Working of 4-stroke petrol engine

    In a four stroke petrol engine one cycle can be taken from four stages they are
  1.Suction stroke
  2.Compression stroke
  3.power stroke
  4.Exhaust stroke

          

       1.Suction stroke or Intake stroke
   During the suction stroke piston moves from top dead centered to bottom dead centered.this time inlet valve is open air fuel mixture from carburettor enter the cylinder. Because the piston move top dead centered to bottom dead centered the air pressure in the cylinder is reduced and air fuel mixture enter the cylinder.The air fuel mixture is highly velocity enter the cylinder.The pistion moves from top dead centered to bottom dead centered one stroke is completed.

             2.Compression stroke

  The second stroke is called compression stroke. This stroke is what perform is include name of stroke. The second stroke piston moves from bottom dead centered to top dead centered .This time the inlet and exhaust valves are closed and piston piston move bottom to top and compressed the air fuel mixture.The end of compression stroke  the air fuel mixture is highly compressed .End of this stroke next stroke is started.
          
            3. Power stroke

      The power stroke is the most important stroke in the every cycle of the petrol engine.the powe stroke is producing power  and this power is used to work other all stroke . At the end of compression stroke the power stroke is strated this time piston  is top dead centered .  spark is produced produced by spark pluge and burned the fuel and high pressure is developed . This pressure is pushed the piston to  bottom dead centered gives a power output. Inlet and exhaust valves are closed during this process

           4.Exhaust stroke

   This is the last stage of one cycle of petrol engine .Piston move from bottom dead centered to top dead centered and exhaust valve is open and inlet valve is closed .Moment of piston exhaust gas is escape throw the exhaust valve

Technical word using petrol engine and it’s meaning

a.Top dead centered :      Position of piston at top of the cylinder it means highest position of piston inside the engine

b.Bottom dead centered :    Position of piston at bottom of the cylinder it means lowest position of piston inside the engine

c.Cylindrical bore :   The inside diameter of the cylinder is known as cylindrical

d.Stroke :       The motion of piston from one dead centered to other

e.Stroke length:     The distance between top dead centered and bottom dead centered

f.Swept volume :    The volume of the cylinder in between top dead centered and bottom dead centered

g.Clearence volume :  The volume of the cylinder in between top dead centered and cylinder head