Every wonder what makes a car engine run? We get in our cars every day; keys in the ignition, power on, crank up the tunes, and off we drive. But have you ever thought about how this thing actually works? There are so many factors going on inside your engine, I bet you’d be surprised how quickly everything works together to help you accelerate!
Car Basics 101: How Your Engine Works!
Part 1: Internal Combustion
The first thing you need to know about your car is that a car engine is an internal combustion engine. What does that mean? Internal Combustion Engine means combustion takes place… internally; running off a mixture of gasoline and air. According to an article from How Stuff Works, “the easiest way to create motion from gasoline is to burn the gasoline inside the engine.” Hence internal combustion! So when you add gas to your car, once it ignites via starting your car and pushing the pedal, that amount of energy created will move your car. Seems pretty simple..?
Oh! But there is so much more going on!
Part 2: Types of Engines & Parts
To begin, we need to know what kinds of engines are out there and specific parts that work together to move your car. Most engines used today are four-stroke engines. However, each engine is identified by the number of cylinders and the form they take. In-line engines are arranged in a row, consisting of 3,4,5, or 6-cylinders. The “V” type engine is commonly used for V6, V8, V10, or V12 arrangements. Lastly, there are “Flat” engines, using 4 and 6-cylinders, most popular in Subaru, Porsche, and some Ferraris.
Now, each cylinder contains pistons that move up and down inside the cylinder. These are connected through rods to a common crankshaft. Your crankshaft will turn as the pistons move up and down while connecting to the cylinders. On the top of your cylinders, the “cylinder head” contains valves for intake and exhaust. These open and close with the help of the camshaft. I know, how confusing! Camshaft and crankshaft…? Your camshaft lobe will push against the valves and move them up and down, pushing the valves open. Remember, the engine has two valves per cylinder for intake and exhaust; or for what comes in and what goes out.
Part 3: How Your Engine Works
Now that we know the basics and terminology, let’s put everything into perspective! The information below explains the process of just one cylinder, for the sake of time, but remember each engine has a set amount of cylinders to help it run. So take this process and multiply it by your engines’ cylinders to understand the whole process!
Intake, compression, power, and exhaust are the four strokes to make your engine work. Basically, a piston will travel down the intake stroke, up the compression stroke, down the power stroke, and up on the exhaust stroke. Keep reading for a more in-depth explanation!
The piston starts moving down on the intake stroke, adding that gas-air mixture I mentioned above, in order to be compressed. Moving up through the compression stroke, the gas-air mixture is compressed into a specific amount and released. This ignites the spark plug fires, pushing the pistons down the cylinder again at a massive amount of force, turning the crankshaft (similar to what I mentioned above). When the piston is at the bottom of the cylinder, the exhaust valve opens to expel the burned gas into the exhaust system. At an even greater force, the piston shoots up to the top of the cylinder, pushing all of the exhaust out before closing the valve and starting the whole four-stroke process over again. (It is a little more complicated than that so if you want to learn more, check out this awesome article)
Phew.. those pistons work hard! And the process above is for only one cylinder! Imagine how fast your engine works to move 6, 8, 12-cylinders?! Pretty cool to think about how powerful your car engine is!
Now besides all the camshafts, crankshafts, pistons, cylinders, etc. you have oil, engine cooling, balance, and other fuels to help your car move smoothly and effortlessly. Which we will save for a later chapter! I am sure your brain is still trying to wrap itself around the idea of this tiny piston being shot up and out with so much force! If the wording is a little much, check out this picture to help guide you through the whole process. I bet you will look at your car differently the next time you put that key in the ignition!