1. Fault phenomenon The temperature of the cooling water is too high. The pointer of the water temperature gauge often refers to above 100 °C, and it is accompanied by the phenomenon of "opening" of the radiator. However, the single-cylinder diesel engine such as S195 is a self-flow evaporative cooling, and water boiling is a normal phenomenon.
2. Cause of failure 1 The pump loses its pumping effect. When the weather is cold, the cooling water left in the pump body is not exhausted. The water between the impeller and the inner wall of the pump body can be frozen overnight, so that the impeller cannot rotate. After the diesel engine is started, there is no cooling water circulation in the cooling water channel, so that the temperature of the body rises quickly and the water tank is “opened”. In addition, the pin of the fixed impeller is broken or loosened, the water pump shaft rotates and the impeller does not move, the water pump stops pumping water, the cooling water does not circulate, and the water temperature is too high. 2 The amount of water in the cooling system is insufficient. Before the diesel engine starts, there is no sufficient cooling water in the water tank, or the cooling system leaks, the water supply of the pump is insufficient, or the water pipe and the heat pipe are blocked by scale and dirt, which will cause insufficient cooling water. 3 The fan belt is slipping, breaking off, or the blades in the fan are twisted. In this case, the fan belt is too loose and slippery, causing the speed of the water pump to decrease, causing the cooling system water temperature to be too high. 4 The clearance between the cylinder and the piston is too small. The clearance between the cylinder liner and the piston is too small, the gap between the piston ring is too small, the piston rod set is not installed properly, and the cylinder sleeve is poorly lubricated, which will cause the friction between the piston unit and the cylinder liner to increase, causing the working temperature to rise, resulting in the cooling water temperature. high. 5 thermostats failed. If the temperature of the thermostat is broken, when the water temperature is higher than 70 °C, the valve cannot be opened or the opening height is not enough, so that the cooling water cannot be circulated through the radiator and the water temperature is too high. 6 oil supply time is too late. The oil supply is too late, the diesel combustion is not complete, causing the diesel engine to overheat and the temperature of the bottom surface of the cylinder head to rise, resulting in excessive water temperature.