Understanding and Function of the Feed Pump in Diesel Engines

Every diesel engine has an injection system to deliver optimal power. This system consists of a series of complex components connected to the fuel.  

In this case, feed pump is one of the important components for delivering that injection system. Let's take a look at the definition of feed pump and its functions here.

What is a Feed Pump?

Feed pump is commonly referred to as a supply pump or fuel supply pump. This component plays an important role in forming the diesel fuel system. 

Feed pump itself has two types of pump models that must be adjusted to the injection pump conditions in the diesel engine. Nevertheless, this device has the same working system.

Every diesel engine uses diesel fuel that must be delivered to the injector. Then, the injector system of this engine will inject it for combustion. 

However, the engine condition at high speeds sometimes requires the assistance of a feed pump to process this fuel. 

Functions and Working System of the Feed Pump

Before understanding the function of this tool, you need to understand the working system of the feed pump. In this case, feed pump has various other constructions that help this tool to work well.

There are camshaft, tappet roller, piston, push rod, inlet valve, piston spring, pressure chamber, outlet valve, and space under the piston.

Then, the feed pump placed on the side of the fuel injection pump will be driven by the camshaft. The movement of the feed pump by this component will also create a back-and-forth movement of the piston. 

In this case, the piston that works by sucking and pressing the fuel is part of the function of feed pump.

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To understand this working system, you should know in detail about the suction and pressure steps of the fuel in detail. 

When sucking, the camshaft construction does not press the tappet roller. However, this condition will direct the piston to press the push rod due to the tension of the spring generated.

Typically, this condition will cause the pressure chamber to increase its volume. This enlargement can also affect the construction of the inlet valve to open. As a result, the fuel in the tank will be sucked in and enter the pressure chamber. This condition does not even affect the outlet valve, so it remains closed.

Feed pump also has the function of pressing the fuel through its construction. In this case, the camshaft will rotate to press the tappet roller. 

Then, the tappet roller will push the push rod which can cause the piston to move upward. This certainly has a working system that is the reverse of the suction step so that the volume of the pressure chamber becomes smaller.

This reduction in volume can even result in an increase in fuel pressure. As a result, the outlet valve opens and closes the construction of the inlet valve. 

Certainly, the function of feed pump in this condition can cause the fuel in the pressure chamber to exit and go to the injection pump through the fuel filter.

In this case, fuel pressure that is too strong and reaches 1.8-22 kg.cm3 can cause idling or a condition where the fuel cannot be sucked or pumped. 

The condition of the push rod that continues to rotate to pump this does not even succeed. The fuel pressure that is too strong causes the spring force of the piston to not be strong enough to counter this pressure.

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