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What is a pump and why is it needed in a car?

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What is a pump and why is it needed in a car?
What is a pump and why is it needed in a car?

As you know, any internal combustion engine generates a lot of heat. Part of the energy is converted into torque, but do not forget that during operation the motor heats up significantly. Accordingly, he needs a good heat sink. To do this, the design of the internal combustion engine provides for a cooling system, also known as SOD. It includes many pipes, a radiator, a thermostat and various auxiliary elements. But the most basic element is the pump. What is a pump and what does it serve? Read about this and more in our today's article.

Characteristics and purpose

SOD on most cars is a liquid type. Coolant is poured into the system. This is usually antifreeze or antifreeze. How does cooling take place? This process is based on the principle of circulation of cold and hot flows of antifreeze in the system. Moving through the channels of the jacket in the motor block, the liquid takes part of the heat and removes it to the environment(through the radiator at the front of the engine).

best pumps for cars

Why do you need a pump in a car engine? The liquid itself cannot circulate in the system. And since the heating process here is constant and intense, cooling should be as efficient as possible. To this end, engineers have come up with a special pump. It is he who ensures the circulation of cold and hot coolant in the system forcibly. What other functions does the pump perform? Oddly enough, in addition to the above, this pump does not perform any more functions. But the serviceability and durability of the power unit depends on its work. Overheating is critical for the motor, and thanks to the water pump, the motor operates at the optimum temperature.

car pump in the engine

Good to know: the optimum temperature for engine operation is considered to be a threshold of 85-90 degrees. Moreover, not only overheating is harmful to the motor. The engine is also harmed by the so-called underheating (when the sensor needle is in the region of 60-70 degrees Celsius). Along with this, problems with the power unit are possible, including improper mixture formation and increased fuel consumption (since the electronics will try in every possible way to force the engine to heat up).

Where is it?

What is a pump, we already know. This is a pump designed for forced circulation of coolant. And it is located in the engine design itself. To be specific, the pump is located near the engine block, and the impeller is in the shirt itselfcooling.


The design of this element contains the following details:

  • Case.
  • Gear wheel.
  • Impeller.
  • Axis.
  • Bearings and seals.

We will briefly discuss each of the above elements below.


It is the bearing part of the pump. What a corpus is, no need to explain. It is a "bridgehead" for placing all the components of the water pump. The exception is the pulley and the impeller itself. They are on the outside. The pump housing itself is made of aluminium. In order to exclude all kinds of leaks, a gasket is installed at the junction of the body and cylinder block.

what is a pump

It is disposable and cannot be re-installed when removed. There is also a drain hole in the water pump housing. It prevents moisture and antifreeze from accumulating at the bearing location.

Oil seals, axles, bearings

There is a steel axle inside the pump. Two bearings are installed on the latter, which provide rotation. Usually the axle is made of high strength steel. And the bearings themselves are of a closed type. Inside them is a lubricant laid down for the entire period of operation. As a rule, it lasts for a long time. Usually bearings are nursed for 200-250 thousand kilometers. Now about the seals. What is this item for?

why put an additional pump on the car

It serves to seal the coolant with bearings. It is unacceptable thatantifreeze was in contact with these elements. Otherwise, they will collapse. The oil seal is a rubber element that is installed on the side of the water pump impeller.


Pulley is also referred to as "gear". This element serves to receive forces from the crankshaft. The gear wheel can be found on machines with engines where the gas distribution mechanism has a chain drive.

extra pump for car

And on an internal combustion engine with a “belt”, the pulley also ensures the operation of other attachments. This is an air conditioning compressor, hydraulic booster and so on. Unlike chain motors, there is no slippage during operation. Therefore, the presence of teeth on the wheel is not necessary here. This element is bolted rigidly to the axis of the pump.


It is installed on the other side of the axle. The impeller is a disk with wings printed on it (hence the specific name). The part is made of aluminium. But recently, more and more cars come with plastic impellers. The part is rigidly fixed on the pump axis and rotates in proportion to the crankshaft. What is more reliable - plastic or aluminum? Many experts advise choosing a metal impeller. The best car pumps are made of aluminum, motorists say.

Working principle

Most vehicles (including the VAZ-2110) use a centrifugal pump. It is put into operation thanks to a belt drive. The torque to the pump comes from the crankshaftshaft. So, while the engine is running, the pump receives rotation from the pulley to the impeller. Thus, it also begins to rotate, forcing the liquid to circulate through the system. The more the driver gives gas, the more the pump (namely, its impeller) spins up. Due to the pressure, hot antifreeze penetrates the radiator and cools there. And from the latter, in turn, already cold coolant goes into the shirt on the cylinder block. Further, the liquid again absorbs heat and is directed to the radiator. Also, part of it falls on the stove radiator, which is in the cabin. This ensures optimum cabin air temperature in winter.

Why put an additional pump on the car?

On the forums you can find many topics related to the refinement of the engine cooling system. This is especially true for domestic cars and budget foreign cars (for example, the Daewoo Nexia). Why install an additional pump on a car? This is done in order to increase the efficiency of the stove at idle engine speed. Since the impeller rotates at the same frequency as the crankshaft, its idle speed will be minimal. Accordingly, when the machine is stopped, the operation of the stove will be inefficient.

What is an additional pump, few people know. But such a "cunning" has long been practiced on the "BMW" and "Mercedes". The system allows you to quickly drive the fluid in the heater system, providing hot air in the cabin. Will the motor freeze from this? Not at all, experts say. The heater radiator does not have such a huge size at which it would take heat from the internal combustion engine at idlego.

car pump

Where is the additional pump installed? It can be mounted in several places:

  • On a hairpin near the battery.
  • On the fastening of the standard noise insulation on the motor shield.
  • On a hairpin near the washer reservoir.

As a pump, you can take the pump from the GAZelle. Connection is carried out by means of two S-shaped hoses (can be taken from the "eight"). All branch pipes must be tightened with clamps, and power must be connected to the SAUO unit. This completes the installation of the additional pump.

So, we found out what a pump is in a car.

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