The coolant drain of the diesel engine is at the lowest position of the engine block. Strictly speaking, not only the diesel engine, but also the coolant drain port of all water-cooled cycle engines are located at the lowest place of the engine block, so as to drain the coolant as clean as possible, so as to avoid unnecessary losses caused by freezing the engine block in cold weather.

The position of the diesel engine coolant drain is on the lowest parallel line of the engine body cooling water. Some diesel vehicles have waterproof switches on the engine block. The diesel engine drain switches are generally self flowing and installed at the bottom of the engine block, which is easy to find. In this way, the cooling water inside the engine can be completely drained to prevent residual frost cracking in winter.

The diesel filter is used to filter harmful impurities and moisture in the fuel system, protect the normal operation of the engine, reduce wear, avoid blockage, and improve the service life of the engine.

The filter element of diesel filter is mostly made of filter paper, or felt or polymer material. The filter element of gasoline filter is mostly made of filter paper, or nylon cloth or polymer material.