Take note of maintenance of SCR tail gas after treatment system

1. The urea pump filter element of SCR system needs to be replaced every 3 years or 100000 km. If the application environment is bad and the urea aqueous solution is seriously polluted, it shall be replaced according to the actual situation. Before replacement, the external surface of the urea pump shall be cleaned, and the filter element area shall be strictly prevented from external pollution during installation. The filter cover shall be tightened with a torque of 20+5nm. Replacement steps of urea pump filter element.

2.the sealing plate at the bottom of the urea nozzle is a disposable part, which needs to be replaced after each disassembly. Do not use sharp tools to pry the edge during replacement. Use tweezers to move the three disc contacts. Clean the sealing area after removal, but avoid touching the urea nozzle, and then reinstall a new sealing disc

3. the urea solution shall be added to 100% of the maximum liquid level in the urea tank. When the urea solution is consumed to the remaining 20%, the urea solution shall be added; Open the drain plug at the bottom of the urea tank for cleaning when the engine is maintained every year to drain the sediment in the tank; Check the urea tank irregularly. If white crystals are found at the vent valve or liquid filling port, wash it with clean water or wipe it with wet cloth. If the vent valve is blocked, clean it with clean water or replace it; Replace the filter screen in the box after 2 to 3 years of service; Irregularly check whether the plug-ins and pipe joints are in good condition

4. the urea pipeline shall be installed correctly, otherwise the system will not work. Before installation, ensure that both ends of the pipeline are well protected to prevent dirt and impurities from entering the pipeline and then entering the system, resulting in system failure. The urea pipe shall not be bent during installation, otherwise the system will not work

5. the sensor harness shall be prevented from contacting with high-temperature objects. The ambient temperature sensor shall be installed at a position that can objectively reflect the ambient temperature to avoid the impact of other heat sources on the sensor measurement

6. check the connection between the system harness cable and the connector to ensure that there is no visible wire exposed in the air, the harness insulation sheath should be complete, the protection measures should be good, and there should be no external wear; The connector shall be inserted in place without oil, mud and other dirt.