Causes of excessively high water temperature in MTU diesel generator set

Today, I would like to share with you "the reason for the excessively high water temperature of the diesel generator set". Let's have a look at it together.

1, the pump lost the effect of pumping water: in the cold weather, the pump body did not have a small amount of remaining cooling water, overnight that may make the water between the impeller and the inner wall of the pump body ice expansion, resulting in the impeller can not rotate. After the diesel engine starts to run, there is no cooling water circulation in the cooling channel, so that the body temperature rises quickly, the water tank "boiling ". In addition, the pin of the fixed impeller is broken or loosened, the pump shaft rotates and the impeller does not move, the pump will stop pumping water, cooling water does not circulate, resulting in high water temperature.

2. Insufficient water in the cooling system: before the diesel engine starts, the water tank does not add enough cooling water, or the cooling system leaks, the water pump is insufficient, or the water channel, the heat pipe is blocked by scale and dirt, and other reasons will cause insufficient cooling water.

3. The fan belt slips, breaks off, or the blades in the fan are distorted: in this case, the fan belt is too loose and easy to slip, which reduces the speed of the pump and causes the cooling 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 clearance between the piston ring incision is too small, the piston connecting rod group is not installed properly, and the cylinder liner is poorly lubricated, which will cause the friction between the piston group and the cylinder liner to be intensified, the working temperature to rise, and the temperature of the cooling water to be too high.

5, thermostat failure: such as thermostat rupture failure, when the water temperature is higher than 70℃, the valve can not open or open height is not enough, resulting in cooling water can not be through the radiator for large circulation, resulting in high water temperature.

6, the oil supply time is too late: the oil supply is too late, the diesel combustion is not complete, resulting in overheating of the diesel engine, the bottom surface temperature of the cylinder head rises, resulting in high water temperature.

Fault check judgment:

A. Check the water pump: grasp the outlet pipe connected to the radiator with the cylinder head by hand, and increase from idle speed to high speed. If the water flow is felt to increase, it indicates that the water pump is normal. If the pin is broken or loose, the pump shaft rotates and the impeller does not move, the pump will stop pumping water, at this time should replace the pump impeller pin; If the pump impeller is reversed, the pump can not pump water.

B. Check cooling water: before starting the diesel engine, check whether the cooling water is enough, and check whether the water pipe and heat dissipation pipe are blocked.

C, check the fan belt: if the belt is too loose should be adjusted; If the belt is worn too much or broken, it should be replaced in time; If there are two belts and only one of them is damaged, two new belts must be replaced. It is not allowed to match the old with the new. Otherwise, the service life of the new belt will be greatly shortened.

D. Check the clearance between cylinder liner and piston: check whether the clearance of piston ring incision is too small, and whether the lubricating oil of cylinder liner is enough. If it does not meet the requirements, the relevant parts need to be replaced.

E. Check the thermostat: for the engine equipped with the thermostat, if there is a large stream of water flowing out of the inlet pipe of the upper water chamber of the water tank, it indicates that the thermostat valve is not closed strictly or is damaged; If the water temperature is much higher than 70 ° C and there is no water flow out of the inlet pipe of the upper water chamber or no large stream of water flow out, it indicates that the thermostat is damaged or weakened.

F. Check whether the oil supply advance Angle is normal: Note: If the oil injection advance Angle is not normal, the diesel exhaust smoke color will be abnormal.

Jiangsu Meao Power Technology Co., Ltd. is an important manufacturer of diesel generators. The company mainly manufactures and sells diesel generator sets with power of 3-3000kW, mobile power station of 24-600kW, Marine emergency diesel generator set of 24-800kW, gas generator set, heavy oil generator set and all kinds of imported series, special series (trailer, static speaker, mobile lighthouse, container, etc.) diesel generator At the same time, we are engaged in generator set maintenance and after-sale service of generator set accessories.