If your car has a gasoline or petrol engine, you know what spark plugs are. These are crucial parts of a combustion engine system. Your vehicle won’t be able to move a bit without these tiny components. But do you ever thought about how a spark plug works? Well, you will get your answer today! In this article, I am explaining the working process of spark plugs. So, keep reading.
Table of Contents
Components of A Spark Plug
If you want to know the detailed working process of spark plugs, you must know about all the components of a spark plug first. A fresh spark plug has these components.
- Center Electrode
- Hex Nut
- Ground electrode
Structure of Spark Plugs
Starting from the top, the bare metal tip is the terminal connection. This is where the spark plug wires connect with the plug. A central electrode goes from the terminal connected to the bottom of the plug just below that. Also, a resister lies in the middle of the central electrode. The central electrode can’t be seen outside since it is thickly coated with porcelain insulators.
The very outer portion is the nut layer that basically contains the nut thread and the hex head. It hides half of the plug’s insulator covering. At the bottom, the end tip of the central electrode can’t be seen. Lastly, a ground electrode that extends from the nut housing bends underneath the central electrode. It has a measured gap between the electrodes. Lastly, a gasket between the insulator and the housing prevents combustion gases from leaking.
How do spark Plugs work in A car?
In a combustion engine, spark plugs ignite the fuel-air mixture inside the piston housing in rhythm. It eventually moves the piston cylinder in the engine and rolls the wheels. It all starts from the terminal connection, where a very high voltage electric pulse is sent through a connection wire known as a spark plug wire. This voltage may be between 20,000V to 40,000V.
This high-voltage current then transmits to the central electrode. The resister, however, emits electrical noises which generate during sparking. Apparently, this resister stops electrical interference with other electrical components of your car. However, the current then reaches the end tip of the central electrode. Now the high voltage jumps the gap to go reach the ground electrode to complete the circuit. This jump generates a small but strong arc.
This arc creates a small but strong inside the piston housing and creates high pressure. Now since the piston housing is completely sealed when the piston is in the up position, the piston has no choice but to go down with the pressure. It eventually rolls the wheels. The spark plug continuously does this process and keeps the vehicle rolling.
Few Things about spark Plugs
- Spark plugs have shorter service life than most other engine components.
- The gap between the two electrodes is very important. The bigger the gap, the higher voltage it needs.
- Spark plugs with a longer “reach” than required can get banged by the piston.
- Almost all vehicles use cold spark plugs.
- The diesel engine doesn’t have spark plugs.
A Quick Overview
A spark plug is a crucial component of a gasoline engine, as it ignites the fuel-air mixture within its combustion chamber. The spark plug consists of several parts, including the center electrode, the ground electrode, and the insulator. The center electrode is part of the plug that protrudes into the combustion chamber, while the ground electrode is at the plug’s base.
The spark plug generates an electrical spark between the center and ground electrodes. This spark ignites the fuel-air mixture within the combustion chamber, generating the engine’s power. The electrical energy required to generate the spark is supplied by the vehicle’s ignition system, which typically consists of a coil, distributor, and sparks plug wires.
When the engine runs, the ignition system sends a high-voltage electrical charge to the spark plug. This charge jumps the gap between the center and ground electrodes, ionizing the air and creating a plasma channel. This plasma channel is extremely hot, reaching temperatures up to 60,000 degrees Fahrenheit, sufficient to ignite the fuel-air mixture.
The design and construction of spark plugs have evolved over the years, with modern spark plugs incorporating advanced materials and features to improve their performance and longevity. However, their basic principles remain the same, making spark plugs a critical component of gasoline engines.
Learning how a spark plug works may give you a clearer view of an engine’s internal functions. The spark plug function is a little complex. But you will understand the whole spark plug working principle if you read the article attentively. Furthermore, learning about engine components always helps in emergencies. I hope this article has fulfilled all your queries about spark plugs.