# Tips for Solving the Problem of Hydraulic Forklifts Not Cooling Properly

1. Internal Combustion Engine System Adjust the center distance of the pulleys to achieve proper belt tension, ensuring the driven pulley does not slip or lose rotation. Ensure the pipelines between the internal combustion engine cylinder liners are unobstructed. Replace the thermostat that has already failed. Adjust the ignition timing of the internal combustion engine to ensure normal combustion. Increase the water pump displacement. When the water pump displacement increases, the amount of water flowing through the radiator per unit time will increase, and the heat dissipation capacity will increase accordingly. The water pump displacement depends on the water pump speed, the water pump speed depends on the speed of the driven pulley, and the speed of the driven pulley depends on the diameter of the driving pulley or the driven pulley. Therefore, we always hope to increase the water pump speed. However, if the water pump speed is too fast, the service life of the water pump will be shortened; the water pump sucking air will also reduce the efficiency of the water pump, and the heat dissipation capacity will instead decrease. Therefore, under the condition of ensuring that the water flow velocity in the water pump inlet pipe does not exceed 3 m/s, the diameter of the pulley can be appropriately increased, thereby increasing the water pump displacement. 2. Radiator System Improve welding quality to prevent weld detachment or cold solder joints. Pay attention not to damage the fins during transportation, assembly, and use of the radiator. A tube-and-strip radiator core can also be selected. Practice has proven that this type of radiator core has strong heat dissipation capacity, is simple to manufacture, is lightweight, and has low cost, but its structural rigidity is poor. Increasing the heat dissipation surface area of the radiator will inevitably increase the heat dissipation capacity. Increasing the frontal area of the radiator, reducing the pitch of the fins and tubes along the frontal and thickness directions of the radiator, and thickening the radiator can all increase the heat dissipation surface area. However, the latter measure has little effect. For example, if the thickness of the radiator is increased by 50%, its heat dissipation capacity increases by 15%; when the thickness of the radiator is increased by 100%, its heat dissipation capacity increases by only 20%. According to the formula L=A0/A×ψ (where: L — radiator thickness; A0 — total heat dissipation area of the radiator; A — frontal area of the radiator; ψ — compactness volume coefficient of the radiator), it can be seen that under the condition that the total heat dissipation area of the radiator remains unchanged, increasing the frontal area of the radiator can reduce the radiator thickness, and reducing the radiator thickness will reduce ventilation resistance, increase the air volume passing through the radiator, and greatly improve the heat dissipation capacity. In addition, the distance between the fan and the radiator must also be adjusted. For the cooling systems of different forklifts, the optimal distance between the fan and the radiator is different. Only by finding the optimal distance through testing can the potential and role of the cooling system be fully utilized to achieve the best effect. 3. Fan System Measures such as increasing the fan diameter, increasing the number of blades, increasing the blade installation angle, increasing the width of the blade chord, increasing the maximum peripheral speed of the blades, and using convex blades can all increase the ventilation volume and improve heat dissipation performance. However, the blade installation angle cannot be too large. When it exceeds a certain critical value, the direction of the exhaust air will change with the increase of the blade installation angle. Axial exhaust will gradually decrease, and radial exhaust will gradually increase. Radial exhaust not only fails to cool the radiator, but instead causes secondary heating of the various components of the forklift. At the same time, the fan speed also cannot be too fast, because the power driving the fan is proportional to the cube of the fan speed. If the speed is too fast, the power loss of the internal combustion engine will be too great. The failure of the cooling system to operate normally is the direct cause of excessive forklift temperature. To solve this problem, it is necessary to start from three aspects: the internal combustion engine system, the radiator system, and the fan system. Ensuring the water pump displacement, improving the welding quality of the radiator (preventing weld detachment or cold solder joints), and increasing the working efficiency of the fan are all good methods to effectively solve the problem of abnormal heat dissipation in forklifts.