Symptoms of engine water pump failure
1. Unstable idle speed: pump failure will increase the rotation resistance of the pump. Because the water pump is connected with the timing belt, the increase of the rotation resistance of the water pump will directly affect the rotation of the engine. When idling, the speed jumps after starting, which is more obvious in winter, and even causes flameout.
2. There will be noise in the engine: this kind of sound is a rotating friction sound, which is similar to "囎囎囎". This kind of sound can be accelerated with the rotation of the engine, and the volume will also change accordingly. This kind of noise will generally become more and more obvious with the aggravation of the fault. An experienced mechanic should be able to hear it. But sometimes, it may be because the replacement of the water pump is too complicated and nothing is said, resulting in many problems.
3, cooling system failure: This is a series of phenomena, all related to the water pump, but not necessarily how complicated the problem is.
1) Hot air is not hot: this fault is the most easily overlooked phenomenon of poor cooling water flow. After the engine water temperature rises in winter, the hot air can't be blown out, and inexperienced people even think that the car is not working, so it's time to change. In fact, changing a small water pump can completely solve the problem.
2) The engine water temperature is unstable: the pointer of the engine water temperature fluctuates within a certain range. The reason is that due to insufficient circulation and inconsistent water temperature in small circulation, on the one hand, the opening temperature of the thermostat rises, and on the other hand, after the high-temperature water flows out, the low-temperature water quickly flows to the thermostat, which makes the thermostat close quickly. Under normal circumstances, after the engine is warmed up, the water temperature will remain at a relatively constant level, about 93℃.
3) Reduced cooling water, poor circulation and high engine temperature: at this time, the water pump has been seriously damaged. If you continue to drive, it will directly lead to increased engine damage. The following is the maintenance and diagnosis process of an owner's engine water pump. At first, he noticed that the radiator fan was spinning at high speed and making a lot of noise. Because running at high speed can cool down, I didn't pay much attention to the problem of water temperature. As a result, I was lucky to run 2500 kilometers without an accident and got home safely. Now that I think about it, I'm a little scared. It was really stupid and bold at that time. After coming back, I ran a normal road and found that the problems of engine water temperature and noise were all manifested. High temperature often occurs, the radiator fan rotates at high speed, and it is not hot to touch the radiator after parking. At first, I thought of the thermostat, but it didn't solve the problem after replacement. I checked the air bleeding method of the cooling system online, which can only solve the problem temporarily. Both trips to and from work need to be inflated and deflated, but the problem has not been fundamentally solved. I checked the cooling system, but I couldn't find the leak. I still don't know the cause of the failure, so I can only replace the water pump. As a result, the above problems disappeared at once, except that the engine water pump was broken.
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