The fuel is ignited causing a controlled explosion. Ignition stroke: Also known as the power or combustion stoke. Fuel is injected shortly before the piston reaches the top of cylinder. The piston moves downwards, drawing air into the cylinder, via air inlet valves.Ĭompression stroke: The air inlet valves close, and the piston moves upwards compressing the air within the cylinder. Suction Stroke: Also known as the induction or intake stroke. The strokes are:Īnother way to remember the strokes and their order is to change the wording to:īelow is a brief summary concerning what occurs at each stage of the combustion cycle: The below video is an extract from our Internal Combustion Engine Basics Online Video Course.Ī four stroke engine requires four strokes to complete one combustion cycle.

Note: The type of engine shown in this 3D model utilises direct fuel injection with common rail fuel injectors.

For example, common rail engines employ different engine parts compared to non-common rail engines.Įnjoying this article? Then be sure to check out our Internal Combustion Engines Video Course! The course has a quiz, handbook, and you will receive a certificate when you finish the course. Enjoy!Ĭommon four stroke engine components include:Īccess the below 3D model if you would like to learn all of an engine's main components and some engine terminology. Four stroke engines may be fired on many different fuels, including gasoline/petrol, diesel, gas ( methane) and bio-oils (to name a few fuel types).įour stroke engine designs vary, so the number and type of components used per design also varies. Likewise, if the piston moves from the top of the cylinder to the bottom, this is also called a stroke.Ĭompared to two stroke engines, four stroke engines have more components and weigh more, but are more efficient. For example, when the piston moves from the bottom of the cylinder to the top, this is called a stroke.

One stroke is defined as the maximum distance a piston moves when traveling from the top of the cylinder, to the bottom of the cylinder, or vice versa. there is one stroke for each of the suction, compression, power, and exhaust stages. It’s called a four-stroke combustion engine because there are four strokes to one combustion cycle. Each of a four stroke engine's strokes is used for one stage of the combustion cycle i.e. Four stroke internal combustion (IC) engines have been used for over 100 years and their design has not changed significantly since this time.

4 stroke si combustion tempature