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6.Make a list of words characterizing the starting motor.

7.Find out a word or a word expression in the text or remember a similar meaning to the following:

8. Find the answers to the questions given below:

1)What is the liquid fuel mixed with?

2)Where is the liquid fuel vaporized?

3)Where is the fuel-air mixture ignited?

4)What mechanism is located at the engine?

5)What is the function of the generator?

6)What is the starting motor?

7)What happens to a driving pinion?

8)What is the highest position of the piston called?

9)What is the lowest position of the piston called?

10)What is “the combustion space”?

11)Where is the fuel-air mixture compressed?

12)What is the fuel-air mixture compressed by?

13)What is it ignited by?

9. Give synonyms to the following words:

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10. Here are the answers to the questions. Write down the questions.

1)The liquid fuel is mixed with air.

2)The fuel-air mixture enters the cylinder.

3)The generator is located at the engine.

4)The highest position of the piston in the cylinder is called “top dead centre”.

5)The lowest position of the piston in the cylinder is called “bottom dead

centre”.

6)The fuel-air mixture is compressed

7)by the upward movement of the piston.

11.Look through the text again. Make a plan of the text.

12.Compose a short summary of the text using the following expressions:

The text informs/reports. . The text dwells upon ... .

The text runs/comments on ... .

In conclusion it should be noted ... .

Unit IV

The working method of a four-stroke cycle carburetor engine

Let us analyze the working method of a four-stroke cycle carburetor engine, as an example.

With All the carburetor engines, the fuel-air mixture is sucked into the cylinder by the downward movement of the piston. The fuel-air mixture is broken up and partially vaporized in the carburetor; then, it is ignited by an incorporated ignitionsupplying device, the spark plug.

In case of the four-stroke cycle engine, the path covered between top dead centre and bottom dead centre and vice versa is a stroke. Each stroke is accompanied by one-half of a crank-shaft evolution. The complete cycle requires the following four strokes.

Suction stroke: the piston moving downward takes in fuel-air mixture through the open intake valve, while the exhaust valve is closed. Immediately after the piston has reached the bottom dead centre, the intake valve is closed. The first stroke has

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been finished. The crankshaft has turned one-half of a revolution.

Compression stroke: with the valves closed the fuel-air mixture is compressed by the upward stroke of the piston toward top dead centre. The crankshaft has finished one full revolution.

Power stroke: before the piston has reached the upper dead centre, ignition is performed. The compressed fuel-air mixture burns, the gases expand due to the heat of combustion and force the piston go downward. The valves are still closed. The crankshaft has turned one and one half of a revolution.

Exhaust stroke: after it has been finished, the-piston moves upward to the top dead centre and pushes the burned gases out of the cylinder through the open exhaust valve. As soon as the piston has reached the top dead center, the exhaust valve is closed and the intake valve is opened. Now, the crankshaft has completed two revolutions. The next cycle can begin.

Tasks

1. Read and guess the meaning of the following words and phrases:

to analyze, the working method, cycle, fuel-air mixture, the path, top dead centre, bottom dead centre, one-half, revolution, ignition, the gases, force.

2. Give synonyms to the words:

3. Give opposites to the following words:

4. Correct the statements which are wrong (use “false” or “true”).

1. The fuel-air mixture is sucked into the cylinder by the upward movement of the piston.

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2.Each stroke is accompanied by one-half of a crankshaft revolution.

3.The piston moving upward takes in a fuel-air mixture through the closed intake valve.

4.The exhaust valve is opened at this time.

5.During compression stroke the crankshaft has finished two full revolutions.

6.As soon as the piston has reached the top dead center, the exhaust valve is closed and the intake valve is opened.

5. Choose the right Voice of the verb.

1.The fuel-air mixture (sucks, is sucked) into the cylinder by the downward movement of the piston.

2.The fuel-air mixture (is broken, breaks).

3.The path covered between top dead center and bottom dead center (is called, calls) the piston stroke.

4.The complete cycle (is required, requires) the following four strokes.

5.The piston (takes, is taken, are taken) in the fuel-air mixture.

6.The exhaust valve (is closed, closes, closed).

7.The first stroke (has been finished, finishes, finished).

8.The crankshaft (has finished, has been finished).

6. Find the answers to the following questions:

1.Where is the fuel-air mixture sucked into?

2.What happens to the fuel-air mixture in the combustion chamber?

3.What is a stroke?

4.What is each stroke accompanied by?

5.How many strokes does the complete cycle require?

6.Is the exhaust valve closed during the suction stroke?

7.What is the fuel-air mixture compressed by?

8.When is ignition performed?

9.Why do the gases expand?

10.What forces the piston to go downward?

11.When can the next cycle begin?

7.Write out the verbs in Present Simple Active.

8.Write out the verbs in Present Simple Passive.

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9.Write out the verbs in Present Perfect Active.

10.Write out the verbs in Present Perfect Passive.

11.Find in the text the words and phrases with similar meaning:

12. Correct the mistakes in the sentences given below.

1.The fuel-air mixture is sucks into the cylinder.

2.The fuel-air mixture broken up.

3.Each stroke is accompany by one-half of a crankshaft revolution.

4.The piston moves downward takes in the fuel-air mixture.

5.The first stroke been finishing.

6.The fuel-air mixture be compress by the upward stroke of the piston.

13. Give a short summary of the text using the following phrases:

The text deals with ...

We learn from the text that ...

In conclusion it should be noted that ...

Unit V

Cylinders

Cylinders and cylinder heads of the engine are made either of grey cast iron or cast light metal. In general, the combustion chamber is located in the cylinder head to permit an objectionable and continuous machining of combustion space and working surface of the cylinder. In case of valve-in-head engines, the cylinder supports the valves and the valve operating mechanism. In addition, the cylinder head comprises the induction and exhaust ducts.

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Since the working surface of the cylinders is a subject to wear in the course of operation due to the side pressure of the pistons the cylinder block is enlarged. In order to avoid the subsequent replacement of the cylinder block, liners are pressed into the cylinders to be worked in the same way as the original cylinder.

Modern constructions are designed for cylinder liners from the beginning. There are either dry cylinder liners surrounded by a grey-cast iron or light-metal jacket, or wet liners, the centre of which is surrounded by the cooling water.

A copper-asbestos or iron-asbestos gasket is placed between the surfaceground cylinder block and cylinder head. The gasket is required to seal all the holes such as an overflow opening for the cooling water, attachment bolts and the compression spaces from each other.

If a defective gasket is used, the combustion gases will enter adjacent cylinders. Instead of the fuel-air mixture produced in the carburetor, gases from the adjacent cylinders are sucked in during the intake stroke and the mixture ratio becomes, unfavorable. The service life of the engine becomes shorter.

In the gasket is leaky and the cooling water enters the cylinder space there may be serious damages or total destruction of the engine.

Engine control comprises all the parts of an internal-combustion engine controlling the cycle of the strokes. Depending on the type of the control members, a difference is made between valve timing gear and port control (for the two-stroke cycle system only).

Tasks

1. Translate the terms:

working surface, pistons, liner, dry liners, wet liners, cooling water, gasket, to seal, hole, overflow opening, combustion gases, mixture ratio, the service life, leaky, valve timing gear, port control.

2.Write out the terms unknown to you.

3.Find out the attributes to the following nouns:

surface, pressure, cylinder, constructions, liners, iron, jacket, water, opening, water, bolts, spaces, gases, mixture, stroke, ratio, engine.

4.Make a list of words unknown to you.

5.Write out all the verbs in the text in Present Simple Active.

6.Write out all the verbs in Present Simple Passive.

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7.Find out the Infinitive in Passive Voice.

8.Find out the Modal Verb in the text. Define its form.

9.Find out the Participle II and write out them.

10.Find out the verb in Future Simple Active.

11.Make these sentences negative:

1.Modern constructions are designed for cylinder liners from the very beginning.

2.The working surface of the cylinders is subject to wear.

3.The center of liners is surrounded by the cooling water.

4.A copper-asbestos gasket is placed between the surface-ground cylinder block and cylinder head.

5.The gasket is required to seal all the holes in overflow opening, attachment bolts, and compression spaces.

6.The mixture ratio becomes unfavorable.

7.There may be serious damages or total destruction of the engine.

8.Engine comprises all the parts of an internal-combustion engine.

9.A difference is made between valve timing gear and port control.

12. Answer the questions:

1.What can be worn?

2.What can be enlarged?

3.What can be wet and dry?

4.Why is the working surface of the cylinder the subject to wear?

5.What are the liners pressed into the cylinders for?

6.What are cylinder liners are?

7.What are cylinder liners made of?

8.In what case will the combustion gases enter the adjacent cylinders?

9.What may happen if the gasket is leaky?

10.What parts of an internal-combustion engine does engine control comprise?

13. Reproduce the sentences from these prompts.

1. Since ... surface ... is ... to wear in the course of operation due to the ... of the pistons, the cylinder ... is enlarged.

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2.There are either ... cylinder ... surrounded by a ... iron, or wet ... , the center of which is ... by the ... water.

3.The gasket is ... to seal all the holes such as ... for the ... water, ... bolts and the ... spaces from ... .

4.If a ... gasket is ... , ... gases will ... cylinders.

5.The ... life of the ... becomes ... .

6.A difference is ... between ... timing ... and ... control.

14. Fill gaps with correct verb tense.

1.The cylinder block (to enlarge).

2.Liners (to press) into the cylinders.

3.Modern constructions (to design) for cylinder liners from the very beginning.

4.The combustion gases (to enter) the adjacent cylinders.

5.Gases from the adjacement cylinders (to suck in) during the intake stroke.

6.The mixture ratio (to become) unfavourable.

7.If the cooling water (to enter) the cylinder space, there (to be) serious damages of the engine.

15.Make a plan of the text.

16.Compose a short summary of the text using the next phrases:

The text informs about ...

From the text we learn that ... .

It should be mentioned ... .

The text runs about ... .

In conclusion it should be summarized that ... .

Unit VI

Valve timing gear

The valve timing gear of the four-stroke cycle engine operating with vertical valves comprises the following components: camshaft, tappets, valves with springs, spring plates and valve cones .

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In case of the valve-in-head engine the following components are additionally required: the valve push rods and the rocker arms with the rocker bearings. If the camshaft is arranged above the valves, the tappets and the valve push rods are not required.

The port control used for two-stroke cycle engines is based on the opening and closing of ports in the cylinder wall by means of the top or bottom edge of the piston. In contrast to the valve timing gear, this type of control is not requiring any parts additionally to be moved.

Main component of the valve timing gear is the valve. It is a plate-like blocking device equipped with a valve face, valve disk and a valve stem. Opening of the valve is forcibly actuated by lifting its stem via the tappet by the cam of the camshaft. The valve is closed by the valve spring.

The filling rate of the cylinders and the engine are subject to the design and mode of operation of the valve mechanism. In order to achieve a leak proof seal of the valve, the entire actuating mechanism of the valve timing gear must have a clearance. For clearance adjustment, either the tappets or the rocker arms are equipped with adjusting screws or eccentrics. The extent of the clearance is a subject to the degree of heating and the length of the valve stem.

The valve mechanism, with vertical valve arrangement is the most simple, because it is operating with a minimum of components. The camshaft is supported in the crankcase actuates the valve tappet guide in a bushing arranged in the crankcase. The tappet movement is transmitted to the valve stem. The valve stem moves in the valve guide forced into the cylinder block with good fit and is held by the valve spring.

Tasks

1.Read and translate the following words and word combinations. Pay attention to their pronunciation:

gear, valve timing gear, four-stroke cycle engine, camshaft, tappets, springs, plates, cones, push rod, rocker arm, bearings, rocker bearings, edge, device, valve face, actuated, forcibly, via, rate, clearance, seal, adjustment, screw.

2.Guess the meaning of the words and word combinations given below: four-stroke cycle engine, vertical, components, cones, valve-in-head engine, push rod, port control, opening, closing, bottom, top, blocking device, valve face, valve disk, lifting, mode, valve mechanism, actuating mechanism, clearance, eccentrics.

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3.Underline all the verbs in the first passage.

4.Make a list of regular verbs and give their 3 forms.

5.Make a list of irregular verbs and give their 3 forms.

6.Underline all the Participles I and Gerund.

7.Make a list of attributes before the noun determined.

Pay attention to the nouns in the function of attribute. Example: the valve mechanism, intake stroke, power stroke.

8.Make sentences negative and interrogative.

1)The tappets and the valve push rods are not required.

2)Camshaft is arranged above the valves.

3)The port control is based on the opening and closing of ports.

4)The main component of the valve timing gear is the valve.

5)A blocking device is equipped with a valve face, a valve disk and a valve

stem.

6)The valve is closed by the valve spring.

7)The actuating mechanism must have a clearance.

8)The valve mechanism is operating with a minimum of components.

9)The camshaft is supported in the crankcase.

9.Make a list of special terms you have already known.

10.Make a list of special terms unknown to you.

11.Give synonyms to the next words:

to operate, to comprise, components, to require, push rod, top, bottom, edge, device, to equip, to lift, rate, design, entire, screw.

12. Read the text for the second time and find the answers to the next questions:

1)What components does the valve timing gear compose of?

2)What components are required in case of the valve-in-head engine?

3)What is not required if the camshaft is arranged above the valves?

4)What is the port control used for two-stroke cycle engines based on?

5)What mechanism is the main component of the valve timing gear?

6)What does a blocking device look like?