Automobile knowledge

  SPARK PLUG Spark plug is a device to produce electric spark to ignite the compressed air fuel mixture inside the cylinder. The spark plug screwed in the top of the cylinder so that it’s the electrode projects in the combustion chamber. Construction : A spark plug consist of three parts 1.       Centre electrode or insulated electrode. 2.       Ground electrode or outer electrode. 3.       Insulation separating the two electrodes. The upper end of the centre electrode is connected to the spark plug terminal, where H.T cabel from the ignition coil is connected. It is surrounded by porcelain insulator. The lower half portion of the insulator is fastened with a metal shell. The lower portion of the shell has a short electrode attached to one side   and bent in towards the centre electrode, so that there is a gap between two electrode. The two electrode are separated by the insulator. The sea...

  Engine Tuning Engine tuning is more frequently required in modern high compression engine which are more sensitive to variation from specifications than the earlier slow speed low output engines. To maintain an engine at peak performance and economy it must be kept in good condition with all components upto specifications. Often during the engine tuning several conditions will be found which must be corrected to restore the engine to like new condition TUNING PROCEDURE A typical tuning or tune up procedure is given below, which includes visual and mechanical check and also check with instruments. Some of the checks are not related to the engine but should be done for the safety purpose. 1. Loose spark plug start engine to blow out carbon and dirt, shut off engine and remove plug. 2. Test engine compression. 3. If the compression ratio not upto specifications perform engine service that will eliminate the troubles. if the compression is all right re install the spark plug. 4. R...

  Cylinder block . Cylinder block, cylinder head and crankcase these three parts from the foundation and main stationary body of the automobile engines. They serve as support enclosure for moving parts. In modern engines the cylinder block and crankcase from a single casting which gives a rigid structure. The cylinder block may also have a separate crankcase for the crankshaft which is mainly confined to large engines, marine and stationary engines. A separate aluminium crankcase would result in saving the weight as well as enable cheaper and quicker replacement.  1. The cylinder in which the piston slide up and down 2. The ports or opening for the valves 3. The passages for the flow of cooling water The cylinder block is usually made from grey cast iron , and sometimes, with addition of nickel and chromium. Some blocks are cast from aluminium, in which cast iron or steel sleeves are used. For most engines cast iron has been found to be a satisfactory cylinder wall materia...

          FOUR STROKE, DIESEL CYCLE, COMPRESSION IGNITION ENGINE The engine of heavy motor vehicle ( like truck, buses) stationary power plant big industrial units and ships mostly operate on diesel cycle or constant pressure cycle. It was introduced by Dr Rudolph Diesel in 1897. Diesel cycle differs from Otto cycle in one respect. The heat is added at constant pressure instead of at constant volume. Thus, it comprises two adiabatic process, one constant pressure heat addition process and one constant volume heat rejection process. Diesel cycle engines mostly use heavy oils. Diesel oil is the most common. Diesel cycle engine only air is compressed in the cylinder to a high pressure, the temperature of nice compressed air Sufficiently high to ignite fuel. Diesel is injected in the cylinder at the end of compression stroke which itself ignitor new to high temperature of the compressed air. There is no spark plug in diesel engine. In a four stroke diesel cycle, co...

  VALUE TIMING DIAGRAM OF A FOUR STROKE, OTTO CYCLE ENGINE It has already been explained in the operation of four stroke, Otto cycle engine that the inlet valve opens during the suction stroke and the exhaust stroke and the exhaust valve opens during the exhaust stroke. The exact moment at which each of the valves opens and closes with reference to the position of the piston and crank can be show graphically in a diagram. This diagram is known as valve timing diagram. Theoretically, the inlet valve opens exactly at the beginning of suction stroke and closes at the end of the stroke. Both the valves close during power and compression stroke. The exhaust valve opens exactly at the beginning of exhaust stroke and closes at the end of the stroke. The theoretical valve timing diagram for a four stroke Otto cycle engine in shown in diagram. The opening and closing valves with reference to the position of piston and crank shaft during the four strokes are described as follow. 1.  ...

  HISTORY OF THE AUTOMOBILE 1. In 1769, a french Engineer captain Nicholas Cugnot, built the first vehicle propelled by its own Power 2. It was a three wheeler, four-seater vehicle fitted with a steam engine. It attained a speed of about 2 ½ m.p.h. for 15 minutes 3. In1880 , German and French efforts developed an internal combustion engine vehicle, which was used to carry fruits. The present day automotive is the development of this vehicle. 4. In1885 Benz in Germany built a tricycle propelled by an internal combustion engine. 5. In 1885-86, Gottlieb Daimler patented an internal combustion engine in Germany and a year later it was running in a vehicle. 6. In 1895, ChArles E. Duryea and Elwood J.Haynes in America developed experimental automobiles. In this year, Panhard and levassor in France also developed a car which, with minor exception, incorporated the chief features of the automobile as we know it today. 7. In 1890-1895, the European designers were also active in the develop...