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Simply put, an automobile engine is a motor that converts thermal energy to mechanical work in order to propel an automobile. The engines commonly used in automobiles are internal combustion engines wherein fuel viz. gasoline and air mixture burns in an enclosure known as the combustion chamber. Consequently, this blast or chemical reaction produces gases at high temperature and pressure. As these gases expand with force, their energy is used to perform mechanical work to drive the vehicle.

The functioning of an engine is cyclic. Different sets of engine components must move in a controlled and a coordinated fashion to keep a vehicle in motion. The set of repetitive movements is called the engine cycle. A typical 4-stroke engine cycle entails the following stages or strokes:

1.Intake stroke: Wherein air and fuel are drawn in to the combustion chamber.


2.Compression stroke: In this stage the vaporized fuel and air are compressed and then ignited.

3.Combustion stroke: It is a phase in which the fuel burns releasing energy and pushing the piston.

4.Exhaust stroke: This stage is marked by expulsion of waste gases (exhaust) and heat.

Engines of cars and trucks involve several such processes occurring one after the other depending upon the type of engine viz. 4-cylinder, 6-cylinder engine, or 8-cylinder engine etc. Usually, the more the number of cylinders, greater is the power generated.

A number of essential engine parts enable the automobile engine to work well. For, instance a typical four-stroke engine's key components include connecting rods, pistons, crankshaft, spark plugs, valves, crankpins, camshafts, cylinders, etc.

Automobile Engine Components

Components and subsystems that are the bedrock of an engine are numerous. Some common ones are described below.

Camshaft

A camshaft is an automotive part that operates the poppet valves (the valves used to open and close the intake and exhaust ports within the cylinder head). Structurally, it is made up of a cylindrical rod and a number of oblong lobes or cams jutting out from it. There's a separate cam for each of the valve. As the cams move that force open the valves when the press on them and also close them by a similar mechanism.

Crankshaft

Also nicknamed as the crank, a crankshaft converts the to-and-fro motion of the piston into rotary motion so as to transfer the power to the transmission. A typical crankshaft comprises crank throws/crankpins and bearing surfaces to which the connecting rods from cylinders are attached.

Connecting rod

In an automobile engine the connecting rod also called a conrod joins the piston to the crank or crankshaft and aids in transmitting the force and motion from the piston. Subjected to heavy stress, conrods are often made of steel, or Aluminum, or Titanium.

Cylinder Head

The cylinder head is positioned at the top of the engine block is the and contains a platform containing part of the combustion chamber as well as the location of the valves and sparkplugs. In case of an overhead valve head, the top half of the cylinder head houses the camshaft or another mechanisms viz. rocker arms and pushrods that aid in transfer rotational motion from the crankshaft to linear motion used to operate the valves.

Crankcase

In an automobile engine, the crankcase refers to the housing meant for the crankshaft. A crankcase is the largest cavity in the engine, which is separated from the cylinders by the reciprocating pistons. Aside from protecting the crankshaft and connecting from foreign objects, based on the type of engine it accomplishes other functions as well.

Engine Block

Also known as the cylinder block, it is a machine casting or at times a compilation of modules comprising cylindrical holes for housing the pistons of an engine, or for a similar devices such as pumps. Complicated in design, it forms the bedrock for mounting of other critical engine parts including crankcase, cylinder head, drive housing, engine mounts, engine ancillaries, passages for coolants, lubricants, etc.

Piston

A piston is an important component of an automobile engine. Positioned inside a cylinder it is made gas-tight by means of piston rings. Its purpose is to transfer the force of expanding gas in the cylinder to the crankshaft through a piston rod and/or connecting rod.

Buying Tips

You can ensure quality automotive part supplies through the following buying tips.

1. Always prefer new auto parts instead of used ones.

2. Choose your suppliers carefully, establish a reasonable level of trust towards a supplier, through referrals, testimonial, or certifications.

3. Be wary of suppliers offering products at extraordinarily low prices.

4. Ensure the specifics of the products you require from the supplier, before placing the order, a sample inspection is often the best way to do it.

5. You need to understand the terms and conditions including warranties and guarantees associated with the supplies you order.

Industry Overview

Companies world over, involved in the design, development, manufacture, marketing and sale of motor vehicles constitute the automotive industry. Automotive industry is large and growing. In 2007, over 73 million motor vehicles, including cars and commercial vehicles were produced around the world. Of which 22.9 million were produced in Europe, 19.4 million in USA and Canada, 4.4 million in Latin America, 21.4 million in Asia-Pacific, 1.4 million in Africa and 2.4 million in the Middle East.

Off late, while the markets in North America and Japan haven't grown fast, the emerging markets of South America and Asia, including Russia, Brazil and China have witnessed remarkable growth.

Automobile engines are at the heart of the industry and several trends will drive the production of automotive engines of the future. Responding to the various social, economic, environmental, political and technical factors, the engine design and development is geared towards fuel efficient and low emission engines. Additionally, engines driven by alternative fuels viz. hybrids, CNG, Hydrogen, Electricity are gaining ground and are attracting attention. The future of engine design will also be determined by need for building sustainable transport systems.