There are three types of fuel filters: diesel filters, gasoline filters and natural gas filters.
In order to achieve higher separation efficiency, the first stage is an oil-water separator, and the first stage is a diesel fine filter. Wear and sticking can even worsen the combustion process of diesel. The water removal method of the diesel filter system is mainly sedimentation in the mechanical fuel system. In the era of national three or above emissions, diesel engines mostly use high-pressure common rail fuel systems, and water removal methods mostly use filter paper.
Gasoline filters are divided into carburetor type and EFI type. For gasoline engines using carburetors, the gasoline filter is located on the inlet side of the fuel pump, and the working pressure is low. Generally, nylon shells are used. The gasoline filter is located on the outlet side of the fuel transfer pump and has a high working pressure, usually with a metal casing. The filter element of the gasoline filter mostly uses filter paper, and some also use nylon cloth and polymer materials.