Installation and structure of automobile water pump.

Installation Position Of Water Pump

1. Installation position of the mechanical water pump
The mechanical water pump is driven by the engine crankshaft through the transmission tape, and its speed is proportional to the engine speed. There are advantages and disadvantages to the way mechanical pumps work. When the engine works under high speed and large load condition, the engine generates more heat, and the high speed of the pump increases the circulation flow of coolant, which can improve the cooling capacity of the engine. When the engine works under low speed and heavy load conditions, such as pulling other vehicles or turning on air conditioning, the low engine speed leads to low pump speed, which reduces the cooling capacity of the engine.
2. Installation position of electric water pump
The electric water pump is controlled by the engine control unit through the current. It is not affected by the engine speed at that time and can work flexibly according to the actual cooling needs of the engine. Because the electric pump consumes very little power of the engine, the fuel consumption of the engine can be reduced by using the electric pump.

Automobile Water Pump Structure Composition

The structure of the automobile water pump is as follows:
The pump used by the automobile engine is a centrifugal pump, which is composed of shell, impeller, bearing, pump shaft, water seal and transmission pulley.

(1) The Shell
The pump housing is made of cast iron or cast aluminum. The cast iron shell has thick wall and large mass. With the improvement of the requirements for lightweight engine, only some large engines of commercial vehicles still use cast iron shell water pump. Many cast-iron housings also have partial channels and thermostat mounting chambers, which further increase the weight of the housings. Most automotive water pumps use cast aluminum shells, and the size of the shells is getting smaller and smaller, many shells no longer have the function of a waterway.
(2) The Impeller
Pump impeller is made of cast iron and other metals or engineering plastics. It adopts backward bending semi-arc, double arc or multi-circle solitary blade. Its leaf shape is consistent with the direction of water flow, and the pump water efficiency is high. Water pump impeller made of cast iron has high quality but high mechanical strength. It is widely used in large engines of commercial vehicles. Plastic impeller is easy to achieve miniaturization and lightweight, and good corrosion resistance, shape processing is easy to control, so more and more automobile engine water pumps use plastic impeller.

Cause Of Water Pump Damage

The reasons for water pump damage are as follows:
1, Rapid Instability:

Pump failure can cause pump rotational resistance to increase. Because the pump is connected with the timing belt, the increase of pump rotation resistance can directly affect the engine rotation. When idling, the performance is the beating of the speed after starting, which is more obvious in winter and can even cause flameout.

2. Engine use trigger:

Engine pump abnormal sound, this sound is rotating friction sound, similar to the sound of chengchang. This sound can be accelerated with the engine rotation, and the volume changes. This noise is generally with the severity of the fault and become more and more obvious. An experienced mechanic should be able to tell. But at a slight moment, perhaps because the replacement of the pump is too complicated, they all said nothing, and the result was a lot of problems.

3. Cooling system failure causes:

This is a series of fault phenomena, such as lack of cooling water, cooling water scale, temperature thermostat does not open and other faults will cause water pump failure damage.

1) Hot air is not hot:
This failure is the most overlooked phenomenon caused by poor cooling water flow. In winter, when the temperature of the engine warms up, the hot wind does not blow out. Inexperienced people even think that the car is not good, it is time to change the car. In fact, change a small water pump can solve the problem completely.
2) Unstable engine water temperature:
The indicator needle of engine water temperature fluctuates in a certain range. The reason is that the water temperature in the small cycle becomes inconsistent due to the lack of circulation. On the one hand, the opening temperature of the thermostat increases; on the other hand, after the high temperature water flows out, the low temperature water quickly flows to the thermostat, making the thermostat quickly shut down. Under normal circumstances, after heating up, the water temperature of the engine will be kept at a relatively constant level, about 93℃.
3) Reduced cooling water, poor circulation and high engine temperature:
By this time, the pump has been relatively serious damage.