The disassembly and assembly of diesel filter cartridges is simple,but many of them have difficulty starting,frequent air intake,and oil leakage after replacement,mostly due to errors in disassembly details.Strictly follow the process operation.

　　Turn off the engine and stop the machine before disassembly,and release the residual pressure in the low-pressure oil circuit.Spin on type:Prepare the oil container and unscrew the old filter element;Paper core type:Remove the end cover of the filter cartridge casing and take out the old paper core.

　　**Key point:Before installing the new filter element,clean the sealing surface of the filter element base,and remove the old sealing ring,oil stains,and impurities.The old sealing ring must be removed,and it is forbidden to leave the old ring on the base and stack a new ring,which will inevitably cause oil leakage.**

　　Apply a thin layer of clean diesel oil to the sealing ring of the new filter element,do not apply butter.Butter will dissolve into the oil circuit when encountering diesel,blocking the needle valve of the fuel injector.After manually screwing the filter element into place,turn it 3/4 of a turn.Do not use tools to forcefully twist it,as thread slippage and shell deformation can directly cause oil leakage.

　　Paper core filter element,the filter element should be positioned correctly,and the end cap bolts should be evenly and diagonally tightened.Do not use unilateral force to crack the shell.The assembly of the oil-water separator is completed,and the bottom drain plug is tightened in place to prevent air and oil leakage.

　　After assembly,repeatedly press the hand Oil Pump to completely exhaust the air in the entire fuel circuit until the hand oil pump becomes hard.**Do not continuously ignite the motor for a long time.Failure to exhaust air can cause damage to the motor and also introduce a large amount of bubbles that can damage the high-pressure oil pump.Exhaust the air before starting the engine.

　　After starting,idle and observe whether there is any leakage in the filter base and joints;Check that there is no oil leakage from the drain port of the oil-water separator.Test drive and observe whether the startup is smooth,whether there is any shaking,and whether the engine stalls.

　　High frequency stepping points during disassembly and assembly:forgot to remove the old sealing ring,lubricated the sealing ring with butter,forcefully twisted the threads,and directly hit the motor without air discharge.Proper cleaning,proper installation of sealing rings,and thorough ventilation are necessary to ensure stable operation of the fuel system.