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How to Test Your Diesel Injection Pump?

by LiMona 25 Sep 2023



Injection pumps are one of the main components of any modern vehicle. Whether you own a passenger car, commercial or industrial vehicle, or a pick-up truck, you can't expect it to run without an injection pump. So, you need to know how to test a diesel injection pump to ensure it works flawlessly.

What does a diesel fuel injection pump do?

So, what does a diesel fuel injection pump do? It's about as simple as you can get: fuel injectors supply fuel to the engine's internal combustion chamber.

The fuel is dispersed from the injection pump to the combustion chamber via a relatively simple process. Pressurized fuel enters the fuel injector. Based on a signal from an electrically controlled solenoid valve – the solenoid valve acts as an on / off valve – the fuel enters a plunger, preparing the fuel for the final exit. When the fuel leaves the fuel injector, a spray tip distributes the fuel as a fine mist.


How to Test a Diesel Injection Pump?


When checking diesel pump performance, there are several ways you can go about it. While you may find professional services for a fair price, you can also do the testing yourself. But before you begin the process, you must know that it can be hazardous if you don't have prior experience.

You'll work in a high-pressure environment when dealing with a fuel injection pump. Since the pump develops incredible pressure at about 15,000 psi, the fuel will leave the injector at approximately 3,000 psi. 

Therefore, the pumped fuel can easily cut through your clothing and skin if you come in the way. This can cause severe medical conditions, leading to amputation and even death.

Now that you know the risks of this process, we recommend that you always apply the needed safety measures if you plan to calibrate yourself. If uncomfortable with your experience, always turn to a professional service. This doesn't only ensure your safety but also the best results.


Take safety measures

The first step in checking diesel pump performance is to take the necessary safety measures. Besides the potential injury risks, you must also watch out for fire hazards. Remember that fuel is a highly flammable material that shouldn't be taken lightly. Thus, we recommend that you have the essential fire safety equipment.


Check fuel pressure

The next step in the diesel injection pump testing is to check the fuel pressure. To successfully do this, you'll need three main pieces of equipment. The first step is to disconnect the low-pressure fuel line quick connector. Then, you insert the connection adapter into it. Once the connection adapter is safely installed, you can connect the low-pressure gauge connection tube. Lastly, place the low-pressure fuel line on the other end of the box.

After doing so, insert the low-pressure gauge in its designated place on the tube and begin testing. For a static test, turn the car on and start the ignition. If you can't start the vehicle's engine, you can crank it for five seconds. Then, you can leave the car and check the readings on the low-pressure gauge. 

As for the dynamic test, you should start the engine again and then leave it idle. After a few seconds of idling, you can check the pressure changes on the gauge again. Once you've gotten the proper readings, you can move on to the next test.


Check fuel delivery

The second test you should do is check the fuel delivery. You'll need either a flow meter or a measuring container for this process. Since a flow meter is usually a piece of equipment found in repair facilities, it may take much work to get your hands on it. 

That's why most people go for measuring containers. The best material for this purpose is glass because the fuel can fog up anything made from plastic. 

The basic concept of a time fuel test is to see how much fuel you can get out in a specific timeframe. We recommend starting with a simple five-second time window to avoid fuel spillage. 


Compared to the manufacturer's specifications.

Once you've gathered the needed test results, you should always check the manufacturer's specifications. Remember that different car models have distinct readings and specific you should base your results on. 

You can define any problems that may have occurred with your vehicle only when you've compared the readings. 

Furthermore, depending on the numbers you get, you'll know if you have a clogged filter and line or a fuel pump problem. By finding the real problem, you can better calculate your expenses if you need to replace any failed parts.



If you're aware of fuel injection pump problems with your automobile or have questions about fuel pump replacement components, hpinjection has the answers you're looking for – and the products, too! 

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