The vehicle’s fuel supply system includes several components that are connected to the fuel and the carburettor. These items include the fuel tank, pump, filter, lines, injector, carburettor and gauge. While these items are the same across various systems, there are differences in how they work, depending on the type. So, do you need a fuel test? Here is a quick look at different fuel systems to help you decide.
Gravity Feed Fuel Supply System
The gravity feed system is common with small vehicles such as bikes, two-wheelers and quads. In this design, the carmaker mounts the fuel tank at the highest position. Then, the fuel is fed into the carburettor’s float chamber by the use of gravity.
This system is quite simple, cheap to produce and has very few issues. However, the tank should always be placed over the carburettor for this system to work. This would mean that the vehicle would have to use smaller components or have a deeper bonnet to accommodate such a design.
Pressure Feed System
The pressure feed system makes use of a pressurised tank that is hermetically sealed to ensure that it is airtight. The engine exhaust or a separate air pump creates the pressure in the tank. However, before starting the engine, you need to hand prime your pump.
This action creates pressure which forces the fuel to flow to the carburettor. Although there is always a risk of pressure leakage, you can place the fuel tank in any location in the vehicle and still get the fuel to the carburettor. This is an advantage, as the car can be designed without affecting the fuel system.
Vacuum System
A vacuum system uses suction pressure to bring the fuel from the main tank to the auxiliary one. From the auxiliary tank, the fuel flows to the carburettor via gravity. You can place the main tank at any location in the vehicle, but the auxiliary tank should always be above the carburettor.
This system creates a few issues for the car manufacturer. First, there must be enough space to house two tanks at once. There is also a chance that the suction system may fail. The gravity system is also likely to fail. This type of fuel system is now obsolete.
Pump Feed System
This system is popular with many modern vehicles. It uses a steel pipe for supplying petrol to the fuel pump and then pumps the same to the carburettor float chamber through the use of a flexible pipe. If you are using a mechanical pump, then the engine camshaft provides it with the drive. Therefore, such a system is connected to the engine.
Electrically operated pumps can be located at any point of the vehicle. Some fuel manufacturers even place it inside the fuel tank to eliminate the risk of a vapour lock. This system helps utilise small spaces in a vehicle to increase efficiency.
Fuel Injection System
The fuel injection system is the most successful and popular in modern vehicles. Instead of a carburettor, carmakers use a petrol injection system to deliver the proper mix of air and fuel to all cylinders. It also comes with an injector nozzle to atomize the fuel before it is delivered into the air stream.
In this system, car manufacturers use separate fuel injectors for each cylinder. The mixture load and speed are controlled mechanically or by the use of an electronic system. This enhances the accuracy of the system. Fuel injection systems develop high power and are quick to start. They also have low specific fuel consumption.
The fuel injection systems come in several types. Here are common ones.
Single-Point Fuel Injection
This system is called a throttle-body injection. It uses a common fuel injector for all your cylinders in the combustion chamber. Here, the fuel is sprayed onto every cylinder at the same time. While this system has advantages over the carburettor system, it may affect performance at high Rpm, which causes a rough ride.
Multi-Point Fuel Injection
This system is also called a port injection system. Each cylinder gets an injector at the front of the inlet. This system is more precise as each injector uses a precise volume of fuel and reduces the possibility of fuel condensation.
Other fuel injection systems include sequential and direct fuel injection.
Thomas Hyde is an advocate for technological innovation and high-octane competitions, embodying his passion through Dead Blow, a premier website dedicated to the dynamic universe of Battle Bots, Robot Wars, and home-built combat robots. With a rich background in engineering and a lifelong fascination with robotics, Thomas created Dead Blow to serve as a hub for enthusiasts and builders alike.
