First, the influence of cooling water flow: insufficient cooling water. Thermostat hairpin, malfunction. The pump is damaged or the conveyor belt slips, causing the pump to work badly.
Two, the influence of heat dissipation ability on water temperature: radiator, cylinder, cylinder head water jacket deposit too much scale, reduce the cooling water cooling function. And too much scale deposition in the water jacket will also cause the circulation pipeline section to reduce, so that the amount of water participating in the cooling cycle is reduced, thereby reducing the absorption of cylinder block, cylinder head heat capacity resulting in high temperature of cooling water. The radiator capacity is too small, the heat dissipation area is too small, affecting the heat dissipation effect, resulting in high water temperature.
Three, the influence of engine load on water temperature. The diesel engine is not working well. Overload for a long time at low speed, so that the diesel engine overheating, causing excessive water temperature.
Resources:
The advantages of diesel engines are large torque and good economic performance. The working process of a diesel engine has many similarities with that of a gasoline engine. Each working cycle also goes through four strokes: intake, compression, power and exhaust. But because diesel fuel is diesel fuel, its viscosity is bigger than gasoline, not easy to evaporate, and its spontaneous combustion temperature is lower than gasoline, therefore, the formation and ignition of combustible mixture are different from gasoline engine.
The main difference is that the mixture in the cylinder of a diesel engine is compressed-fired rather than ignited. When a diesel engine works, air enters the cylinder. When the air in the cylinder is compressed to the end point, the temperature can reach 500-700℃ and the pressure can reach 40-50 atmospheres.
When the piston is near the top dead center, the injector nozzle of the oil supply system injects fuel into the cylinder combustion chamber at extremely high pressure in a very short period of time. The diesel oil forms fine oil particles, which are mixed with the air of high pressure and high temperature. The combustible mixture burns by itself, and the explosive force is generated by violent expansion, which pushes the piston to do work downward. The pressure is up to 60-100 atmospheres and the torque is very high, so the diesel engine is widely used in large diesel equipment.
The characteristics of the traditional diesel engine: thermal efficiency and economy is better, the diesel engine uses compressed air to improve the air temperature, so that the air temperature exceeds the spontaneous combustion point of diesel fuel, then injected into the diesel fuel, diesel spray and air mix at the same time their ignition combustion. As a result, diesel engines do not need an ignition system.
At the same time, the diesel fuel supply system is relatively simple, so the reliability of diesel engines is better than that of gasoline engines. The diesel engine has a high compression ratio because it is not restricted by deflagration and the need for diesel spontaneous combustion. Thermal efficiency and economy are better than gasoline engine, at the same time in the case of the same power, diesel engine torque is large, the maximum power speed is low, suitable for the use of trucks.
Post time: Jun-01-2021