Engine Systems and Components Ag Powers

Objectives Identify the categories of internal combustion engine systems in class notes. Identify the components of the primary or compression systems. Describe the components of an engine’s operating system.

Categories of internal combustion engine systems Primary system Operating systems Accessory systems

Primary System Creates the engine compression and converts the energy of combustion to mechanical energy. Also referred to as the compression system.

Operating Systems Perform other engine functions. Engine will not operate without operating systems. Also referred to as auxiliary systems. Examples: electrical system, cooling systems, etc.

Accessory Systems Not necessary for engine operation. When they fail, the engine is still operable. Example: power steering system

Components of Primary System Piston piston rings Cylinder Head gaskets Cylinder head Valves Intake and exhaust Valve springs Spring retainers Valve guides Camshaft

Components of Operating System Air intake system- functions to provide a source of clean air necessary for the combustion of the air-fuel mixture. Air cleaner- filtering device located on the outside of the engine. Carburetor- provides fuel and air to the engine in correct proportions and volume.

Components of Operating Systems Fuel System- Delivers clean and adequate amounts of fuel to the cylinder. Fuel tank Fuel filter- acts as a cleaner for the fuel that passes through it. Fuel pump- ensures that an adequate amount of fuel under the correct pressure is distributed throughout the rest of the system. Fuel injection systems- inject fuel into the combustion chamber Mechanical fuel injection systems- use mechanical type pumps Electronic fuel injection systems- use electrically operated injectors

Components of Operating Systems Exhaust system- Removes the exhaust gases and particles from the combustion chamber. Manages engine noise and heat transfer. Exhaust manifold Exhaust pipe Muffler

Components of Operating Systems Engine cooling system- Manages the heat produced by the combustion of the air-fuel mixture. Allows the engine to reach its optimum operating temperature and to maintain that temperature under varying conditions. 2 basic types: Liquid cooling system Air-cooled system

Engine Cooling Systems Liquid cooling system- Uses a liquid to transfer heat from engine components to the surrounding air. Radiator- heat transfer device that acts as a cooling and storage area for the liquid combination of water and antifreeze. Water pump- mechanical device that forces the coolant to flow through the system. Thermostat- flow control valve that regulates temperature inside an engine by opening and closing. Additional components of a liquid cooling system: radiator cap, water jacket, fan, fan belt, temperature gauge

Engine Cooling Systems Air-cooled system- transfers the heat of the engine components directly to the surrounding air. Common on small gas engines. Fins- used to increase the surface area in contact with the air so that engine heat can be transferred more efficiently. Shroud- engine cover that directs cooling air across the engine fins. Fan- force air through the engine cooling system.

Components of Operating Systems Ignition system- Starts the combustion of air-fuel mixture. Compression ignition system- No unique parts; part of the compression system Spark ignition system- Uses a high voltage electrical spark to ignite the compressed air and fuel mixture in the combustion chamber. 2 types: Magneto-type ignition systems Battery-type ignition systems

Spark Ignition Systems Magneto- type ignition systems- use magnets and coils to generate electrical pressure to arc the spark plug. Flywheel magnet creates a magnetic field which cuts across the armature and coil assembly as the flywheel rotates, inducing voltage into the primary circuit.

Spark Ignition Systems Battery-type ignition system- Uses the energy from a battery and/or alternator to create the ignition spark.

Components of Operating Systems Lubrication system- Keeps internal engine parts coated with oil to: Reduce friction Enhance cooling Seal internal engine components Clean internal parts Basic components Oil filter Pressure regulator Oil pans Oil pump

Components of Operating Systems Starting system- Used to turn the engine crankshaft until the engine starts. Manual starting systems- Common on small gas engines Manually turning the crankshaft. Rope starter Electrical starting systems- Solenoid-type switch controls the correct amount of voltage going to the starter. Flywheel-