At present, more and more customers will give priority to Cummins engine when they choose engines for special purpose vehicles. Although its price is relatively high, its quality and technology are first-class in China. How much do you know about the use and maintenance of Cummins engine?
1. What is the normal operating water temperature?
Generally speaking, the best water temperature of diesel engine is about 95 ℃, which is the most energy-saving. Cummins engine can accurately control the water temperature in this range. After normal operation, the water temperature is between 85-97 ℃. When driving, you can observe whether the instrument exceeds the standard. When the water temperature exceeds 107 ℃ (red area), the engine will automatically limit the torque, the engine fault light and the water temperature and water level alarm light will be on, and when the stop indicator light is on, it should be stopped immediately.
2. How to control the water temperature?
For engines, the key is the fuel saver and fan. The engine uses two different thermostats at the same time. The first one opens at 82 ℃ and the second one opens at 88 ℃. The fan used by the engine is an electronic silicone oil fan. When the water temperature exceeds 93.7 ℃, the fan starts to work; when the water temperature rises to 97.7 ℃, the fan works at 100%, that is, the fan works at the highest speed.
3. How much oil pressure is during operation?
Cummins engine adopts new R & D technology, and the oil pressure can meet the use demand and can achieve 100000 km maintenance and reduce the fuel consumption. The engine design low idle oil pressure is more than 1.24bar, and the rated speed is more than 2.07bar. Generally, the engine cold start oil pressure is about 2.2bar. When the engine oil is lower than the set value, the engine oil alarm light and engine fault light will be on. When the stop indicator light is on, the engine should stop immediately.
4. What are the advantages of low oil pressure?
Based on the special design of lubricating oil passage, the engine can quickly establish hydrodynamic pressure, and the oil pressure is 50% lower than that of the industry, which can meet the lubrication requirements of each motor pair of the engine, which greatly reduces the power loss. The engine also adopts the rotor oil pump, which is directly driven by the crankshaft gear, with high efficiency, low mechanical power loss and stable oil pressure at low speed.
5. Why is there a lower exhaust?
When the engine is working, a small amount of gas will enter the crankcase through the gap between the piston ring and the cylinder to form the normal blowby, that is, the lower exhaust as we usually call it. Its main components are exhaust gas, engine oil vapor, a small amount of water vapor, etc. it will reduce the performance of engine oil, accelerate the oxidation and deterioration of engine oil. In order to prolong the service life of engine oil, reduce the wear and corrosion of parts, and prevent engine oil leakage caused by too high crankcase pressure, crankcase ventilation must be implemented, and the lower exhaust must be discharged in time.
6. How to judge whether the engine oil consumption is normal?
The working principle of the engine determines that the engine is accompanied by proper oil consumption under normal conditions. One part is the inevitable exhaust gas caused by the steam consumption of some oil, the other is that the remaining oil left by the piston ring scraping is burned out in the combustion chamber!
The ratio of oil quality to fuel quality of national standard engine shall be limited, and it shall not exceed 0.3%. Cummins engine oil consumption standard does not exceed 0.15%, that is, it consumes 1000L diesel oil, and engine oil consumption is less than 1.5L. Due to the unique cylinder design of the engine and the exclusive patent of crankshaft respirator, it greatly reduces the generation of exhaust gas, reduces the oil consumption, and can remove the high-temperature oil steam more timely, extend the service life of the oil, so as to ensure that the engine can meet the requirements of 100000 km maintenance. Oil consumption is also closely related to oil grade, climate temperature, load condition, etc., but as long as it is within the normal range, the engine performance and service life will not be affected!
