powerpoint ® presentation chapter 4 small engine fundamentals four-stroke cycle theory four-stroke...
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PowerPoint® PresentationPowerPoint® Presentation
Chapter 4Chapter 4Small Engine FundamentalsSmall Engine Fundamentals
Four-Stroke Cycle Theory • Four-Stroke Cycle Engine Operation • Engine Components and
Functions • Small Engine Systems • Compression Systems • Fuel Systems •
Ignition Systems • Lubrication and Cooling Systems • Governor Systems • Electrical
Systems • Braking Systems
Four-Stroke Cycle Theory • Four-Stroke Cycle Engine Operation • Engine Components and
Functions • Small Engine Systems • Compression Systems • Fuel Systems •
Ignition Systems • Lubrication and Cooling Systems • Governor Systems • Electrical
Systems • Braking Systems
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
Gasoline-powered four-stroke cycle engines typically power lawn mowers, snow throwers, lawn and garden tractors, and many other types of outdoor power equipment.
Gasoline-powered four-stroke cycle engines typically power lawn mowers, snow throwers, lawn and garden tractors, and many other types of outdoor power equipment.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
Small engines are designed to perform simple tasks with specific types of outdoor power equipment.
Small engines are designed to perform simple tasks with specific types of outdoor power equipment.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
A four-stroke cycle engine completes five events in one operating cycle, including intake, compression, ignition, power, and exhaust events.
A four-stroke cycle engine completes five events in one operating cycle, including intake, compression, ignition, power, and exhaust events.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
An intake event is an engine operation event in which an air-fuel mixture is introduced to a combustion chamber.
An intake event is an engine operation event in which an air-fuel mixture is introduced to a combustion chamber.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
A compression event is an engine operation event in which a trapped mixture of air and fuel is compressed inside the combustion chamber.
A compression event is an engine operation event in which a trapped mixture of air and fuel is compressed inside the combustion chamber.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
An ignition event is an engine operation event in which a charge is ignited and rapidly oxidized through a chemical reaction to release heat energy.
An ignition event is an engine operation event in which a charge is ignited and rapidly oxidized through a chemical reaction to release heat energy.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
A power event is an engine operation event in which a compressed charge is ignited and hot expanding gases force a piston head away from a cylinder head.
A power event is an engine operation event in which a compressed charge is ignited and hot expanding gases force a piston head away from a cylinder head.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
An exhaust event is an engine operation event in which spent gases are removed from the com-bustion chamber and released to the atmosphere.
An exhaust event is an engine operation event in which spent gases are removed from the com-bustion chamber and released to the atmosphere.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
Basic small engine components are used for starting, running, and stopping the engine.
Basic small engine components are used for starting, running, and stopping the engine.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
Valve location determines whether an engine is an L-head or overhead valve engine.
Valve location determines whether an engine is an L-head or overhead valve engine.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
A piston acts as the movable end of the combustion chamber by using the forces and heat created during engine operation.
A piston acts as the movable end of the combustion chamber by using the forces and heat created during engine operation.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
Piston rings provide a seal between the piston and the cylinder bore and commonly include a compression ring, wiper ring, and oil control ring.
Piston rings provide a seal between the piston and the cylinder bore and commonly include a compression ring, wiper ring, and oil control ring.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
A crankcase houses and supports the crankshaft of an engine.
A crankcase houses and supports the crankshaft of an engine.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
A typical small engine fuel system includes a fuel tank, fuel pump (on some models), fuel filter, carburetor, and fuel line.
A typical small engine fuel system includes a fuel tank, fuel pump (on some models), fuel filter, carburetor, and fuel line.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
A carburetor provides the required air-fuel mixture to a combustion chamber based on engine operating speed and load.
A carburetor provides the required air-fuel mixture to a combustion chamber based on engine operating speed and load.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
A throttle plate is used to regulate the flow of the air-fuel mixture to an engine, while a choke plate is used only to assist in cold starting.
A throttle plate is used to regulate the flow of the air-fuel mixture to an engine, while a choke plate is used only to assist in cold starting.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
An ignition system includes multiple magnets, an ignition armature, a spark plug lead, and a spark plug.
An ignition system includes multiple magnets, an ignition armature, a spark plug lead, and a spark plug.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
Breaker points control the flow of electricity to other parts of the ignition system circuit.
Breaker points control the flow of electricity to other parts of the ignition system circuit.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
A solid-state ignition system has a solid-state transistor in the ignition armature.
A solid-state ignition system has a solid-state transistor in the ignition armature.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
The lubrication system and its engine oil absorb heat energy and transfer it to the aluminum cylinder block. The cooling air can then absorb the heat energy from the aluminum and transfer it into the atmosphere.
The lubrication system and its engine oil absorb heat energy and transfer it to the aluminum cylinder block. The cooling air can then absorb the heat energy from the aluminum and transfer it into the atmosphere.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
A governor system is an engine system that maintains a desired engine speed regardless of the load applied to the engine.
A governor system is an engine system that maintains a desired engine speed regardless of the load applied to the engine.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
A mechanical governor uses the gears and flyweights inside a crankcase as speed-sensing devices to detect changes in a load and adjusts the throttle accordingly.
A mechanical governor uses the gears and flyweights inside a crankcase as speed-sensing devices to detect changes in a load and adjusts the throttle accordingly.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
A pneumatic governor uses a movable metal or plastic air vane as a speed-sensing device by registering the change in air pressure around a rotating flywheel.
A pneumatic governor uses a movable metal or plastic air vane as a speed-sensing device by registering the change in air pressure around a rotating flywheel.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
A small engine electrical system typically consists of an alternator, rectifier, regulator, and 12 V battery.
A small engine electrical system typically consists of an alternator, rectifier, regulator, and 12 V battery.
Chapter 4 — Small Engine FundamentalsChapter 4 — Small Engine Fundamentals
An electrical system can be set up to produce either alternating current (AC) or direct current (DC).
An electrical system can be set up to produce either alternating current (AC) or direct current (DC).