How to Tell if the Diesel Fuel Injection Pump Is Bad and How to Remove It?

Diesel engines are an essential source of power for heavy machinery such as loaders, tractors, and excavators. High-pressure fuel injection into the combustion chamber is the function of the diesel fuel injection pump, a crucial component of a diesel engine. However, fuel injection pumps may malfunction with increased use, which would impact engine performance. You will get a thorough explanation of the diesel fuel injection pump's operation, how to identify damage, and how to remove it in this article from MyMROmarts.

 

How Does a Diesel Fuel Injection Pump Work?

The main function of a diesel fuel injection pump is to transport diesel fuel from the fuel tank to the combustion chamber and inject it precisely at high pressure. This acts so that the diesel fuel can be completely burned to provide power for the engine. The working principle of the injection pump can be divided into the following steps:

1. Suction process

Fuel from the fuel tank through the fuel pipeline into the fuel injection pump inlet.

2. Pressurization process

The fuel injection pump pressurizes the fuel through the internal high-pressure components. This process enables the fuel to overcome the fuel system's resistance and is injected into the engine combustion chamber under high pressure.

3. Fuel injection process

The pressurized fuel is precisely injected into the combustion chamber. At this point, the fuel has become atomized and is fully mixed with the air. The fuel in this state can achieve the best combustion effect.

4. Control of injection volume

The regulation system in the injection pump can control the fuel injection volume according to the engine load and speed. This makes the engine work properly under different working conditions.

The injection pump is usually connected to the engine crankshaft or has an electronic control system control. Its precision and stability directly affect the engine power output and fuel efficiency.

 

How to Tell if a Fuel Injection Pump Is Bad?

If your heavy-duty equipment is experiencing problems such as hard starting, lack of power, and increased fuel consumption, the fuel injection pump may be at fault. Here are some common symptoms of diesel injection pump failure that you can test yourself.

1. Difficulty or inability to start the engine

If the fuel injection pump is damaged, it will make the fuel supply insufficient or uneven injection.

2. Decrease in engine power

If the injection pump is unable to inject fuel as required, it will also lead to incomplete fuel combustion.

3. Increased fuel consumption

A damaged fuel injection pump can lead to inaccurate or excessive fuel injection. This results in abnormal fuel consumption.

4. Black smoke or abnormal emissions

Incomplete fuel combustion occurs when there is a problem with the injection pump. Heavy equipment such as excavators and tractors will emit black smoke.

5. Engine shaking

Uneven fuel injection will make the engine run unevenly.

 

How to Remove Fuel Injection Pump?

If you judge that the diesel fuel injection pump has been damaged or needs to be repaired, removing the injection pump is a necessary step.

1. Preparation

Before removing the pump, ensure you have prepared the necessary tools and equipment, including spanners, screwdrivers, fuel line removal tools, etc. Meanwhile, it is best to be in a clean working environment. This will also prevent impurities from entering the fuel injection pump system.

2. Cut off the power supply

Firstly, cut off the power supply of the heavy equipment to ensure safety during the disassembly process.

3. Drain the fuel

To avoid fuel leaks, it is recommended to drain excess fuel from the fuel system before disassembly. Loosen the connecting screws on the fuel line and drain the excess fuel.

4. Disassemble the fuel line

Loosen the fuel line connecting the injection pump, taking care to avoid fuel leakage during disassembly.

5. Remove the injection pump fixing screws

The diesel injection pump is usually fixed to the engine by a few screws. Depending on the model, use the appropriate tools to loosen these screws. Afterward, remove the injection pump from the engine.

6. Disassemble the pump body

After removing the fuel lines and fixing the screws, you can gently remove the injection pump. Pay attention to the orientation of the pump body during disassembly to ensure that it is correctly aligned when reinstalled.

7. Cleaning and inspection

The disassembled jet pump needs to be cleaned and inspected. Check the inside of the jet pump for damaged parts.