All semi-trucks get power from the engine by the process of internal combustion. They all need an ignition source to ignite the fuel. Spark plugs are small devices that produce fire for explosions.
How Many Spark Plugs Does a Semi-Truck Have? A semi-truck can have one spark plug for each cylinder. They can have six or eight plugs, and trucks with gasoline engines have them. Regular inspection and cleaning is the key to prolong its life. You can replace these every 35000 to 100000 miles and it can cost between $20 to $250.
More than 90% of the semi-trailers have diesel engines, while only 10% run on gasoline or petrol engines. Some of the gasoline trucks are converting to diesel engines due to their better performance and fuel efficiency.
What is the function of the spark plug in a semi-truck?
We all know that the semi-truck engine works on the principle of combustion. It needs a lightning or igniting source to burn the fuel and air mixture. The burning of fuel produces the energy necessary to drive the vehicle.
Spark plugs, as the name indicates, produce a spark in the combustion chamber. The fire ignites the fuel and air mixture within the combustion chamber.
It consists of a central electrode and the ignition coils. The ignition coils are separated from the central electrode using an insulator. One side of the plug protrudes into the combustion chamber to deliver the fire.
The ignition system should deliver a high-voltage current inside the electrode to produce the lightning. The electrical spark then travels towards the fuel and air mixture to produce an explosion. The heat energy produced is converted into mechanical energy to turn the wheels.
Do all semi-trucks have spark plugs?
Semi-trucks are different from other automobiles in many aspects. The manufacturers have used more advanced technology to construct all the components of such big vehicles.
The majority of semi-trucks are equipped with diesel engines, and only some of them have gasoline engines. The spark plugs are present only in the gasoline engines. They are not a part of the diesel engine.
Heavy trailers with diesel engines are equipped with glow plugs rather than spark plugs. The diesel engine uses compression ignition and does not require a fire to ignite the fuel.
The air taken for the air intake system is compressed at high pressure, which raises its temperature enough to produce an explosion in the combustion chamber of the engine.
Number of spark plugs in semi trucks
A spark plug is a small and crucial component of any vehicle. Their number in petrol or gas-powered engines varies depending upon the model of the truck.
The total number depends upon the total number of cylinders present in the engine. One spark plug is allocated for one cylinder. They are present on the head of the cylinder. So in a six engine cylinder, the number of spark plugs is also six.
The number of ignition plugs in a V8 or engine with eight cylinders will be eight. All these plugs produce fire continuously to produce energy.
If one of them is faulty or broken, the rest of the plugs will be sufficient to produce the explosion. But if more than three plugs are damaged, the engine will be difficult to start. But some trucks can start even with one functioning spark plug.
The number of glow plugs also depends upon the number of cylinders. There is one glow plug for one cylinder. So, a diesel engine in a semi-truck can have 4 to 6 glow plugs. Some new models can have up to 10 glow plugs in them.
Difference between a spark plug and a glow plug
The most obvious answer to this question is that spark plugs are present in gasoline engines, while glow plugs are present in diesel engines. However, contrary to their similar function, they differ from each other in many aspects.
They produce a massive spark by receiving high voltage current from the ignition system. While the glow plugs electrify the heating element and emit a visible light. A diesel truck can start without a glow plug in warm weather.
These plugs are required in cold weather and other unfavorable conditions. While they have to fire the electricity continuously to drive the vehicle. Glow plugs have a short warming time and can cause the temperature to be 1200 to 1300 degrees Celsius in a few seconds.
At the same time, spark plugs take longer to deliver the required heat and temperature inside the combustion chamber.
How to maintain a spark plug in a semi-truck?
Spark plugs are the most durable component of a semi-truck. They can last for a long period without any problem. But daily wear and tear can also cause it to get into trouble. Any fault in it can make it cause many issues in the engine and vehicle.
Misfiring and difficulty in starting the engine are signs of damage in these ignition components. You can maintain their performance by following some safety tips.
Regular inspection and cleaning is the key to maintaining such tiny components. Regularly inspect it for build-up of dirt and debris. The presence of any corrosion or crack in the metal or electrode should also be discouraged.
Clean all the dirt and filth from all its parts to maintain it.
How often to replace a spark plug in a semi-truck?
It is difficult to repair a worn-out plug. In such conditions, it is better to replace them. Ideally, a spark plug can last for 35000 to 100000 miles.
Some manufacturers recommend changing them more frequently after every 40000 miles. You should replace them after every 9 to 12 months. Some of them can last longer than that.
The lifespan of these components depends largely on the driving habits of the driver. The road condition and acceleration and deceleration can also impact their performance.
The cost to replace the spark plug in a semi-truck
These tiny ignition sources get damaged due to misfiring and lose their ability to produce fire. In such a case, you have to replace it with a new one. All of us must have an idea of how much does it cost to get this replacement done.
The cost to replace spark plugs differs greatly depending on the quality of the product. It also depends upon the number of plugs to replace in an engine.
On average, the cost of a single plug varies from $10 to $40.Some higher-quality products can be more expensive. The labor cost to install a new plug in a semi-truck depends upon the area of the country.
Replacing a plugin in big cities like New York is more costly than in other areas. The average labor cost to replace it varies from $20 to $200.The total replacement cost varies from $20 to $250 for a semi-truck.
The cost will be higher if you get help from a professional mechanic. The cost to fix filthy plugs varied between $100 to $200.But you can save this money by cleaning these components by yourself.