Types of fuel filters for diesel. Laboratory quality fuel filters

System Common rail  in recent years has received the widest distribution in the world. If in 2008 the share of diesel engines equipped with such a fuel system on the market was 24%, today this figure already exceeds 70%. In the future, this figure will grow. Since the advent of Common Rail in the mid-90s, it has gone through several stages of development, as a result of which the pressure in the fuel system has almost doubled. All this had a strong impact on the market segment. fuel filters  for diesel engines.

Continuously variable transmissions

If we compare the segment of fuel filters for gasoline engines and diesel engines, we will see that they are developing fundamentally in different directions. In the segment of gasoline engines, many more manufacturers are represented, but by itself it becomes less and less attractive for participants every year (if we talk about the aftermarket). Most modern cars with petrol engines are equipped with fuel filters, which are installed for the entire life of the car.

"Roughly speaking, fuel filter  in a modern gasoline engine has ceased to be a consumable material, says andrey Aleksyuk, Head of the Marketing Department of the MANN + HUMMEL Company,  - it is installed on the fuel pickup and changes only in case of a breakdown. There is no regulation for replacing this filter, whatever some mechanics may say. The share of cars equipped with such filters is already quite high today and will continue to grow. ”

Growth is not for everyone

And what happens in the segment of diesel fuel systems? As already noted, the share of Common Rail has increased dramatically - fuel system, which is known to be extremely sensitive to the quality of fuel filtration. So the capacity of this market segment is growing, but only a few companies that have the technology for producing filters for Common Rail - Bosch, MANN + HUMMEL, Mahle, Delphi and several other less well-known brands on the Russian market will be able to use this growth. The likelihood of new players here is not very high. The production of fuel filters for Common Rail is the most complicated technological process. First fuel common systems Rail had a working pressure of about 1200 atmospheres. The systems of the current, fourth generation are already operating at a pressure of 2,500 atmospheres. Making a filter that would simply withstand such pressure is no longer the easiest task, but in Common Rail systems it must also hold up to 98% of particles no larger than 3 microns, remove liquid emulsions and moisture from the fuel to prevent internal corrosion. .

“At the same time, the amount of fuel that is pumped through the fuel filter in modern diesel engines is very large. In one hour of engine operation, dozens of liters of fuel are pumped through. Most of it is drained into the “return pipe”, but the filter must clean the entire volume of the pumped fuel, - says Andrey Aleksyuk.  - In other words, it should have a high dirt holding capacity, a fine level of filtration and a high throughput. As you understand, it is rather difficult to fulfill all these requirements, which is why the number of manufacturers who are able to produce reliable fuel filters for modern Common Rail systems is very small today and they are at the cutting edge of these technologies. ”

This is how it describes the work of a modern fuel filter for diesel engines. sergey Yenin, product manager for Bosch filters in Russia:

"Structurally fuel filters diesel fuel  are performed by quick-change. Bolt-mounted filters, feed-through filters and filter elements installed in aluminum, plastic or sheet steel housings are used as replacement elements (in accordance with the increased requirements to prevent severe consequences during collisions). Preference is given to spiral V-shaped filter elements. The separation of water is carried out by coalescence on the filter material (the formation of water droplets due to various surface tensions of water and fuel). Water accumulates in the chamber at the bottom of the filter housing and is manually drained through a drain plug or a solenoid valve controlled by a button. ”

At the top of the evolutionary chain

The further evolution of Common Rail systems is forcing filter manufacturers to also complicate their products. In addition, as we see in the composition of market participants, the key developers of fuel systems for diesel engines prefer to independently produce not only fuel equipmentbut also a filtration system. This approach is followed by Bosch and Delphi. Recent years have been very successful for this American company in the development of new types of fuel systems for diesel engines. One of the latest Delphi developments - the Delphi Multec ® Common Rail fuel system has been able to achieve a record low CO 2 emission and fuel consumption. It is used on many cars, including the newest Mercedes-Benz C-Class and Volkswagen Polo. Last year, Volkswagen even honored Delphi with the prestigious title Global Champion for developing a modern fuel system for a three-cylinder 1.2-liter Volkswagen engine that meets Euro 5 requirements. Also a great achievement was the creation of the world's first diesel-hybrid engine, which also runs on fuel Delphi system (first used in the industry on the Peugeot 3008 Hybrid4). All these developments require an integrated approach, which includes including the development of filtering systems for new systems. This is especially important in the latest generation Common Rail systems.

“In the most modern Common Rail systems, the fuel-air mixture is fed into the cylinders under a pressure of over 2500 atmospheres. This is ten times higher than in row-type diesel fuel systems. With such a high pressure, even very small particles of pollution that get into the combustion chamber, cause very great damage to rubbing parts, spray nozzles and so on. If earlier, in the presence of harmful impurities in diesel fuel, the fuel equipment first of all suffered, in modern engines with the Common Rail system this leads to damage to the cylinder walls. This very quickly leads to catastrophic consequences for the entire engine. ”notes Andrey Aleksyuk.

And the most harmful to the fuel injection system diesel engine  are the smallest particles, measuring approximately 3-5 microns.

"Only 5 grams of this material can lead fuel pump high pressure  diesel engine to complete wear, regardless of whether these 5 grams are in one or twelve thousand liters of diesel fuel ",  - adds Alisher Hudayberdiev, Regional Director Delphi Products & Service Solutions (DPSS) in Russia.

Owners of thousands of cars equipped with Common Rail systems have long been convinced that these statements are not at all "horror stories." Quite often, saving a few hundred rubles becomes the cause of repairs costing several thousand dollars. The most annoying in this situation is that if the owner had to replace the filter a little earlier, there would be no such problem.

“It is important to understand that the fuel filter for a diesel engine accumulates large volumes of dirt and moisture. Accordingly, in order to prevent them from entering the fuel system, it is only necessary to strictly follow the replacement regulations. Currently, typical replacement intervals for filter elements are up to 90,000 km, depending on the recommendations of the automaker. But in regions with poor fuel quality (Russia is among them), these intervals are much shorter, ”  - notes Sergey Enin.

Precautionary measures

It is worth adding that the Common Rail fuel system itself begins to unequivocally signal that the fuel filter needs to be replaced.

Here is a list of the main symptoms that indicate that the filter needs to be replaced:

1) The impossibility of killing the engine.

2) Power loss.

3) Excessive smoke.

4) Excessive noise.

5) Spontaneous damping of the engine.

If you find one of these signs, then the filter must be replaced, even if you drove on it significantly less than the prescribed period. Thereby you prolong the life of your diesel engine. After all, even one poor-quality refueling can lead to the fact that the fuel filter is completely clogged with dirt. Despite the fact that the quality of diesel fuel has noticeably improved in Russia in recent years, the likelihood of sticking diesel or water or mud at gas stations remains. Most often, commercial vehicles and special equipment, which operates not in large cities, but in quarries and remote areas, are at risk. Under these operating conditions, it is recommended to install additional fuel pre-filtration systems, as well as filter driers. Such pre-cleaning systems are widely represented on the market today. In particular, MANN + HUMMEL supplies the Preline system - a complete pre-cleaning line for diesel fuel from dirt. The company offers several models of such lines, which can be installed both on commercial vehicles and on passenger cars.

The development of high-quality filters for Common Rail is beyond the power of most aftermarket filter makers. This significantly limits the choice of filters, but, on the other hand, greatly simplifies it. If you are the owner of a modern diesel engine on which the latest generation Common Rail system is installed, then you will most likely have to choose between the original fuel filter and the filter of the company that supplies this product to the conveyor, and the differences between them will be only in packages. All other Common Rail fuel filter offers at great prices are risky. This is exactly the case when the game is not worth the candle.

Perfect work of any vehicle  depends not only on the conditions, but also on the quality of the fuel used. Surely every motorist has repeatedly encountered the fact that at some filling stations polluted fuel containing mechanical impurities, the smallest particles of water is sold.

To exclude possible contamination of the motor due to poor-quality fuel, fuel filters are applied coarse and fine cleaning. Such devices are capable of eliminating small particles of dirt, dust, rust, thereby providing a cleaner fuel to the engine.

Filtration stages and types of devices

It is important to note that the system that makes the fuel in the car more clean is divided into 2 steps:

• rough cleaning that removes all large particles of dirt;
• fine cleaning, which relieves fuel from small particles of dirt, dust.

Not all drivers know where the fuel fine filter is located, as well as the device for its coarse filtration. The removal of foreign particles can be carried out even before the fuel gets into the fuel system of the car, or the device can be located in the engine compartment under the bottom of the car. And the element of purification from small particles is located between the pump and the carburetor.

By structural properties of the filters are divided:

• Collapsible - mesh elements made of brass or ceramics in collapsible constructions, clean gasoline quite qualitatively. Among the advantages of such devices is the ability to disassemble them, wash them. After that you can reuse.
• Disposable - usually install such cleaners in front of the fuel pump. They have an inexpensive cost and at the expense of the spiral design serve longer, qualitatively carrying out the filtration of fuel.
• With a transparent case - they do an excellent job with filtration, they allow the driver to assess the degree of pollution, to change the element in a timely manner.

It is important to understand that the fuel systems of different cars may have their own characteristics. When selecting the parts is to take this into account.

Sometimes the fuel system may contain not two, but as many as four stages of purification.

All about coarse filters

Fuel filter rough cleaning  it is used not only to exclude coarse particles, but also to prevent water particles from entering the car’s system. It is able to trap particles larger than 0.1 mm. Especially important is the water retention for cars that run on diesel fuel, as it has a certain moisture content. Due to the fact that the water is heavier than diesel fuel, it, accumulating, accumulates at the bottom of the purifier.

Also in the diesel fuel is paraffin wax. It tends to crystallize at low temperatures. This can lead to a complete disruption of the entire fuel system. That is why filters for diesel engines are equipped with a heating element. Also, the device may have a special sensor that alerts the driver about the water level in the parts.

All about fine filters

For quality, clean fuel is needed. Even imperceptible to man mechanical inclusions are dangerous enough for the engine. The fine fuel filter allows you to trap impurities, the value of which does not exceed 60 microns.

A big mistake is made by drivers who do not use the fuel fine filter, but rely only on "grids" that are located on the carburetor and the neck of the tank. Even invisible tiny inclusions can cause serious damage to the motor.

For vehicles with a diesel engine, a fine filter for diesel fuel is also extremely necessary. If you ignore this fact and do not install a fuel fine filter for a diesel engine, the efficiency of the engine will significantly decrease and its breakdowns will become frequent.

The quality of gasoline rather demanding injection engine. The owners of such vehicles also install a filter sump, which is made of high-strength plastics and steel. It provides high-quality exclusion of unnecessary impurities, contributes to a long, uninterrupted operation of the injector.

It is worth noting that if the car, then the fuel cleaner must be cleaned or replaced in a timely manner. It is important to do this at least once per 25–30 thousand km of run. This will ensure reliable and trouble-free operation of the motor.

When do I need to change the filter element?

There are several indicators that should indicate to the driver that it is time to change the fuel filtering device:

• engine power has become lower;
• while reducing the speed of the machine often stalls;
• it's hard to go to the mountain;
• the car periodically twitches and troit;
• the engine does not start at all.

Summarizing all the above, it can be noted that for the operation of any type of vehicle engine it is important to have clean fuel quality. Even at proven gas stations, it is difficult to guarantee this level of fuel production. The only way out is to install devices that make it possible to clean the fuel, provide double filtration of the fuel from harmful impurities, particles of dust, debris and water. Selecting such a detail, it is important to consider the brand of the car, the type of engine, the type of fuel used.

Best prices and conditions for the purchase of new cars

Fuel filter  - One of the inconspicuous consumables in the car, which ensures proper and, most importantly, long engine operation. Its purpose is to remove solid particles, water, as well as dust, paraffins, and in general everything that a fuel mixture can bring with it from the fuel of a car (gasoline, gas, diesel).

High quality filter ensures long and proper operation of the engine. We will immediately conclude: without saving on the fuel filter, you reduce the possible cost of repairing the engine.

The principle of operation and possible malfunctions

The fuel filter is conveniently located between the fuel tank and the engine, and in older cars it is located directly in front of the carburetor. Filters for diesel cars are equipped with a membrane that promotes the separation of water from the incoming diesel. Motorists should remember that the old fuel filter cannot be cleaned on its own, so you have to buy a new one.

The “clogged” filter indicates the following:

1. The dynamics and power of the car decreased;
2. Fuel consumption increased;
3. Uneven work of the motor.

The following situation describes the malfunction of the filter: you want to make a maneuver at high speeds, such as overtaking, but the engine speed does not increase when you press the gas pedal. Another option: you simply stalled at the traffic lights.

The design of the simplest filter includes a housing with a filter element installed. The fuel, moving through the inlet pipe, gets inside the case, the particles in it are filtered out, after which it moves through the outlet pipe. The filter element itself is either star-shaped or spiral-wound (filtering is more qualitative in this case).

The most advanced filters inside contain special cellular material. Moving deep into the filter, the fuel is cleaned gradually - first large particles are separated from it, then smaller ones.

About filter importance

The injector injection nozzles react sharply to the purity of the fuel. They quickly deposited dust, dirt, waxes, sulfur, and more. Due to the lack of the right amount of fuel, there is a loss of power, or even a failure of a separate nozzle.

The fuel filter is especially important for car owners in Ukraine, Russia, Kazakhstan and Belarus. The fact is that our fuel is inferior to European in quality. In gasoline and diesel, experts notice the impurities still in the laboratory, and motorists are aware of their presence already on the road. Try to study your fuel filter and estimate how much dirt would appear on the injectors, pistons and engine walls in the absence of this filter. You can see:

• Mud. This indicates a high percentage of asphaltenes and resins in the fuel;
• Black dust. Speaks about the presence of manganese additives;
• Wave-like curvature. There is a large amount of water in the fuel;
• Black mucus. In the fuel was a fungus, bacteria.

We summarize: the fuel filter is vital, do not save on its purchase.

Deal with replacement times

This helps the manufacturer. Examine the documents on the car, or contact a specialist at the station. The latter option is preferable if you are accustomed to refuel at various gas stations and are not sure about the quality of the fuel. In general, European cars need to replace the fuel filter on average every 20,000 kilometers, if the engine is petrol, and every 50,000 kilometers, if it is diesel. In the expanses of the aforementioned countries, this distance may be twice as short.

Another option is to carry out the replacement ahead of time. It is enough to remove the filter and see how corrugated the corrugation is and how much black it has collected. Again, the quality of gasoline at domestic gas stations leaves much to be desired, so it is advisable to periodically check your filter and reinsure while conducting an early replacement. Believe, your car will only get better.

What types of fuel filters are found

The classification is simple and straightforward. It has the following structure:

• Carburetor. Very simple filters designed for use in high pressure systems. Do not pass particles up to 15 microns in size;
• Injection. Designed for a wide range of pressures. They are hidden in a very durable casing and provide fine cleaning of the incoming fuel. Debris trapped up to 10 microns;
• Diesel. Complicated filters that can trap both fine particles and paraffin, water. Modern filters detain all particles whose size is not less than 5 microns;
• Gas  (for cars with HBO). Purify the gas from impurities.

Filters for diesel cars

About fuel filters for diesel is worth talking separately. The fact is that such a fuel system is very sensitive to impurities in the fuel, and in particular to water. Water in poor-quality filters passes further into the injection system, disrupting the combustion process and contributing to corrosion.

Filters for diesel fuel are required to maintain their properties at temperatures below 0C. Paraffin crystallizes in a diesel engine, clogging the usual filter. Often found in the sale of special filters to control the temperature of the incoming fuel. If such control is not provided for them, in the cold, viscous diesel fuel with paraffin crystals will pass through them, which is why the filter is clogged. The engine in this case loses power, may stall.

About the complexity of the choice

As is the case with many other parts, check with the “primer”, which extends to your car. The characteristics of the filter to be bought should coincide with those stated by the manufacturer. Namely, such: linear dimensions, fineness of screening, type of engine and its volume.

Dropout dropout  - the amount of litter, the size of which is determined by the manufacturer of the filter, delayed by the filter itself. It is customary to denote a percentage. There are the following levels: medium, nominal, absolute.

• Average dropout  - the filter will hold 50% of particles having a certain size;
• Nominal  - similarly, but 95% of particles are retained;
• Absolute  - 100% of particles are eliminated.

So, let's try to decipher what the manufacturer of the fuel filter writes. It is written: "The nominal fineness of screening is 10 microns." We read like this: "The filter detains 95% of unwanted particles (5% will go further along the system), the linear dimensions of which are not less than 10 microns."

A brief tour of the brands

Cheap: Bosch, Hengst (Germany), Blue Print (UK), UFI (Italy), Puflux (France). Market share of the aforementioned brands tends to 70%

Also note the following budget filters: Profit, WIX, Starline (Czech Republic, Poland). The quality of their filters is not the highest, but meets many standards.

Determine the fake

We have already said that cheap filters should be at the bottom of the motorist's shopping list. However, the budget Starline on the car can be put, but the fake - in any case. Determining what is what is not difficult:

• Appearance. On the filter housing, you can find the article, engraving or stamping (on metal or plastic, respectively), the manufacturer's logo, as well as the product number;
• Price. Be wary of too cheap fuel filters, which fall in price during the holidays 2 times. Many times the price below the estimated level will never fall; discounts up to 35% are already very rare;
• Gaskets. The manufacturer uses sealing elements that practically do not react to the action of the fuel. The shape of the gaskets must be correct. Fake filters often do not have any gaskets at the hose connections to the filter itself;
• Packaging. A serious manufacturer spends money not only on the product, but also on its packaging. First, the company logo and its name should rush to your eyes. Secondly, the seal itself is of high quality. Thirdly, the design as a whole should be catchy and memorable; you will not find the original filter in ordinary white boxes;

• Build quality. Inside the filter, nothing rustles and does not hang out. All parts are well assembled; if they need to be glued, they are well glued;
• Metal processing. The equipment used at official factories allows to process metal well. It will not be scratches, chips, burrs. By the way, plastic cases are already hinting at a shameless fake - this material simply does not withstand high pressure in the system.

How to determine the quality of the product?

Even large plants sometimes produce defective auto parts. In the case of filters on the items listed below, you can also identify a fake, albeit relatively well executed:

• The paper was quickly clogged with debris. By the way that it is necessary to periodically remove the filter and visually examine it. If any part of the filter is quickly clogged, you can be sure: the product will last for 10 thousand kilometers maximum;
• Poor quality paper itself. It is almost impossible to determine visually. The bottom line is that small villi will be separated from the filter element, then entering the fuel system;
• Low winding density. Explicit savings on materials. If the winding density is low, the filtration quality will tend to zero.

Low-quality filters perform their task, but they have to be changed. more often  high quality.

Conclusion

Properly selected fuel filter to avoid problems in the long-term operation of the engine. It is especially important if you know little about the quality of fuel at gas stations whose services you are used to using.

If you complain about the engine during the inspection, the wizard is likely to study consumables. They will study the old filter and will say whether it is worth buying a similar one in the future. Your best assistant in choosing a fuel filter will be specialists, manuals and knowledge of the foregoing.

The effective functioning of the auto equipment depends on the purity of the fuel poured into the filling stations. The durability and performance of parts depend on the quality of the fuel and the presence of third-party impurities, dirt and water. For this reason, the fuel passes 2-4 stages of purification. Fuel is cleaned through a system of fine and coarse filters, eliminating coarse and fine contaminants.

What is a diesel filter cleaning?

Quality poured into fuel tank  fuel affects the performance and operational resource of many systems and components of the car. Diesel fuel sold at petrol stations often contains third-party impurities, the ingestion of which into a running engine can lead to deformation of its individual parts. Unwanted components of diesel fuel are retained and removed from it by means of fuel filters - special filter elements that clean the fuel from dust, rust, metal chips and water.

Diesel engines of the latest models more than other types of engines, need to be used in conjunction with the filter elements. This is due to the complexity and precision of their design, requiring the use of only high-quality fuel. In the case of engines running on diesel fuel, the degree of purification of diesel fuel should be maximized: gas filters installed in the fuel line should delay and prevent the appearance of dirt particles and other unwanted elements in the fuel up to 5 microns in size. At the same time in the diesel fuel should not contain moisture: its accumulation in the engine can provoke corrosive processes and reduce the strength of the metal.

Diesel fuel poured into vehicles with diesel engines is cleaned with special filters. TFs are classified according to the level of purification of diesel fuel into thin and coarse and are placed in fuel lines of the car in pairs, due to which the efficiency of cleaning diesel fuel increases several times.

Diesel cleaning filters vary by grade.

The structure of the fuel filter

In the overwhelming number of cases, diesel power units fail due to malfunctioning of the fuel system. The effectiveness of the filter and how thoroughly it cleans the fuel, affect the functionality of the motor and its service life.

The separation of water and diesel fuel is carried out by filtering the cassettes inside the gas filter: the design of such an element is straightforward and does not include complex parts. Exceptions are expensive models - they integrate moisture sensors and an accumulated water discharge system.

Most fuel filters have a similar design:

1. Diesel fuel, prepared for cleansing.
2. Obtained at the outlet of the pump fuel emulsion.
3. Separation of third-party impurities and condensation.
4. A mixture of purified fuel and moisture.
5. Element of a hydrophobic material.
6. A sump in which condensate accumulates.

Device almost all diesel filters similarly. Water and condensate accumulation in the gas tank can be avoided through regular full refueling of the car - automakers advise to do this at least once a week. On average, the working life of the TF ranges from 30 to 40 thousand kilometers, but it may vary depending on the quality of fuel used. The deterioration of TF operation affects the power of the power unit when climbing uphill, and its complete failure or continued operation in a polluted state can trigger engine overhaul.

The principle of the TF

TF works as follows:

• when fuel is passed through the filter, first of all it passes through the inlet fitting and then through the coarse filter benzofilter;
• the mechanical components of the diesel are held by the paper “curtains” of the filter;
• fuel, free from impurities, is supplied to the fuel line.

Automobile oil filters are manufactured using the same filter paper as fine filter benzers.

In the fuel systems of cars of foreign brands, fuel filters of a more complex design, consisting of three fittings, are installed. Since the fuel system of such machines consists of the main and additional lines, the fittings are placed as follows: two go to the main line, one to the additional one. The latter is intended to relieve the pressure in the system by dumping excess diesel fuel back into the fuel tank.

The choice of petrol filters for diesel engines: what to look for

When choosing a TF for a diesel power unit, several aspects are taken into account:

1. It is desirable to acquire only original filters designed specifically for diesel engines.  Today there is a huge range of gas filters on the markets, so the likelihood of stumbling on counterfeit is very high. Ideally, it is advisable to purchase fuel filters that are designed for a specific brand and model of car. For this reason, when selecting a benzofilter, you must rely on the catalog number - it must match the one that was specified by the manufacturer.
2. Filtration accuracy is calculated before purchasing a benzofilter. It is measured in microns and indicated by the manufacturer on the product packaging in the column "nominal and absolute filtration levels". By nominal is meant the 95% effectiveness of the delay by the filtering components of the particles. The absolute indicator determines the quality of fuel cleaning and the class of the benzofilter and in most cases is 98%. When choosing a TF, its specific type should also be taken into account - coarse or fine cleaning. The first type detains large impurities when filtering diesel fuel, the second - the smallest ones remaining in the fuel, which passed the stage of rough purification. The double cleaning method is today considered to be the most effective and widespread, since it is this that allows to achieve the best filtration of the fuel and provides engine protection. In addition, it allows you to extend the working life of both filters.
3. The lowest prices are always on low quality fuel filters.  High quality filtering components are distinguished by a high price, which forms the final cost of the TF. Modern models of filters are made using cellulosic, synthetic and composite materials. The most expensive are fully synthetic fuel filters, but they have the longest service life. The cheapest are cellulosic filters: in their design, the role of the cleaning element is performed by special porous paper. The combined models combine cellulosic and synthetic layers, which improves the quality and efficiency of fuel filtration.
4. The use of diesel fuel requires the installation of a water-fuel separator.  It is designed to remove condensate from the fuel and prevent moisture from entering the diesel fuel. The accumulation of water in the fuel can not only reduce the power and efficiency of the engine, but also disable it. Separators in most cases are installed simultaneously with the fuel filters.
5. The last requirement - the installation of the fuel filter should be carried out with the heating device.  In diesel fuel, when the ambient temperature drops, paraffin begins to thicken, which complicates the flow of diesel into the engine. To prevent this, a special heating device is installed in the motor.

Video: how to choose a fuel filter for a car

TF species

The fuel cleaning system includes a filter-sump, fine and coarse filters, fuel intake. The purification of diesel fuel from impurities is carried out in several stages as it passes through the filter elements.

For diesel power units produced filters of two types:

• prefabricated (their design provides for the replacement of individual parts);
• nonseparable.

The filtering elements of folding TP are made of ceramics and brass. Such models can be used repeatedly - they can be washed and cleaned from the accumulated dirt. The only disadvantage of such filters is their high cost.

Disposable filters are disposable, inside which is located the filter element. After clogging, they require a change to a new and clean.

Coarse filters

A filtering element that effectively cleans diesel fuel from foreign impurities whose particle size exceeds 0.05 mm. It consists of brass molded plates, between which there are calibrated slots that do not allow large particles of dirt, but at the same time easily conducting fuel.

The design of the wire-slot fuel filters resembles a glass with brass wire wound over it.

The gap between the turns of the wire is 0.07 mm. Fuel under the pressure of the fuel pump is passed through all the gaps between the wire, while the glass retains all impurities that are larger than the gap between the coils. The dirt accumulating on a glass is easily washed away during maintenance  car.

TF rough cleaning allows not only to clean the fuel from impurities, but also to prevent moisture from entering the vehicle fuel system. It retains the water contained in large quantities of diesel fuel, which subsequently sinks to the bottom, since it is heavier than diesel fuel. The design of the device includes a special filter that measures the total share of water in the fuel and alerts the driver.

A coarse filter protects the fuel system of the car from paraffin contained in diesel fuel. At low temperatures, paraffin crystallizes and can clog the engine, which disables it. Diesel fuel is cleaned of paraffins by heating it with a special heating element and passing it through a paper curtain, conducting current.

Fine filters

Small mechanical impurities no larger than 60 microns in size can cause a diesel engine no less harm than large ones. To clean the fuel from such inclusions can only fine filters. The design of such TF is designed in such a way that they can withstand high pressure in the fuel system. For their creation is mainly used steel and high-strength plastic.

In the housing TF are four sections, closed caps. In the center of each of them is placed a rod, on which an element is worn, shaped like a glass. Inside this element is filter paper. The contact area of ​​the filter and fuel is increased several times due to the corrugated surface of the paper. The cardboard frame protects the paper from damage. The frame has small holes through which the fuel passes through the paper. Such devices detain particles up to 4 microns in size. The corrugated paper in the filter needs to be replaced regularly.

Fine filters are best placed in front of the fuel pump, because at this point the system pressure is minimal, which protects the element from breakdowns and leaks. This arrangement also allows you to increase the service life of the pump, since it will work with purified high-quality fuel.

Device replacement policy

The frequency of replacement of the filter elements is specified by the manufacturer in the vehicle operating manual. The fuel filter selected for replacement should not only correspond to the size, but also have the necessary degree of filtration and throughput. In the manual, the manufacturer in most cases indicates the type of filter material and the filter itself. Installing an inappropriate fuel filter can significantly reduce the life of a car engine.

Planned replacement of fine and coarse fuel filters for most cars with diesel power units is carried out every 40 thousand kilometers. At the same time, official dealers recommend reducing the time interval by 30–50% under the condition that the vehicle is used in extreme conditions. For extreme conditions, the following conditions are accepted:

These factors adversely affect the operational life of the fuel filter, causing it to wear prematurely.

An unscheduled replacement of the filter element is carried out when the following signs of a car malfunction appear:

• “Troit” engine;
• set of turns is slow;
• sudden losses and power surges during the ride;
• increased fuel consumption.

When these symptoms appear, it is likely that they are caused by a fuel filter.

Fuel Filter Heater

In any climatic conditions, the most effective method to combat the crystallization of diesel fuel are heating systems - electric and combined. The principle of operation of such systems is based on the heating of diesel fuel and the melting of paraffin crystals formed in it. Filters for coarse and fine fuel cleaning, being critical components of the fuel system, most often need to install heaters. An electric heater is used to preheat a certain amount of fuel before the engine is started up, sufficient for the power plant to be built and to warm it up. Install it on the coarse fuel filter. Heated obratka maintains a high temperature of the fuel and does not allow it to thicken while driving.

The performance and service life of a diesel engine is largely dependent on the quality and purity of the fuel used. For both parameters fuel fine and coarse filters are responsible, thanks to which the diesel fuel is cleaned of foreign impurities and dirt. The use of such filter elements allows to extend the working life of the fuel system and the engine of the car.

Modern diesel engines are complex and precise mechanical systems, the smallest foreign particles capable of disrupting their work. Guarding the well-being of the engine are diesel fuel filters. Externally similar, they are radically different from the gasoline "brothers."

Device and principle of operation of diesel fuel filters

Before diesel fuel will be used for its intended purpose, it is cleaned of dirt and water. This is necessary because the fuel enters the injectors and cylinders under high pressure. In this case extraneous dust turns into an abrasive, quickly disabling parts. Dirty fuel is a major cause of premature diesel engine failures.  In their power systems are usually installed two fuel cells: coarse and fine cleaning. Solutions with one or three filtering steps are less common. The separation of functions between fine and coarse filters is not a dogma. For example, the removal of water from fuel can be assigned to both the first and second or both. It all depends on the design decision.

Dirty fuel - the main cause of premature failures of the pump, injectors, pistons and cylinders of diesel engines

The coarse fuel filter (PHOT) holds large foreign particles with a diameter of about 100–300 microns. Smaller fractions stop the fine filter (FTOT). The size of the collected dust depends on the requirements for the fuel by the motor.  So, the engines of the most advanced Common Rail system, the injectors of which operate under pressure up to 2.5 thousand atmospheres, need the cleanest fuel. The permissible size of foreign particles for them is not larger than 3-5 microns. Conventional diesel engines with plunger high-pressure fuel pumps (high-pressure fuel pumps) are less "capricious", since the operating pressure of the fuel in them is much lower. The location of FGOT in the power supply system is up to the preliminary pump that supplies fuel to the supercharger (high pressure fuel pump). FTOT is placed in front of the injection pump.

The coarse filter of diesel fuel is installed before the preliminary pump, fine - before the fuel equipment

The device filters coarse diesel fuel

A common design of PHOT is a collapsible glass with a replaceable filter element.

Common design FGOT-collapsible glass with a replaceable filter element

In the filter sump cleaning element is designed as a grid. Inside the glass can be placed additional elements that improve the functioning: a reflector, a damper, etc.

In the filter sump filter element is designed as a grid

Some cars use non-separable universal straight-flow PHOT in a transparent plastic case, externally similar to gasoline. For example, in the Mercedes-Benz W124 filter is installed WK 31/5.

In-line coarse filter diesel fuel is like a gasoline

Experiments on the installation of a diesel engine on the serial a car  in Europe began in the thirties of the twentieth century. For example, in 1936 there was a 45-strong version of the Mercedes 260D with the brainchild of Rudolf Diesel under the hood.

  Oleg Polazhinets

The device filters for fine cleaning of diesel fuel

Fundamentally, they differ in the properties of filter elements and the size of the dust retained.The filter element is the main part of the FTOT. In addition to it, the filter can be equipped with a separator for separating moisture from the fuel, a tap to drain accumulated water and a sensor for its presence.

In addition to the filter element, the FTOT can be equipped with a separator for separating moisture from the fuel, a tap for draining accumulated water and a sensor for its presence.

Structurally, these elements are performed as non-separable and collapsible. In the second case, either a cartridge or a cartridge is used as a replacement element. The cartridge — a packageless replaceable element made of filter paper or other finely porous material — is installed in a plastic, aluminum, or steel housing. FTOT cartridge - the same cartridge, but placed inside its own body. Some fuel cartridges can also be used to clean the oil. The fuel filter consists of two elements: a cartridge and a cap.

Photo Gallery: filter designs

   Non-dispersed fine filter assembled in a closed housing    If necessary, replace only the cartridge collapsible filter    Inside the collapsible filter is a replaceable cartridge    Cartridge filter consists of a cap and cartridge    Replaceable cartridge element - the same cartridge assembled in a separate case

Video: filter device

Selection

The right strategy for choosing a fuel filter is to follow the recommendations of car manufacturers.  They are designed to meet the needs of the engine. You should not experiment, installing the wrong filter only for the reason that it is cheap.

Some motorists are trying to compensate low quality  cleaning by frequent replacement of the fuel cell. This is the wrong approach. The main task of the filter is to prevent foreign particles from entering a fuel apparatus and cylinders larger than a certain size. Filtration is one of the characteristics that does not change during operation. Neither the old nor the new element, which is not able to keep small particles, will not save the engine from breakage.

Filtration is one of the characteristics of the filter that does not change during operation.

Filters similar in parameters are produced by 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 install on new cars. For the selection of a suitable filter, use the online catalogs. Choose only those models in the description of which there is a direct recommendation for your car.

Photo Gallery: Filters for cleaning fuel known brands

Bosch filters  - one of the cheapest among famous brands    Mann offers the widest range of filters for various purposes.    Delphi - one of the few companies that have mastered the production of filters for diesel engines Common Rail

   Knecht-Mahle - prestigious German brand    The Italian company UFI delivers filters to the Volkswagen assembly line

Video: fuel filter overview

Replacement policy

Signs of the need to replace fuel filter cleaning are as follows:

• difficulty stopping the engine,
• spontaneous motor stop,
• low power
• noisy engine operation
• heavy black smoke from the exhaust pipe.

Wait until the symptoms listed are dangerous. Diesel engine does not tolerate inattention. Delay in the replacement of fuel filters reduces the life of the engine and provokes premature failure. To avoid trouble, change the filters at least as recommended by the car’s manual.

The Belgian importer Volga already in 1960 began to install on the "twenty-first" several types of atmospheric diesel engines, of course, of foreign manufacture. True, the car at the same time "stopped driving", but in Western Europe, 50 years ago, saving was much more important than dynamics.

  Oleg Polazhinets

Manufacturers are constantly improving diesel fuel filters. The estimated resource of modern replaceable filter elements reaches 90 thousand kilometers. Practical recommendations of car manufacturers are much more modest, which is probably due to two factors. Firstly, the low quality of fuel greatly influences the service life. There are no clogging indicators in the filters, so it is impossible to check the condition of the filtering elements without disassembly, and it is better to be safe than to cause significant damage to the engine. Secondly, the corporate service brings a significant profit, from which the right holders of brands are in no hurry to refuse.

Unified recommendations for replacing filters for all diesel cars does not exist. Usually they are 25-40 thousand kilometers. The cleaner is coarse, if there is one, and there is no special recommendation in the car’s manual; they are changed along with the main element of fine cleaning.

The figures given are only generalized data that are not intended for practical use. Look at the "primer" of your car. It is possible that its manufacturer considers it appropriate to change the filters more often. For example, for diesel cars Renault Duster in 2015, a filter resource of 20 thousand kilometers was set, up to this date it was only 10 thousand kilometers.

Low-quality fuel significantly reduces filter life. In order to harm the engine, it is sometimes enough just one refueling. Having noticed something amiss after visiting the gas station, drain the suspicious fuel and fill the tank with a well-known quality one. Replace the fuel filter as soon as possible, even if signs of unstable operation have disappeared.

Heated diesel engine cleaning filter

The peculiarity of the winter operation of diesel fuel is the crystallization of paraffins in it.  Due to the low temperature, paraffins precipitate, clogging the fuel filter and fuel lines. Winter fuel is more stable than summer fuel, but it can also harden.

Due to the low temperature, paraffins precipitate, clogging the fuel filter and fuel lines.

The correct method to combat the crystallization of paraffins is the heating of the fuel cell.  In some cars it is implemented constructively, for example, in Renault Duster.

In some cars, the heating is implemented constructively, for example in the Renault Duster

You can equip any car with heating by installing a heated filter instead of a regular one or in addition to it.

It is possible to equip any car with heating by installing a heated filter instead of a regular one or in addition to it

The problem is solved independently and with minimal costs by installing an electric bandage heater on the existing filter.

With minimal cost, the problem of heating is solved by installing an electric bandage heater on an existing filter.

Video: DIY fuel filter heater

Reliable fuel filter is a prerequisite for long-term operation of a diesel engine. It is impossible to save on the filter. Repair of the motor will cost more.