Modern diesel engines - complex and accurate mechanical systems, to break the work of which are capable of the smallest extraneous particles. Guarding the well-being of the motor facilities are filters of cleaning diesel fuel. Externally, they are fundamentally different from the "brothers" gasoline.
The device and the principle of operation of filters of cleaning diesel fuel
Before diesel fuel will be used for its intended purpose, it is purified by contamination and water. This is necessary, since in the nozzles and cylinders fuel comes under great pressure. Foreneous dust in this case turns into abrasive, quickly deriving the part. Dirty fuel is the main reason for premature failures of diesel engines. In their power systems, two fuel cells are usually installed: rough and thin cleaning. Solutions with one or three steps of filtration are less common. The separation of functions between fine and coarse cleaning filters is not dogma. For example, removal of water from fuel can be assigned both to the first and second or both at once. It all depends on the design solution.
Dirty fuel - the main reason for premature failures of the pump, nozzles, pistons and cylinders of diesel engines
Filter of coarse fuel purification (FGOT) holds large extraneous particles with a diameter of about 100-300 microns. Smaller fractions stop the fountal filter (ftot). The size of the captured dust depends on the requirements for fuel engine. So, the engines of the progressive system itself COMMON RAIL.whose nozzles work under pressure up to 2.5 thousand atmospheres, it is necessary for the cleanest fuel. Permissible size extraneous particles for them are not larger than 3-5 microns. Conventional diesel motors with plunger fuel pumps High pressure (TNVD) less "capricious", since the operational fuel pressure in them is significantly lower. Place FGOT in the system - to a pre-pump feeding fuel to the supercharger (high pressure fuel pump). FTOT is placed before the pump.
The filter of coarse cleaning of diesel fuel is installed to a preliminary pump, thin - in front of the fuel equipment
Device of coarse filters of diesel fuel
A common design of FGOT is a collapsible glass with a replaceable filtering element.
Complete design FGOT- collapsible glass with replaceable filtering element
In the filter-sump, the cleaning element is made in the form of a grid. Inside the glass, additional elements can be placed, which improve the functioning: reflector, soothing, etc.
In the filter-sump, the filter element is made in the form of a mesh
Some cars use unsubstantiated universal direct-flow FGOTs in a transparent plastic case, externally similar to gasoline. For example, the WK 31/5 filter is installed in Mercedes-Benz W124.
River filter of rough cleaning of diesel fuel similar to gasoline
Experiments on the installation of a diesel engine on a serial passenger car in Europe began in the thirties of the twentieth century. For example, in 1936, there was a 45-strong version of Mercedes 260d with the brainchild of Rudolph Diesel under the hood.
Diesel fuel filtering device
They are fundamentally characterized by the properties of filtering elements and the size of the dust held.Filtering element - the main detail of the FToth. In addition to it, the filter can be equipped with a separator for separating moisture from fuel, a crane for draining the accumulated water and the sensor of its presence.
In addition to the fette filter element, it can be equipped with a separator for separating moisture from fuel, a crane for draining the accumulated water and the sensor of its availability
Structurally, these elements are performed both in unimprovable and collapsible. In the second case, either a cartridge or a cartridge is used as a replaceable element. The cartridge is an adversary replaceable element from filter paper or other small-handed material - installed in the body of plastic, aluminum or steel. The fetoth cartridge is the same cartridge, but placed inside the eigen body. Some fuel cartridges can be used for oil cleaning. The fuel filter form two elements: cartridge and lid.
Photo Gallery: Filter Designs
Inside fine cleaning filter assembled in a closed case 
If necessary, replace only the folder cartridge 
Inside the collapsible filter is a replaceable cartridge 
The cartridge filter consists of a lid and cartridge 
Replaceable cartridge element - the same cartridge collected in a separate case
Video: Filter Device
Choice
Correct selection strategy fuel filter - Perform the recommendations of the car manufacturers. They are designed taking into account the needs of the engine. Do not experiment, installing an inappropriate filter only for the reason that he is cheap.
Some motorists are trying to compensate for the low quality cleaning of the frequent replacement of the fuel cell. This is the wrong approach. The main task of the filter is to prevent fuel equipment and cylinders of foreign particles are larger than a certain size. Filtration subtlety is one of the characteristics that does not change during operation. Neither old nor new elementwhich is not able to keep small particles, does not save the engine from breakdown.
Filtration subtlety - one of the characteristics of the filter that does not change during operation
Similar filters are released different companies. Famous brands MANN, Knecht (MAHLE), Bosch, UFI, Delphi and others occupy a leading position in the market, as they produce high-quality products that car manufacturers are installed on new machines. Use online directories to select a suitable filter. Choose only those models in the description of which there is a direct recommendation for your car.
Photo Gallery: Fuel Cleaning Filters Famous Brands
Bosch filters - one of the cheapest among famous brands 
Mann offers the widest range of various appointment filters 
Delphi is one of the few companies that have mastered the production of filters for diesel engines COMMON RAIL. 
Knecht-Mahle - Luxury German Brand 
Italian UFI company supplies filters to the Volkswagen assembly conveyor
Video: Overview of fuel filters
Replacement regulations
Signs of the need to replace fuel purification filters:
- difficulties with engine stop,
- spontaneous motor stop,
- low power
- noisy engine operation,
- abundant black smoke from the exhaust pipe.
Wait until the listed symptoms are dangerous. The diesel engine does not tolerate the inattentive relationship. Sendance with the replacement of fuel filters reduces the resource of the motor and provokes a premature failure. To avoid trouble, change the filters at least than recommends a car operating manual.
The Belgian importer of the Volga in 1960 began to install several types of atmospheric diesel engines on the "twenty-first" varieties of atmospheric diesel engines. True, the car "stopped going", but in Western Europe, the savings were much more important than the dynamics.
Manufacturers constantly improve diesel engines fuel filters. The estimated resource of modern replaceable filter elements reaches 90 thousand km of mileage. Practical recommendations Car manufacturers are much more modest, which is explained by two factors. First, the life of the fuel is very strongly affected by the service life. There are no clogging indicators in the filters, so it is impossible to check the status of filtering elements without disassembly, and it is better to be restrained than to apply a significant damage. Secondly, the corporate service brings significant profits from which brand owners are in no hurry to refuse.
Uniform recommendations for replacing filters for all diesel cars does not exist. Usually they make up 25-40 thousand km of mileage. The root cleaner, if there is, and in the car's guide there are no special recommendations, change together with the main element of fine cleaning.
The figures provided are only generalized data that is not intended for practical use. Take a look at the "keywater" of your car. It is possible that its manufacturer considers it expedient to change the filters more often. For example, for diesel cars Renault Duster. In 2015, the filter resource was installed 20 thousand km of mileage, before this date it was only 10 thousand km.
Low-quality fuel significantly reduces the service life of the filter. To harm the engine, sometimes just one refueling. Noticing something wrong after visiting the gas station, drain the suspicious fuel and fill the tank obviously qualitatively. As soon as possible replace the fuel filter, even if the signs are not stable work disappeared.
Heated engine cleaning filter on diesel fuel
Feature winter operating Diesel fuel is the crystallization of paraffin in it. Due to the low temperature, paraffins fall into the sediment, scoring the fuel filter and fueling. Winter fuel is resistant to a greater extent than summer, but it can be frozen.
Due to the low temperature, paraffins fall into the sediment, scoring the fuel filter and fueling
The correct method of combating paraffin crystallization is heating the fuel cell. In some cars, it is implemented constructively, for example, in Renault Duster.
In some cars, heating is implemented constructively, for example in Renault Duster
You can equip a heated car by installing a heated filter instead of a regular or in addition to it.
It is possible to equip a heated car by installing a heated filter instead of a regular or in addition to it
Alone and with minimal cost, the problem is solved by installing the electrical band heater on the existing filter.
With minimal cost, the problem of heating solve the installation on the existing filter of the electric band heater
Video: Fuel filter heater do it yourself
Reliable fuel filter - prerequisite long operation diesel engine. Save on the filter is impossible. Motor repair will cost more.
Performs one of the most important functions in the car device. Accordingly, many motorists are interested in the question - how to choose the right filter element and which is better to install on your car. We will pay attention to this issue today. What is it better to purchase a fuel filter for a diesel engine, read below.
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Fuel filter functions
Before we proceed to choosing a filter, let's still find out which functions it performs. So, as you understand, the fuel filter for the diesel engine is designed to clean the fuel.
In general, the cleaning process is carried out in several stages:
- pre-cleaning procedure, which is carried out in fuel tank;
- the next stage is a rough fuel purification;
- the final stage is fine cleaning.
It's no secret that diesel system Nutrition is the most demanding in the matter of fuel purity. Diesel engines precision pairs are installed not only in the nozzle, but also in the fuel pump itself. Accordingly, the excessive presence of impurities in the fuel can be negatively affected not only on the operation of the nozzles, but also the pump. This means that fuel filtering should be carried out in several stages.
White paraffin - appears on the filter usually during operation in cold weather The principal difference in fuel filters for diesel engines is that they effectively prevent moisture from entering the motor combustion chamber. In addition, some models of fuel filters (hereinafter referred to as TF) for diesel engines are equipped with heating elements. This is done in order to be in the frost of paraffin, which are contained in the combustion, did not fail the system as a result of crystallization.
As is known, fuel pollution for the most part occurs during its production in the enterprise. The rest of the substances harmful to fuel fall into it during transportation and, accordingly, refueling. It should also be noted that in a combustion, various chemical processes occur regularly, which contribute to the appearance of all sorts of resins. Moreover, a condensate begins to appear in the temperature differences in the gas tank, and it, in turn, interferes with the fuel during the ride. Accordingly, the initial TF function for a diesel engine is to clean the fuel from dirt, impurities and moisture.
Diesel engine fuel filter device and service life
In general, diesel engines are very sensitive to the garbage and moisture that are present in the fuel. Moreover, the quality diesel in domestic gas stations is not so easy to find. This sensitivity is caused by the content in the nozzles and the fuel pump of precision elements that are lubricated with diesel. In some nodes, the gap between the details is not more than 6 microns, respectively, the presence of abrasive materials may cause an increase in this gap. As a result, the system can and easily fail.
As practice shows, almost half of diesel malfunctions are caused by breakdowns in fuel system. This means that from how TF is cleaning the fuel, the engine performance as a whole and its resource works directly. We now turn to the issue of the fuel filter device for a diesel engine. In general, the device of the element is quite simple. TF consists directly from the filtering component itself, as well as separators that are necessary for separating water from a diesel engine, and in some cases - moisture sensor with a crane for its drain.
According to the photo below, consider the TF device:
- Diesel requiring filtering.
- Emulsion after the pump.
- Department of elements and formation of condensate drops.
- Already cleared diesel drives with condensate droplets.
- Hydrophobic element.
- Condensate sump.
In general, this device is characteristic of diesel TF. In order to in the tank vehicle No moisture appeared, some manufacturers advise to refuel the tank completely at least once a week. As for the resource of operation, it directly depends on the quality of the feeding diesel fuel, on average, this indicator is about 30-40 thousand mileage kilometers. The inability of the fuel filter for a diesel engine to perform its functions lies in power loss when driving uphill. If you do not change TF in time, then the problem will be developed further, until the moment that the motor simply fails to be launched.
How to choose the right one?
So, if everything is clear with the functions and the device, then consider the following question. What is better to choose a fuel filter for diesel engine?
To do this, take into account several aspects:
- Buy only original TF for diesel units. To date, the choice of filtering elements for diesel vehicles is simply huge. Therefore, when buying it is important not to get caught in counterfeit products. Most optimal option It will be the acquisition of the original TF, which is intended directly for your car. In this regard, when buying it is important to pay attention to the serial number, it is desirable that it corresponds to the one that indicated the manufacturer.
- Before purchasing, you need to determine the necessary filtering subtlety. When you buy TF, pay attention to its description, it must be marked several parameters, in particular the nominal and absolute level of filtering. This indicator is measured in microns (microns). The nominal indicator determines the particle size that is delayed by a filtering element by 95%. The absolute filtering indicator as a whole determines the quality of cleaning and class class, it is 98%.
It should also be noted that each other filters differ on the elements of thin and coarse cleaning. The TF of coarse cleaning is designed for the preliminary process of cleaning and eliminate the largest particles of the grasp of fuel. The TF thin cleaning is necessary for cleaning the fuel, which has already passed through a coarse filter. To date, the principle of double cleaning is the most common and effective, because it allows you to ensure reliable protection of the system. In addition, when double cleaning, the resource of both TF is significantly increased. - Remember that always low-quality TF are the cheapest. It is no secret that the high-quality filter component is much more expensive, because it is it that determines the price of the part in principle. To date, synthetic, pulp and combined materials can be used in TF. Fully synthetic elements are the most expensive price in terms of price, while they have the longest service life.
Cellulose TF are considered inexpensive. And no wonder, because their design for cleaning is equipped with a special porous paper with the impregnation function. As for the combined elements, they, as a rule, alternate synthetic and cellulose layers, which makes it possible to filter the dirt from fuel at a decent level. - For diesel, it is also necessary to additionally install the water-fuel separator. The purpose of the separator is to the condensate separation from fuel, as well as in preventing it in combustion. It is no secret that moisture significantly reduces the productivity of the unit as a whole, and in the event of its freezing during frosts, this may be damaged to the elements of the entire system. Often separators are mounted in a compartment with basic TF.
- And the last - TF should be installed together with the heating device. When the temperature ambient Falls, fuel "seaspled", respectively, its feeding to the motor will be difficult. In order to prevent this, it is desirable in addition to the main TF, to establish a heating device. Thus, even in a strong frost, TF will always be heated.
Video "Heated Diesel Filter"
The performance of the TF heating system is presented on video.
The diesel engine fuel apparatus is very sensitive to pollution. All work on cleaning take on fuel filters for diesel engines. Up to the hit directly in the combustion chambers, 3 stages of purification: pre-filtration in the fuel tank, steps "coarse" and "fine" cleaning.
Problems that solve diesel fuel filters
The main task of such filters is to prevent the penetration of abrasive impurities and the resin generated due to chemical reactions, Fuel line and combustion chambers. Due to the large moisture content in the dieselopliva, unlike gasoline, diesel fuel filters should condense water and delete it from the fuel supply equipment in a large amount.
However in diesel fuel There is a high content of paraffins, which crystallized at negative temperatures. Eating such particles into the engine often becomes dangerous for him. Best way Combating this problem is the use of heated filters.
In the event that the fuel filter for the diesel engine is already parefin, it is necessary to replace it.
Stages of cleaning diesel fuel and types of filters
The first obstacle on the weighing path in the combustion is the filter element in the fuel tank of the car. As a rule, it is a frame that is walked into the grid, which is a barrier for solid particles. This type of cleaning cannot prevent small particles, water, paraffins and resins into the fuel equipment.
But thanks to him, most of the major elements are sifted - corrosion and garbage products. They are present in any fuel tank. This prevents the clogging of highways low pressureand also significantly increases the service life of a coarse cleaning filter.
In most cases, the replacement of this element is not regulated by the manufacturer, but it is recommended to do it. Its service life directly depends on the novelty of the car, its technical status and fuel quality. The net element in the car's tank is the cheapest link in the entire fuel supply chain into the engine, but no less important, so you should not neglect it with check and, if necessary, replacing.
For the second stage, filters are answered by the "coarse" fuel purification (filters-sumps). Their name is determined by the presence of a glass-sump. At the bottom of it is equipped with a sedative, thanks to which it is possible to remove water.
And in its upper part there is a mesh or plate filtering element, which allows to get rid of particles with a size of up to 0.05 mm remaining after the first stage. Next, the fuel enters the low pressure fuel pump (TNND).
This type of filter has a drain plug for cleaning a glass of condensate and sludge. Most septic filters have a collapsible design. Such a diesel engine fuel filter device provides the ability to rinse and, if necessary, replace the filter element and thereby restore the cleaning efficiency.
A special type of filters at this stage are heated separators for diesel fuel. Their price is significantly higher than that of conventional filters-sumps, but the quality of cleaning fuel is more efficient, and heating solves the problem of paraffins. They are able to remove up to 95% water and impurities from diesel fuel.
The cleaning process begins with a phase of fuel heating, which prevents the crystallization of paraffins and water. Next, under the action of centrifugal forces arising from the twisting of the emulsion passing through special channels, water and impurities are separated and settled in a glass-sump.
For the separation of smaller particles, the principle of changes in the flow direction, which is implemented using the separator blades. The final stage is a corrugated cartridge that removes the smallest solid particles.
Filters "Rough" cleaning, connected to the pumping pump or a "fine" cleaning filter.
In most cases, pollution of filters "Rough" cleaning will not be felt during the operation of motor vehicles, because The performance of TNND is always higher than necessary for stable engine operation. Therefore, in order to prevent expensive repairs, it is necessary to reduce the accumulated water and garbage from the sump and not ignore the need to replace the filter element.
The final obstacle to fuel before its receipt in the diesel engine serves as a "fine" filter. It allows you to get rid of solid particles remaining at the previous stages, which are not visible to the eye, as well as the resulting resins. Another feature is the protection of the engine from the air that has fallen into the fuel in the early stages of cleaning.
Through the fuel oil valve, the fuel surplus is returned to the tank. The difference in the temperatures of the distinguished mixture and fuel in the tank contributes to the formation of condensate and an increase in water content. The function "fine" cleaning at this stage performs a replaceable element consisting of special porous paper.
Often, the replacement of only this element is regulated by the manufacturer. Because of this, a frequent error becomes ignoring the need to maintain the remaining filter elements.
Selecting the fuel filter
Before choosing any fuel filter for diesel engines should be considered constructive features Your car. In no case cannot be used gasoline fuel filter! He will not be able to prevent water and paraffin in the engine.
Most modern diesels passenger cars Foreign production is equipped only with a "thin" cleaning filter. In this case, it is impossible to be limited only to the compliance of the regulations. It is necessary to equip the car with an additional fuel purification link. An ideal option will be the installation of a heated filter-separator.
Here are the main characteristics to pay attention to when it is selected: bandwidth, power of the heating element, filtering quality, allowable pressure and dimensions of the product. For normal operation of the vehicle, all these parameters must correspond to the characteristics of the engine power system.
Thus, the bandwidth for engines with high-pressure fuel pumps (TNVD) is in the range of 20 to 50 l / h (in rare cases up to 60 l / h). And with COMMON Rail systems and pumps-nozzles - from 40 to 80 l / h.
The same applies to the quality of filtration for engines with an edge, sufficient value, will be 10-30 microns, and for Common Rail, this parameter should not be worse than 2-5 microns. To create a centrifugal effect and high-quality filtering for vehicles with a small fuel consumption, you should choose a small volume filters, and when big flow - On the contrary.
Deciding with the type of filters, it is worth paying attention to their quality. Currently, the market is filled with all sorts of proposals. With the stated similar characteristics, the price may differ 10 times. But you should not succumb to the temptation of this cheapness.
Most. the best option It will use the original components, but if there is no such possibility, it is worth paying attention to the proven brands: Mann, Knecht, OE, Bosch, etc. Often such large companies are suppliers of original components. The higher the cost of the filter, the better the degree of filtering.
Replacing the fuel filter
This procedure requires certain skills and experience. Item replacement technology is different from different models cars. It is important to familiarize yourself with it before any work. Strict compliance with replacement technology guarantees you good job Engine in the future.
With due skill, this procedure can be performed independently. To do this, it is necessary to remove the filter element, remove the garbage and water from the case and get rid of air in the power system. If you do not know how to perform these actions, refer to the service.
