A fuel filter can be found in most internal combustion engines. In fact, it performs the most important function for modern cars that are sensitive to the quality of motor fuel - cleaning from unwanted substances and dirt using special cartridges with filter paper. Thus, filters increase engine power, because the fewer pollutants in the fuel, the more efficient combustion occurs.
Together with an expert, we understand the secrets and intricacies of high-quality purification of motor fuel. In our material we tell you where the fuel filter is located, how often it needs to be changed, how much it costs and where you can buy it.
Purpose of fuel filters
All internal combustion engines are equipped with filters to clean the fuel before entering the cylinders.
They hold particles larger than the pore diameter.
- Fuel contaminants can be clay particles, paint components, rust elements or trapped debris.
- The fact that they end up in the fuel cannot be blamed on the manufacturers, because at the refinery, before the fuel is sent for sale, it is carefully filtered.
- Sources of dirt often turn out to be tanks, containers, canisters into which fuel is often poured and pumped before refueling the tank of a car.
Each time fuel is poured into a container, sediment rises from its bottom, which was previously lying at the bottom of the container.
A similar mixing occurs when transporting a tank to a gas station or dump point. In this way, unsettled pollutant particles are poured into vehicle tanks.
Causes of filter element clogging
We’ve sorted out the signs of a clogged fuel filter, now let’s look at the reasons leading to a clogged filter device:
- Filling a car with fuel of questionable quality. If your car is often refueled at small gas stations (not proven in the car market), keep in mind: selling gasoline and diesel fuel is a good business, therefore, in order to reduce production costs and increase turnover, gas station owners add various additives and resins that can clog not only the filter, but also and the entire system.
- Insufficient fuel purification. After the production of a combustible mixture, it is transported, therefore, from canisters, tanks, reservoirs, particles of paint, dirt, and harmful impurities may enter the specified liquid.
- Air dustiness. It's no secret that our cars are operated in far from ideal operating conditions; the presence of dust particles, dirt, insect particles, and plants in the air is inevitable.
It is impossible to eliminate these reasons, so monitor the condition of the filter device and follow the dealer’s recommendations regarding the scheduled replacement of consumables. Replace the filter device yourself if the machine is not under dealer warranty.
Why do you need to replace the fuel filter?
The need for filtration is caused by the negative effects of pollutants on the injection system and the engine piston system. Over time, the filter becomes clogged and the amount of fuel driven through it by the fuel pump over a certain period of time decreases.
When accelerating or driving uphill, there may not be enough fuel, and the car significantly reduces power.
- If nothing is done in the future, it will move jerkily and stall, then it will not start at all due to lack of fuel.
- Motorists with extensive experience know when it is time to change the fuel filter - at the initial signs of blockages.
- It is better, without waiting for these signs to appear, to change the filter in accordance with the instructions of the car manufacturer.
Any service book states the mileage, upon reaching which the filter must be replaced. When it is known that low-quality fuel is being used, changing the fuel filter will be needed in a shorter time.
How to make a choice
When choosing a fuel filter, you should pay attention to:
- Device bandwidth. The coincidence of the diameters of the filter inlet and outlet fittings with the diameter of the fuel pipe tube is a sure sign of suitability, but it never hurts to clarify the parameters;
- Filter service life declared by the manufacturer. Avoid purchasing fuel filters, the manufacturers of which guarantee the constant performance of the device throughout the entire service life of the vehicle;
- Manufacturer's reputation. Little-known manufacturers can place a plastic mesh wrapped in a blotting cloth in the filter, sell the batch at a dumping price - and disappear from the market forever.
Types of fuel filters
Filters differ in their structure. They are installed based on the type of fuel system.
There are three types:
- Carburetor type. The initial stage is a mesh in the tank, then there is a fine filter, and finally a small mesh at the inlet to the carburetor;
- Injection view. There is also a large mesh in the tank, then a pump filter for gasoline is installed, enclosing a fine cleaning part;
- Diesel - here the analogy of injection cleaning is used, but an additional stage is connected in the form of separation.
Diesel filters differ in that the type of such engine is considered very vulnerable, therefore the fuel for such systems must be cleaned in the best possible way. In this case, the fuel of the car undergoes three stages of purification - in the gas tank, then coarse and fine cleaning.
A diesel fuel filter is designed to prevent water from entering the combustion chamber. Therefore, a high-quality cleaning filter for a diesel engine is more expensive than a cleaning unit for a gasoline engine. According to the design, filters are divided into prefabricated and non-dismountable types.
When a non-separable gasoline cleaning unit is installed in a car, then when it becomes unusable, the entire fuel filter must be replaced. Prefabricated types do not require complete replacement - just replace the filter part.
After how long to change
The recommended mileage between replacements of a submersible fuel filter in gasoline internal combustion engines is 40-50 thousand kilometers, and a flow filter is 10-15 thousand kilometers. The harsh conditions of the northern regions of Russia (frost, high air humidity, fuel supplies in barrels) can reduce the inter-regulatory vehicle mileage to 10 thousand km. Diesel fuel filters should be changed at least twice as often as gasoline filters - every 5-10 thousand kilometers.
The fuel filter of a carburetor engine, attached to the gas line hose with two clamps, is easy to replace with your own hands. And servicing of injection and diesel engines should be carried out by qualified service station workers to avoid damage, incorrect installation or airing of the power system.
What is the replacement period?
In the average version, manufacturers recommend replacing filters after 30,000 km. Many car owners, through experimental observations, also came to this mileage figure.
Symptoms that the filter needs to be changed may include:
- Triple
- And turning off the engine
Of course, not everything can be exactly like that. When you refuel at gas stations known for their high quality fuel, adhere to a leisurely driving style, and rarely drive on rural roads, then you can greatly increase the frequency of filter changes. But in practice this rarely happens.
Possible faults
The symptoms of a clogged fuel filter are quite varied. Please note that the following signs may indicate not only a breakdown of the filter device, but may also indicate the causes of a malfunction of the control system. To be on the safe side, you can make sure that the reason is in the fuel filter using the following method: take a pressure gauge and connect it to the nipple located on the fuel injector frame, then start the car and measure the pressure of the fuel mixture. If the pressure gauge shows parameters below those provided by the car dealer, we can talk about a fuel filter malfunction.
Clogged filter
When the throughput of the filtering device decreases, interruptions in the operation of the power unit are observed:
- fuel consumption increases;
- the car stalls at idle;
- failures in engine operation are observed when the speed increases;
- it is difficult and sometimes impossible to start the engine;
- The power of the power unit decreases, it begins to triple;
- it is possible to brake the car while driving without pressing the brake pedal;
- When moving up an inclined plane, the vehicle jerks.
All these signs are observed if the filter is clogged; its increased resistance to the intake air flow creates additional load on the engine.
Signs of a blockage
Does a car enthusiast need to know when to change the filter? A number of features are known for this purpose. All symptoms are caused by poor fuel supply.
We provide the main signs of a fuel filter failure:
- Severely reduced power;
- Uneven engine operation - often detected by sneezing or jerking of the car;
- Increased fuel consumption. This sign is indirect, it is not always connected with this.
In the first stages of blockage, these signs of blockage are not clearly expressed, so drivers do not notice alarm bells.
Only after the fuel supply has completely stopped do the owners begin to think about the reason. There are cases when the car did not start due to the fact that gasoline could not squeeze through the filter.
Fuel consumption
Fuel consumption is the first obvious sign of a clogged filter. Every driver can determine it, just drive the estimated distance. Experienced motorists know how much gasoline is consumed on a particular road and distance. Obviously, if the filter is clogged, the consumption will increase noticeably. Fuel enters the internal combustion engine in small quantities; due to the concentration of debris in the filter, the composition of the combustible mixture changes. This explains the fact that the power and speed of the car decrease; the driver sometimes needs to press the accelerator harder.
There is also a special device that allows you to monitor the process of clogging of the TF, signaling the need to replace it. This tool can be used to determine when replacement will be required and will reduce damage to the fuel supply. This is a sensor that allows you to reduce wear on the fuel supply system, as well as reduce the cost of consumables and replacement elements.
Fuel filter and fuel consumption
However, such indicators are not installed by all vehicle manufacturers. However, it is not difficult to detect a clogged filter without a sensor. In addition to the above characteristics, the clogged TF can be calculated directly. To do this, you must first find it: on most cars it is located near the gas tank under the bottom. Then loosen the fixing clamps, lower the end of the fuel drive into a glass container, and be sure to place the car itself at neutral speed. In this case, the engine must operate in idle mode - if fuel flows at a lower speed than from the tank, it means that the fuel pump is clogged.
In fact, replacing the TF is not particularly difficult, especially if we are talking about a gasoline unit. It is necessary to prepare tools, which include a set of screwdrivers, gloves and a container for collecting liquid from the old TF. To avoid making any mistakes, it is recommended to use the instructions for a specific car. Installation of the TF must be carried out strictly according to the instructions. The new filter must be installed according to the direction of fuel movement.
Shift instructions
For most car brands, this procedure is not too difficult.
Basically, filters are installed in the following places:
- Under the bottom of the car - on the injection system;
- In the engine compartment in front of the high pressure pump - for diesel engines;
- In the engine compartment in front of the injection pump, there is a break in the gasoline line - on the carburetor;
- A coarse mesh is installed in the tank along with a gasoline pump.
To avoid dousing your hands and car parts with fuel, before the procedure it is advised to release the pressure in the lines, which is constantly present on injection models of cars. To do this, you will need to find the spool on the ramp, place a small container and press the valve.
Safety precautions for replacement
If the driver nevertheless decides to replace the filter himself, he must adhere to safety measures. The procedure is best carried out in a spacious, ventilated room, since the work takes place with fuel vapors. They tend to catch fire from a small spark.
It is best to keep a fire extinguisher near you and also refrain from smoking. Before removing the filter, the pressure must be released. It still remains even after turning off the engine. To prevent sparking, you need to remove the battery terminals.
The listed rules will help you carry out the procedure quickly and safely.
How does the replacement take place?
The fuel filter is replaced in the following order:
- On a car with carburetors, just unscrew the clamps and pull the hoses out of the fittings, then unscrew the consumable body and replace it with a new product.
- On machines with fuel supply from an injector, these actions must be carried out from the inspection hole or lying under the bottom.
- On the diesel version, you need to pull out the tubes, remove the cover and remove the littered paper insert.
The location of the filter and the replacement method may differ depending on the make and model of the vehicle.
For example, on a gasoline car, instead of a round barrel that cannot be disassembled, a housing with a filter paper insert can be installed. In this case, this core changes. When you need to clean or change the screen in the tank, then you need to remove the gasoline pump.