1. For the problem that the air passage between the cooling water tank radiator chips is covered by dust and grass clippings, the following measures should be taken:

(1) Change the position of the cooling air inlet. At present, the cooling air of the small and medium-sized wheel tractor engines is sucked from the front end of the tractor by the cooling fan to the radiator of the water tank. During the harvesting operation, the front end of the header is easily sucked onto the water tank heat sink chip by the front windshield of the locomotive due to cutting, conveying dust and grass debris. In order to change this situation, we must try to change the inlet position of the cooling air so that the air inlet is higher than the front cover of the tractor, so that the dust and grass clippings of the header are not easy to enter the radiator of the water tank, delaying the increase of water temperature. .

(2) Set a dust-proof board at the air inlet (about 10 cm in front), the area is larger than the front end area of ​​the tractor casing, and the periphery should be slightly bent backwards. The dust and grass clippings raised at the front end of the header are mostly blocked by the dust shield or directed to the periphery of the air inlet. At the same time, the original windshield net must be replaced with a wire mesh of about 40 mesh, and the wire mesh can be blocked in places where it is possible to enter the wind, so that the dust and grass clippings sucked in will be greatly reduced, and the water temperature rise can be delayed. high.

(3) Add a secondary water tank at the same time as the dust cover, and increase the capacity of the cooling water to delay the heating rate of the cooling water.

(4) Change the placement position of the cooling water tank. Remove the original cooling water tank, design a bracket to place the water tank and the fan to the top of the same vertical plane as the original water tank. The height is not suitable for the operator's line of sight. Connect the engine and the water tank in the original circulation mode, and use the appropriate length. The V-belt is connected to the fan. This method can improve the working conditions of the cooling water tank, not only the dust and grass clippings are not easy to stick to the radiator of the water tank, but also the ventilation conditions are greatly improved. This method also has a good cooling effect.

(5) Under the condition that there is no way, the front cover of the tractor can be temporarily removed, and the engine and the cooling system are directly exposed to the air. This also has a certain heat dissipation effect, but it looks very unsightly and should not be used under normal circumstances.

2. Excessive overload operation is strictly forbidden, and the load control in high temperature season is about 90%, so that the waterproof temperature is too high.

3, the engine should be filled with clean soft water, the operation should always check whether the water tank is short of water and water leakage.

4. Check and adjust the tension of the fan belt according to the requirements of the instruction manual to ensure the fan's proper speed and supply sufficient air volume to cool the water tank or the body.

5. For the engine that has been used for a long time, the cooling system should be thoroughly cleaned to remove scale. When cleaning, first remove the thermostat, then prepare the cleaning solution according to the ratio of 20 kg of water, 1.5 kg of caustic soda, and 0.5 kg of kerosene. After injecting into the water tank, start the engine and run at a fast and slow speed for 5-10 minutes until the water temperature rises. Turn off at 70-80 °C, let stand for 10-12 hours, start the engine again, run at medium speed for 5-10 minutes, then turn off the heat, drain the cleaning solution while hot, add water, and release at medium speed for 4-5 minutes. In order to flush the cooling system, after cleaning two or three times, replace the thermostat and add enough cooling water.

6. Check the working performance of the thermostat. If necessary, remove it (in high temperature weather) to prevent the thermostat from malfunctioning and affect the normal circulation of the cooling water and reduce the cooling function.

7. For pumps with long working hours, check the impeller of the pump and the inner hole of the pump casing, the wear of the pump shaft and the bearing, and the water seal assembly. If the damage is serious, the displacement will be insufficient, which will affect the circulation of the cooling water.

8. Test the sealing performance of the valve for the engine that has been used for a long time, and check and adjust the valve clearance correctly. If the valve seal is not good, it will cause high temperature and high pressure gas to leak, causing the engine temperature to rise. The main reason for poor sealing is that the valve seat is not in good contact with the valve and the spring force is weak. If the valve is not closed, it should be repaired in time.

9. Adjust the fuel supply advance angle accurately to ensure the timing of oil supply. When the fuel injection pump is used for a long time, the parts such as the camshaft, the roller and the follower column are seriously worn, which will cause the oil supply time to be too late, so that the diesel fuel injected into the cylinder cannot be completely burned in time, or the afterburning may occur, causing the engine to overheat. Therefore, it is necessary to check and adjust the fuel supply advance angle in time.

10. Check and adjust the fuel injector so that the injection pressure, atomization and spray cone angle meet the specified requirements. If the atomizer of the injector and the spray cone angle are not good, the fuel and the air will not mix well, resulting in a decrease in the burning speed, prolonging the burning time, and causing the engine temperature to rise.

11, must be considered in the design. Because the combine harvester has a long working time, high ambient temperature, poor ventilation, and slow walking speed, working in such a bad situation, the working capacity of the engine cooling system is particularly important. The cooling capacity should be determined during the design of the engine in high temperature and full load conditions. In order to increase the cooling capacity, it is recommended to consider the following two problems: on the one hand, it is necessary to improve the volumetric efficiency of the fan, improve the transmission capacity of the fan belt, reduce the slip rate, select the optimal ventilation position, and reduce the flow resistance of the cooling air. Increase the amount of air intake; on the other hand, it is necessary to improve the fan blade structure and design the streamlined hood to increase the heat dissipation area and fundamentally improve the cooling capacity.

12. If an air-cooled engine is selected on the combine harvester, it is necessary to consider properly increasing the ventilation capacity and reducing the poor heat dissipation. (Pity silk)