How to Change Your Fuel Filter？
Diesel engine because of its low fuel consumption, low torque strength and other advantages, is widely used in commercial vehicles, but when it comes to the replacement of diesel filter, I believe you will say “and replace the gasoline filter no difference”, so think is very wrong. For the replacement of diesel filter, it is more complicated, and today, based on this case, I will tell you about the replacement method of diesel filter.
一、Replace the fuel filter element
1, prepare a chain wrench, and replace the oil filter wrench can be the same.
2.Disconnect the lower sensor plug before disassembly.
3. Loosen the fuel filter clockwise and tighten it counterclockwise.
（The removal of the diesel filter is relatively simple, similar to the way that the oil filter is replaced. It should be noted that the moisture sensor at the bottom of the filter element should be avoided during disassembly.）
（When replacing the filter element, we need to remove the water content sensor, which does not need to be replaced）
二、Why do fuel filters have sensors？
1. Why add various sensors？
Due to the working principle of compression combustion, diesel engines have high requirements for fuel concentration and temperature. Therefore, it is very critical to detect the status of diesel oil. Subject to the influence of air temperature, humidity, etc., the water content of diesel will also increase with the increase of use time, which is not good for engine combustion, so the design of these sensors can monitor the water content and temperature in the filter in real time, so that the engine can be better corrected.
2. Why does diesel oil contain water？
The volatility of diesel is poor, due to the composition of the fuel, and the ability to absorb water molecules in the air is also stronger. With the increase of use time, the water content in diesel is also greater, thus reducing the engine combustion efficiency, and it will ice block the oil pipe in the low temperature state. Therefore, after removing the old filter element, we should not only check the color and impurities of the diesel, but also check the amount of internal water content.
（After removing the filter element, be sure to pour out the internal diesel, check the magazine and color in the oil to check whether there is serious damage）
What do I need to pay attention to when replacing the filter element?
1.Replacement of sealing ring
Diesel belongs to compression combustion, so the pump oil pressure of diesel is very large, which is 2-3 times higher than the pressure of gasoline vehicles, which has a great impact on the filter seal ring. Therefore, when replacing the filter element, we must replace the new sealing ring, and we must not use the old sealing ring instead.
2.Pour diesel fuel into the new filter element
After the removal of the filter element, the residual diesel in the pipeline will flow out, so that the pipeline into a lot of air, if you do not pour new diesel, it is very difficult to start, this principle is very similar to our artificial well killing. New diesel is needed as an “introduction”.
3.Installation of water content sensor
After all, it is a sensor, and we need to understand the status of the line plug to avoid corrosion and rust. The combination should be tight. When your water content is too large, the instrument light will alarm, at this time you should remove the sensor, the water accumulated in the filter element out. We can also see the regular maintenance of 3000 kilometers of emissions once.
（The installation of the water content sensor we must ensure that the plug has no obvious corrosion and water intake. The sensor should be properly placed after disassembly to avoid external damage to the detection head.)
4.Press the diesel hand pump in the engine room before starting
Most diesel vehicles use mechanical oil pumps rather than electric fuel pumps. The essential difference between the two is that the mechanical oil pump is installed on the engine, and the electric oil pump is soaked in oil. This also leads to the replacement of the filter element, we must use the hand oil pump to first extract the diesel in the tank to build pressure for the pipeline, otherwise a large amount of air stored in the pipeline will not be able to start.
During the first startup, it is normal to encounter startup difficulties. We can eliminate this problem by rebooting. Under normal circumstances, if the pressure of our hand oil pump is normal, the start is very smooth.
In principle, the diesel filter element and the gasoline filter element are the same, which are the role of filtration. However, in the replacement of the filter element, it is far from the same. Pay attention to every detail, in order to replace the diesel filter in good condition, it can be said that the above steps are indispensable. For you who have raised a diesel car, have you learned to replace the diesel filter element now?