The temperature of the bulldozer hydraulic system is generally within the range of 35 to 60 ℃, and the highest temperature should not exceed 80 ℃. Under normal oil temperature, all aspects of hydraulic oil perform well. If the oil temperature is too low or too high, its performance will be significantly reduced. If it is too high, the viscosity will be reduced, the oil film will be easily destroyed, the lubrication performance will be deteriorated, and the hydraulic components will be worn faster; as the viscosity is reduced, the leakage will increase, and the working efficiency of the hydraulic components will also decrease; too high oil temperature will also accelerate the hydraulic pressure The oil has deteriorated and the rubber seals have aged. So what are the reasons for the high oil temperature of the hydraulic system:

　　1: Poor heat dissipation from the cooler.

　　2: The internal leakage is serious.

　　3: The limit pressure of the system safety valve is too high or too low.

　　4: Continuous overload work or high ambient temperature;

　　5: Misuse of hydraulic oil with too high viscosity.

　　6: The hydraulic components wear out and generate heat locally.

　　7: The oil pump sucks air badly.

　　The hydraulic oil temperature is too high, you can use the following methods to gradually troubleshoot

　　1: Clean the radiator.

　　2: Repair or replace seals.

　　3: Re-adjust the safety valve.

　　4: Shut down.

　　5: Change to standard hydraulic oil.

　　6: Replace or repair.

　　7: Diagnose the suction failure, prevent the oil pump from sucking in air and cavitation

　　In addition, the oil temperature is detected by the tactile method, that is, the finger touches the hydraulic components such as the oil pump, the overflow valve, the flow valve, the oil cylinder, the oil motor, and the hydraulic oil to judge the heating.

　　1: If the finger feels colder, it is about 5-10 ℃.

　　2: It is about 15 ～ 20 ℃ if you wait for the finger to feel cold or warm.

　　3: If the finger feels warm to the touch, it is about 20 to 35 ℃.

　　4: If the finger feels hot and hot to the touch, but it can tolerate about 40 ~ 50 ℃.

　　5: If the fingers feel hot to the touch, they can only endure 2～3 s, about 50～60℃.

　　6: If the finger feels hot to the touch but retracts like lightning, it is about 70°C.