Drivers know that sometimes, especially in summer, when the water tank of internal combustion forklift will be very hot, they must stop, which will affect the work of forklift and damage parts in serious cases. What are the reasons for the high temperature of forklift water tank? How to solve it? Dalian forklift tells you:
Reasons for high water temperature of forklift truck
There are many reasons for the high water temperature: temperature control switch, pump, sub fan, rusted water pipe, poor return water and other factors will cause this phenomenon. The water temperature of the engine is mainly related to whether the thermostat works normally, whether the water pump can establish sufficient pressure and whether the cooling fan can reach the standard speed. How to check if the forklift water temperature is abnormal? The cooling system is generally composed of cooling fan, radiator, thermostat and other components. The cooling fan is often driven directly by the engine, and the fan speed is consistent with the engine speed. The control of cooling water temperature mainly depends on thermostat.
Principle of thermostat
The thermostat, also known as the thermostat, is used to automatically adjust the amount of water entering the radiator according to the temperature of the cooling water and change the circulating range of water, so as to adjust the heat dissipation capacity of the cooling system and ensure that the engine works within the appropriate temperature range. The thermostat must be kept in good technical condition, otherwise it will seriously affect the normal operation of the engine. If the main valve of thermostat is opened too late, the engine will overheat; If the main valve is opened too early, the engine preheating time will be prolonged and the engine temperature will be too low. At this time, it can be judged whether the thermostat is in good working condition. When the engine starts cold running, if there is still cooling water flowing out of the water inlet pipe of the upper water chamber of the water tank, it indicates that the main valve of the thermostat cannot be closed; When the engine cooling water temperature exceeds 70 ℃, and there is no cooling water flowing out of the water inlet pipe of the upper water chamber of the water tank, it indicates that the main valve of the thermostat cannot be opened normally, and it needs to be repaired.
The thermostat can be checked on the vehicle as follows:
1、 Inspection after starting the engine: open the radiator water filler cap. If the cooling level in the radiator is static, it indicates that the thermostat works normally; otherwise, it indicates that the thermostat works abnormally.
2、 This is because when the water temperature is lower than 70 ℃, the expansion cylinder of the thermostat is in the contraction state and the main valve is closed; When the water temperature is higher than 80 ℃, the expansion cylinder expands, the main valve gradually opens, and the circulating water in the radiator begins to flow.
3、 When the water temperature gauge indicates that it is below 70 ℃, if there is water flowing at the radiator inlet pipe and the water temperature is warm, the main valve of the thermometer is not closed tightly, resulting in premature large circulation of cooling water.
4、 Inspection after the water temperature rises: at the initial stage of engine operation, the water temperature is thousands of and fast; When the water temperature gauge indicates 80 and the heating rate slows down, it indicates that the thermostat works normally. On the contrary, if the water temperature rises rapidly all the time, when the internal pressure reaches a certain degree, the boiling water suddenly overflows, which indicates that the main valve is stuck and suddenly opens.
5、 When the water temperature gauge indicates 70 ℃ - 80 ℃, open the radiator cap and radiator drain switch, and feel the water temperature by hand. If it is hot, the thermostat works normally; If the water temperature at the water inlet of the radiator is low, and there is no water flowing out of the water inlet pipe of the radiator upper water chamber or there is little water, it indicates that the main valve of the thermostat cannot be opened.
The water pump is the driving force for the continuous circulation of cooling water in the cooling system. The factors affecting the water pump are the impeller and belt. If the impeller is loose, the cooling water cannot be circulated, resulting in the damage of the water pump. If the belt is too large, the water temperature will be too high, and if it is too small, the water pump bearing and generator bearing will be damaged.
Detection of fan air volume: a thin paper can be placed in front of the radiator. When the engine is running, if the paper can be blown away, it indicates that the air volume is sufficient. This is different from the inward suction of the car fan of the front engine. The blades shall not be installed reversely, and the fan discharge shield shall be complete and effective.
In terms of radiator, the chassis of the forklift is low, and the radiator is placed at the rear of the vehicle. Dust is easy to accumulate on the surface of the radiator. If it is not cleaned in time, it will seriously affect the heat dissipation effect. It is strictly forbidden to use "hard water" in the cooling water to prevent scale in the radiator, resulting in insufficient addition of cooling water.
Dalian forklift reminds you that when driving a forklift, you need to pay more attention to observation, take precautions and prevent greater faults.
