In November 2019, Hitachi Excavator Maintenance Company organized an excavator maintenance industry association. The chairman of Hitachi Excavator Maintenance Company and the vice chairman of Hitachi Excavator Maintenance Company gave a keynote speech on "Excavator Maintenance and Repair". Hitachi Excavator Maintenance Company gave a keynote speech titled "Causes of Excavator Burning Oil". The reasons and solutions were shared; afterwards, representatives from all over the country spoke freely and specifically analyzed the reasons for the excavator to burn engine oil.
The six main reasons why excavators burn engine oil are as follows:
1. Use engine oil of poor quality or viscosity grade that does not meet the requirements. Low oil quality grades will lead to increased wear and tear, resulting in oil burning.
2. The matching clearance between the piston ring and the cylinder wall is too large, causing oil burning. In addition, the poor sealing performance of the valve sealing ring, the damage of the crankcase ventilation valve or the blockage of the crankcase vent will cause the oil to enter the cylinder with the crankcase gas to participate in combustion.
3. Engine oil burning caused by excessive oil filling. When the oil filling exceeds the center line, because the oil pressure is too high, the splash lubricated part of the engine will escape into the combustion chamber too much.
4. The turbocharger leaks oil. The turbocharger is installed in the front end of the exhaust pipe, and the working temperature is very high. When the turbine and the pump wheel are running at full load, the speed can reach ten thousand revolutions per minute. The turbine shaft uses oil-lubricated floating bearings, and the car has an oil passage leading to the turbocharger. Oil leakage from pipes or bearings may cause oil to seep from the turbocharger into the exhaust pipe. When the temperature of the exhaust pipe is high, the engine oil is baked and turned into blue smoke to be discharged.
