What are the failures of general internal combustion forklifts? How to maintain it? Drivers of internal combustion forklift trucks should learn to understand and judge some simple issues.
What caused the forklift water temperature to be too high? There are many reasons for high water temperature: temperature control switches, pumps, sub-fans, rusty water pipes, poor return water and other factors. The engine water temperature is mainly related to whether the thermostat is working normally, whether the water pump can build enough pressure, and whether the cooling fan can reach the standard speed. How to check if the water temperature of the forklift is abnormal? It is generally composed of cooling fans, radiators, thermostats and other components. The cooling fan is often directly driven by the engine, and the fan speed is consistent with the engine speed. The control of the cooling water temperature mainly relies on the thermostat.
The principle of thermostat:
The thermostat is also called thermostat. Its function is to automatically adjust the amount of water entering the radiator according to the temperature of the cooling water, change the water circulation range to adjust the heat dissipation capacity of the cooling system, and ensure that the engine works within a suitable 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 the thermostat is opened too late, it will cause the engine to overheat; if the main valve is opened too early, the engine warm-up time will be prolonged and the engine temperature will be too low. At this time, it can be judged whether the working condition of the thermostat is in good condition. When the engine starts to run cold, if there is still cooling water flowing out of the water inlet pipe of the water tank, it means that the main valve of the thermostat cannot be closed; When the water temperature exceeds 70 degrees Celsius, and there is no cooling water flowing out of the water inlet pipe of the upper water chamber of the water tank, it means that the main valve of the thermostat cannot be opened normally, and repair is required at this time. The thermostat can be inspected on the car, and the method is as follows:
1. Inspection after engine start: Open the radiator water filler cover. If the cooling level in the radiator is static, it means that the thermostat is working normally, otherwise, it means that the thermostat is working abnormally.
2. This is because when the water temperature is lower than 70℃, the thermostat expansion cylinder is in a contracted 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 starts flow.
3. When the water temperature gauge indicates below 70℃, if there is water flowing at the water inlet pipe of the radiator and the water temperature is warm, the main valve of the thermostat on the meter is not closed tightly, causing the cooling water to circulate prematurely.
4. Check after the water temperature rises: At the beginning of the engine operation, the water temperature reaches thousands of times quickly; when the water temperature gauge indicates 80, the heating rate slows down, which indicates that the thermostat is working normally. On the contrary, if the water temperature has been rising rapidly, when the internal pressure reaches a certain level, the boiling water suddenly overflows, which indicates that the main valve is stuck and suddenly opened.
5. When the water temperature gauge indicates 70℃-80℃, open the radiator cover and the radiator water release switch, and feel the water temperature with your hands. If they are hot, the thermostat is working normally; if the water temperature at the water inlet of the radiator is low and the radiator There is no or very little water flowing out of the inlet pipe of the upper water chamber, indicating 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 the belt. If the impeller is loose, the cooling water cannot circulate, resulting in damage to the pump. If the belt is too large, the water temperature will be too high. If the belt is too small, it will damage the bearings of the water pump and generator.
The detection of the fan air volume can put a thin paper in front of the radiator. When the engine is running, if the paper can be blown away, it means that the air volume is sufficient. This is different from the front-engine car fan sucking inward. The blades cannot be installed backwards, and the fan guard should be fully and effective.
The chassis of the radiator 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" for the cooling water to prevent the generation of scale in the radiator, resulting in insufficient cooling water.
