Symptom: a Hitachi 310 excavator that has been used for 7000 hours still gives an alarm when the hydraulic oil temperature is high, and the excavator water temperature is not high. The hydraulic oil of the excavator is replaced.
Fault analysis:
1. Generally, it is necessary to check whether the excavator has high water temperature first? In the above fault phenomena, it is mentioned that the water temperature of the excavator is not high. It is recommended to see how the oil radiator is ventilated first?
2. Secondly, is it hot to touch the hydraulic oil radiator? Touch the oil cylinder again and compare it. If it is hot, it may be the fault of the hydraulic oil temperature sensor or the false alarm of the circuit fault that causes the high hydraulic oil temperature alarm of the excavator.
3. Check whether the middle between the excavator water tank and the hydraulic oil tank is blocked?
4. Excessive wear of excavator valve core may cause internal leakage, which is easy to cause high hydraulic oil temperature of excavator.
5. Using different grades of hydraulic oil will also cause high hydraulic oil temperature of excavator.
6. When the hydraulic oil flow in the cooling system is small, the Hitachi zw310 hydraulic oil temperature high alarm fault may occur.
7. Check the check valve of the oil return tank, and replace it with a new one if necessary.
8. The oil should be changed. That is to say, the internal friction of the power oil is too large, and the temperature rises faster than the heat dissipation speed.
9. Compare whether the temperature of the radiator and the oil cylinder is close, and then check whether the oil temperature sensor is broken.
Field fault inspection:
The field fault inspection of the excavator found that the middle between the excavator water tank and the hydraulic oil tank was blocked. After opening, the hydraulic oil temperature of the excavator returned to normal and no alarm was given.
