Component identification

Component identification

Section 1: Major Components

  • An engine’s major components include the cylinder block and cylinder head.
  • The cylinder block houses the pistons, connecting rods, and the crankshaft, among other components.
  • The cylinder head contains the valves, spark plugs, and often the fuel injectors.

Section 2: Pistons and Connecting Rods

  • Pistons have a cylindrical shape and move within the cylinders of the engine. They are connected to the crankshaft via the connecting rods.
  • Note that the upper surface of a piston is called the crown, while the lower part is known as the skirt.
  • Connecting rods are linked to the pistons via piston pins, allowing the transfer of motion from the pistons to the crankshaft.

Section 3: Cylinder and Crankshaft

  • The cylinder is the space in which the piston moves and where the fuel-air mixture is ignited to generate power.
  • Each cylinder is sealed at one end by the cylinder head and at the other by the crankcase, forming a gas-tight space.
  • The crankshaft is located within the crankcase and is used to convert the up and down motion of the pistons into rotational motion.

Section 4: Valves, Spark Plugs and Injectors

  • Valves control the flow of the air-fuel mixture into the cylinder (intake valve) and the removal of exhaust gases (exhaust valve).
  • Spark plugs ignite the compressed air-fuel mixture within the cylinder, initiating combustion, which creates a ‘push’ on the piston.
  • Fuel injectors spray fuel into the cylinder or the intake manifold in a precise, metered amount.

Section 5: Engine Auxiliary Components

  • Auxiliary components of an engine include the alternator, starter motor, water pump, oil pump, and distributor cap.
  • The alternator generates electricity to power the ignition system, lights, and other electrical accessories while the engine is running.
  • The starter motor turns the crankshaft to initiate the combustion process.
  • The water pump circulates coolant through the engine to disperse heat.
  • The oil pump circulates lubricating oil throughout the engine to reduce wear and tear on moving parts.
  • The distributor cap distributes the voltage from the ignition coil to the correct cylinder’s spark plug.

Remember, being able to identify and understand the function of these key engine components is essential for anyone working on or with spark ignition engines.