engines are similar.
In the in-line arrangement the cylinders are lined up in a single row. The V-type engine is called so as the cylinders form 2 rows or "banks", set at an angle to each other to form the letter V.
The diesel engine gets its power from the expansion of burning gases. The diesel engine depends on the heat of compression for ignition of the fuel.
Liquid fuel that contains more heat energy than gasoline is diesel
oil.
Diesel oil is slower burning, but it produces more power. Diesel engines also must be heavier than gasoline engines, but they are more efficient when working under heavy loads at low speeds.
The advantages of the diesel over the gasoline engine are as follows:
a).more economic operation;
b).higher compression ratio;
c).reduced maintenance costs;
d).good pulling power.
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Engines
The two most common types of engines for cars are the petrol engine and diesel engine.
Petrol engines are usually lighter and smaller than diesel engines. This makes them cheaper, and this is why most cars use petrol engines. Petrol engines are also less noisy than diesel engines. They usually go foster. On the other hand, diesel engines use less fuel than petrol engines, and this is why trucks use them. They are also safer than petrol engines, because there is less danger of fire.
There are two main types of petrol engine - 4-stroke and 2-stroke. All cars use 4-stroke engines. But most motorbikes use 2-stroke engines. They are lighter and smaller than 4-stroke engines, and are therefore cheaper.
Section 4
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The "UAS" Model
This model designed as "go anywhere" vehicle is built by the Ulyanovsk Plant. It gives high performance under all conditions. All the four wheels of this model are driving ones. Roadless is easily overcome at medium speeds. Stable suspension gives great riding comfort even under off-road conditions.
To protect passengers and the driver from sun rays, winds and rains the UAS is equipped with a weather proof hood. In cold weather an effective heater system may be switched on.
This model possesses excellent road stability and is easy in control. Well-balanced, synchromesh gearbox, effective brakes provide additional conveniences for the driver. Maintenance of the car is extremely simple, as all points, which are frequently lubricated and adjusted are easily accessible. The body is an all-metal, two-door, eight - seater construction. The clutch is of a single dry plate type.
The transmission has three forward and one reverse speeds. The lower gear can be put in only when the front axle is engaged.
1. At what plant is the model built?
2. Does it give high performance under all conditions?
3. At what speeds is roadless overcome?
4. What is done to protect passengers from wind and rain?
5. What may be switched on in cold weather?
6. Why is maintenance of the car extremely simple?
7. How many speeds has the transmission?
Section 5
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