In the eyes of the maintenance master, it is a common phenomenon that the engine oil temperature is high or the water temperature is high. Here, tell everyone what to do when the oil temperature and water temperature of the engine are too high.
The water temperature of the excavator repair is high: Why is the water temperature high?
The function of the water tank is to dissipate heat. The principle is to continuously derive the heat through the engine fan.
How does the excavator "fever" cool down?
Common problems with high water temperatures:
1. The thermostat is stuck and cannot be opened. At this time, the water can only go through a small cycle, not through the radiator.
2, the inside of the water tank is dirty, the water is not smooth, this can use the temperature gun to detect the temperature above and below the water tank, blocking the temperature below will be very low.
3. The fan speed is not enough and the clutch is faulty.
4. The rubber strip around the radiator is damaged or not. At this time, eddy current is generated, and the hot air is circulated, which cannot achieve the cooling effect.
5, for the fifth point, everyone is easy to ignore, is it will be false alarm, the sensor is broken, it is also possible, the computer is very wood, because it only looks at the data does not look at the truth.
The oil temperature of the excavator repair is high: Why is the oil temperature high?
How does the excavator "fever" cool down?
In fact, the oil temperature is high and the water temperature is high. There are also large and small cycles. It is not through the thermostat. He has an oil return check valve. If this valve is stuck, the oil temperature will be high, and the others will be the same as the water temperature.
Of course, the large excavator is driven by a fan pump to adjust the speed of the fan motor. There is also an overflow device. Generally, the oil temperature is high. Checking these places can be solved.
1. The oil temperature is too high and directly harms the engine - it may cause high maintenance costs
The excessive temperature of the engine means that the engine oil temperature and water temperature exceed 90 °C.
Due to the principle of thermal expansion and contraction, it is easy to reduce the engine clearance after the temperature is raised, resulting in severe wear or "cylinder".
When excessive heat generation exceeds heat dissipation, the temperature of the bearing bush will rise, the local temperature will reach the melting point of lead, and the lead and copper in the bearing bush will melt, eventually causing severe ablation of the crankshaft and bearing or creating a "winding axis". The consequences could be disastrous.
Therefore, when the temperature of the oil and water are too high at the same time, the oil temperature should be lowered first.
One point to note: the temperature of the oil can slow down the temperature rise.
The role of the water tank is to reduce the oil temperature of the engine. The oil drop temperature usually adopts the method of “download, low speed”. At this time, although the coolant exchanges heat at a high temperature part for a long time, the water flow speed is slowed down, and the heat dissipation time is prolonged.
At the same time, due to the reduced load and reduced speed, the heat generated by the friction of each moving part is also reduced accordingly.
Therefore, the oil temperature can not only reduce the heat generated by the engine, but also indirectly reduce the heat absorbed by the coolant, which can also slow down the temperature rise.
The first precipitation temperature has a great influence on the oil pressure of the engine shaft.
As we all know, the precipitation temperature is generally a method of "download, high speed". When the rotation speed is too high, the inertia force and centrifugal force of the piston group will be increased, so that the load of the crankshaft bearing is increased.
At the same time, the relative friction speed of the journal and the bearing bush will also increase, so that the heat generated per unit time will increase, the oil volume of the oil pump will decrease, and a large amount of oil will be thrown out from the main oil passage, resulting in no friction surface of each machine. Sufficient lubricating oil will increase wear and the oil temperature will rise further.
Through the above information, I believe that all of you have already been very clear about the cause of the "fever" of the excavator. If you encounter the situation that the oil temperature and temperature rise at the same time, you should first lower the oil temperature, then lower the water temperature, and replace it in the summer construction work. It is suitable for summer antifreeze and timely cleaning the dirt of the water tank, and can also enhance the heat dissipation effect of the excavator.