Every internal combustion engine vehicle depends on its fuel pump to supply fuel from the reservoir to the engine at the necessary pressure. Engine operation becomes impossible when the fuel pump malfunctions. Automotive fuel system diagnosis and maintenance heavily rely on learning about different fuel pump types alongside their operation methods.
As engine demands have increased in modern automotive development, the fuel pump technologies have also advanced into multiple design options which support different vehicle types and operational requirements.
Fuel pump technology within the automotive field has made major progress because manufacturers seek both improved efficiency alongside better reliability and performance capabilities. Osias is the major manufacturer of potent fuel systems including this vital component.
The EP381 electric fuel pump stands as their flagship product due to its powerful construction and dependable output of pressure requirements. The company delivers customized fuel delivery solutions beyond automotive applications to serve specific needs in industrial sectors.
Mechanical Fuel Pumps
With respect to engine operation, mechanical fuel pumps were once the standard in carbureted engines. Most times, they mount on the engine block and work with the camshaft of the engine. During the rotation of the camshaft, the eccentric lobe pushes against a lever arm on the pump.
Such movement creates a vacuum, sucking fuel from the tank into the chamber of the pump. The return of the lever arm serves to push the fuel through an exit valve towards that of a carburetor.
In contrast, mechanical fuel pumps are simple design and far less expensive but are not practically fail-safe under all conditions. They prove lesser in efficiency with greater engine speeds and become susceptible to vapor lock especially during hot weather. Besides, they deliver fuel at relatively low pressure only.
Electric Fuel Pumps
Modern fuel-injected vehicles are predominantly fitted with electric fuel pumps. They have advantages over mechanical pumps in terms of performance, with higher pressure delivery, better efficiency, and more flexibility in their placement.
Electric fuel pumps tend to be placed inside the fuel tank so that they can work under the cooling effect of fuel, being completely submerged in it, thereby reducing the chances of vapor lock. It could be a turbine or gerotor rotary pump, driven by an electric motor.
Working Principle of Electric Fuel Pumps
Electric fuel pumps follow the same operating principle whether the design comes with variation or not. The engine control unit (ECU) takes an ignition signal to operate the fuel pump relay for pump activation.
The electric pump retrieves liquid fuel from the storage tank before transferring it along the fuel lines to the fuel rail. An electric Fuel Pressure Regulator functions to preserve proper fuel pressure in the rail while returning surplus fuel into the fuel tank through the return line.
Through this feedback loop design the engine always receives a steady fuel supply at proper pressure levels irrespective of speed variations or changing loads.
Drawbacks of electric fuel pump are electrical malfunction and high battery consumption, while the flaws of mechanical unit are component wear, noise, and periodic maintenance. So, while choosing consider your needs and car compatibility.
