Fuel Filter

Fuel Filter
 
The function of the fuel filter is to prevent particles, water and impurities in the fuel, and to ensure that the precision parts of the fuel system are protected from wear and other damage.
 
 
working principle
The fuel filter is connected in series on the pipeline between the fuel pump and the throttle body inlet. The function of the fuel filter is to remove the iron oxide, dust and other solid impurities contained in the fuel to prevent the fuel system from clogging (especially the fuel injector). Reduce mechanical wear, ensure stable engine operation, and improve reliability. The structure of the fuel burner is composed of an aluminum shell and a stainless steel bracket. The bracket is equipped with high-efficiency filter paper sheets, which are chrysanthemum-shaped to increase the circulation area. The EFI filter cannot be used in common with the carburetor filter. Because the EFI filter often bears the fuel pressure of 200-300KPA, the pressure strength of the filter is generally required to reach 500KPA or more, and the carburetor filter does not need to reach such a high pressure.
 
 
Diesel filter
The structure of the diesel filter is roughly the same as that of the oil filter. There are two types: replaceable and spin-on. But its working pressure and oil temperature resistance requirements are much lower than those of oil filters, and its filtering efficiency requirements are much higher than those of oil filters. The filter element of the diesel filter mostly uses filter paper, and some also use felt or polymer materials.
Diesel filter can be divided into diesel water separator and diesel fine filter. The important function of the oil-water separator is to separate the water in the diesel. The presence of water is extremely harmful to the fuel supply system of diesel engines. Rust, wear, and seizure can even worsen the combustion process of diesel. Due to the high sulfur content in Chinese diesel, when combustion occurs, it will even react with water to form sulfuric acid to corrode engine parts. The traditional water removal method is mainly precipitation, through the funnel structure. Engines with emissions from National III and above put forward higher requirements for water separation, and the higher requirements require the use of high-performance filter media.
Diesel fine filter is used to filter the fine particles in diesel. Diesel engines that emit from the national three or above are mainly aimed at the filtration efficiency of 3-5 micron particles.
 
 
Gasoline filter
Gasoline filters are divided into carburetor type and electronic injection type.
For gasoline engines using carburetor, the gasoline filter is located on the inlet side of the fuel transfer pump, and the working pressure is relatively small. Generally, nylon casing is used. The gasoline filter of the EFI engine is located on the outlet side of the fuel transfer pump, and the working pressure is higher. , Usually a metal shell. The filter element of gasoline filter mostly uses filter paper, but also uses nylon cloth and polymer materials.
Gasoline filter because the combustion method of gasoline engine is different from that of diesel engine, the overall requirements are not as stringent as diesel filter, so the price is cheap.
 
 
Maintenance
The fuel filter is a consumable, it needs to be replaced and maintained regularly during the use of the vehicle, otherwise it will not be able to provide qualified protection. Please refer to the instructions on the products provided by each filter supplier for the specific replacement cycle.
Suggested replacement time: every 20,000 kilometers of the car. [1]
Precautions for replacing gasoline filter
(1) After replacing and installing the gasoline grid and the engine oil grid, pay attention to the sealing of the interface and be alert for oil leakage;
(2) For air compartments and air conditioning compartments, ensure the overall sealing after replacement;
(3) Take care of the gasoline grid and try to use the matching mark gasoline specified by the automobile manufacturer.
The filter is marked with arrows on the inlet and outlet ports. Do not install it backwards when replacing it.
 
 
The development of fuel filter
Chinese filters have been through for more than 30 years. Bengbu initiated the establishment of national testing standards in Bengbu in the 1980s, which promoted the rapid rise of the entire industry. In particular, the Wenzhou model shined brightly, from auto trim to auto parts, from exterior to automobile. There is a qualitative leap in the interior, but the fuel filter, that is, the gasoline filter, has not been paid attention to. It is the product with the least frequency of replacement among the 4 filters, and the most easily overlooked product. The gasoline filter has been latent for many years, and it follows the car. The speed is accelerating, the oil price is rising rapidly, the environment is changing, the technology is environmentally friendly, and the carbon emission is reduced. The gasoline filter is changed from external to built-in. From the carburetor to the electronic fuel injection, the built-in gasoline filter has become a trend.
 
Performance characteristics of fuel filter
If the filter is installed in the fuel line, it is called an external filter (External); conversely, the internal filter (Internal) refers to the filter installed inside the fuel pump and fuel tank. Among them, the fuel tank filter or its protective sleeve is generally considered to be a maintenance-free component.
The fuel filter of many imported cars uses a drum tube connection (BanjoFITtings). In order to ensure the reliability of the connection and sealing, the same gasket must not be used repeatedly. In addition, even if a brand-new gasket is used, the tightness of the connection must be checked. When the fuel system needs to replace the "O" ring, it is necessary to ensure that the specifications and model of the "O" ring are correct, and to check whether the elasticity and hardness of the ring are appropriate.
The fuel system without loop has only one internal filter (in the fuel tank). Although this all-in-one pump, filter, and delivery unit are expensive, when fuel delivery is blocked or When the engine performance decreases due to this, proper maintenance must be carried out in time. At the same time, it is necessary to check all the faults in the fuel line and the rupture and curling of the hose clamp.
 
 
Replacement cycle
The recommended replacement period of the fuel filter should vary according to its own structure, performance and purpose, etc., and cannot be generalized. Most automobile manufacturers recommend a replacement period of 48,000 km for normal maintenance of their external filters; the recommended replacement period for conservative maintenance is 192,000 to 24,000 km. If in doubt, please refer to the owner’s manual to find the correct recommended replacement period.
In addition, when the filter hose has aging or cracks caused by dirt, oil, etc., the hose needs to be replaced in time.