Why do you need a pump in the cooling system? It is also known in motoring circles as car pump, or engine water pump. Why is this part needed, how does it work, how is it arranged and how long does it last?
In continuation of the study of our machines with you, we will now consider this unit, without which the functioning of the cooling circuit under the hood of a car will be extremely complicated.
What is this detail for? To answer this question, it is necessary to recall once again the structure of the cooling system. In short, its main elements are: an engine cooling jacket, a radiator, a thermostat, our today's hero a pump, an expansion tank and all sorts of tubes and pipes through which liquid runs (antifreeze or antifreeze).
One of the conditions under which the engine can be cooled down qualitatively is constant circulation in the system - the antifreeze heated when passing through the power unit must enter the radiator, where it will cool, and then again into the engine.
It is for this work that the car pump is responsible - it drives fluid through the veins of the engine cooling system. Needless to say, the failure of this pump jeopardizes performance power unit in general, because, without cooling down, it will simply boil and stall.
Car pump: everything is simple inside
By itself, the motor water pump is quite simple. Let's take, for example, domestic auto industry, where pumps have a very similar design, regardless of brand and model. Typically, this assembly consists of the following parts:
- frame;
- impeller;
- drive pulley;
- stuffing box;
- bearings.
In case special form shaft is installed main element. On the one hand, a drive pulley is fixed on the shaft, which is in contact with the timing belt and receives rotational energy from it, and on the other hand, it has an impeller that circulates antifreeze through the system.
The gland deserves special attention. Its task is to prevent the leakage of coolant into the cavity where the bearings are located. Since the stuffing box has a tendency to wear out, sooner or later the antifreeze gets to the bearings and finds a way out of the pump, and we will talk about this later ...
Pump failure: what promises and what to do?
As you have probably noticed, the car pump is very simple mechanism, without any tricky engineering solutions and tricks. However, it can also break.
Mainly, water pump malfunctions are associated with the very ill-fated oil seal, which can leak and leak. The antifreeze that has escaped into the wild erodes the grease of the bearings, flows out of the system, which means that something needs to be done with the pomp. In addition to the leak, which up to a certain point you can ignore, there are a number of characteristic breakdowns this node. There are few of them:
- impeller failure - in this case, the pump simply ceases to perform its direct function and the coolant does not circulate through the system or circulates very poorly. Consequences - constant overheating of the car engine;
- jamming of the shaft bearings - this problem can also manifest itself as a result of washing the bearings with coolant. It does not bode well, the pump stops pumping antifreeze, the motor overheats;
- loosening of the impeller on the shaft, deterioration of the density of the shaft fastening, play - initially such problems can be put up with, but sooner or later they will result in something more serious.
Can the water pump be repaired? Of course, but it is impossible to call such a repair expedient. The fact is that the pump is a so-called consumable, and it is recommended to change it every 60 thousand kilometers (or every 48 months). As a rule, the replacement of the assembly takes place along with the replacement of the timing belt.
Thus, our dear readers, we have examined what a car pump is, its device and operation features. We are glad that you are studying the device of cars with us, do not comment and read our blog!
Gives off 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. For this in ICE designs a cooling system, also known as SOD, is provided. 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 article today.
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 built 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 environment(through the radiator, which is in front of the motor).
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.
Where is?
What is a pump, we already know. This is a pump designed for forced circulation 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 cooling jacket itself.
Device
The design of this element contains the following details:
- Frame.
- Gear.
- Impeller.
- Bearings and seals.
We briefly describe each of the above elements below.
Frame
It is the main part of the pump. no need to explain. It is a "bridgehead" for the placement of all constituent parts water pump. The exception is the pulley and the impeller itself. They are on 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 housing and the cylinder block.
It is disposable and cannot be reinstalled when removed. There is also a drain hole in the water pump housing. It prevents the accumulation of moisture and antifreeze at the bearing location.
Oil seals, axles, bearings
Inside the pump is a steel axle. Two bearings are installed on the latter, which provide rotation. Usually the axle is made of high strength steel. And the bearings themselves 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 element for?
It serves to seal the coolant with bearings. It is unacceptable for antifreeze to be in contact with these elements. Otherwise, they will collapse. The stuffing box is rubber element, which is installed on the impeller side of the water pump.
Pulley
The pulley is also referred to as the "gear". Serves given element for taking efforts from the gear wheel can be found on machines with engines, where the gas distribution mechanism has a chain drive.
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.
Impeller
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 pumps on cars are made of aluminum, motorists say.
Principle of operation
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 crankshaft. 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. How more 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 air temperature in the cabin in winter.
Why put an additional pump on the car?
On the forums you can find a lot of topics related to the refinement of the engine cooling system. Especially it concerns domestic cars And budget foreign cars(For example, " Daewoo Nexia"). Why is it installed additional pump by car? This is done in order to increase the coefficient useful action stoves on idling engine. Since the impeller rotates at the same frequency as crankshaft, on Idling its turnover will be minimal. Accordingly, when the machine is standing, the operation of the stove will be inefficient.
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 idle.
Where is the auxiliary pump installed? It can be installed in several places:
- On a stud next to the battery.
- On the fastening of the standard noise insulation on the engine shield.
- On a stud near the washer reservoir.
As a pump, you can take a 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. On this installation additional pump completed.
So, we found out what a pump is in a car.
For the operation of the liquid cooling system of the engine, it is necessary to ensure constant circulation of the coolant. This problem is solved with the help of a water pump or pump - everything about these units, their types, design and operation, as well as their right choice, repair and replacement, read the article.
What is a water pump?
(liquid pump, pump) - a component of the system liquid cooling engines internal combustion; circulation pump, which provides forced circulation of the coolant along the circuits of the system.
The vast majority of modern automobile, tractor and other engines have fluid system cooling - in such a system, water or antifreeze acts as a coolant that provides heat removal from the most heated parts of the power unit. The greatest efficiency of the system is achieved with forced circulation of the coolant - it is for this purpose that circulating water pumps (pumps) are used. Such a pump is installed on the engine and provides a constant circulation of fluid through all circuits of the cooling system.
The water pump is playing important role in the operation of the power unit, failure of the pump in a matter of minutes leads to overheating of the engine and can cause serious damage. Therefore, in case of malfunctions, the pump must be repaired or replaced, and in order to make right choice, it is necessary to understand existing types pumps, their design and principle of operation.
Types and design of water pumps
All modern automotive water pumps are centrifugal type pumps; they pump coolant into the system using a rotating multi-blade wheel (impeller). In such a pump, the impeller is located in a closed cavity with two nozzles: the supply pipe above the center of the impeller and the discharge pipe at the periphery. The coolant enters the middle part of the impeller and is thrown by its blades to the periphery, acquires acceleration and is fed through the discharge pipe into the engine water jacket. So between the inlet and discharge pipes of the pump, a pressure difference is created, which ensures the circulation of the coolant through the system.
Typically, the pump is integrated into the cooling system between the radiator outlet and the engine water jacket inlet. That is, the liquid already cooled in the radiator passes through the pump, due to which the heat load on the unit is reduced and its service life is extended.
Water pump design general case simple. The basis of the unit is a cast housing with pipes (supply and discharge), inside which the impeller is located on the shaft. The impeller shaft is held by one or two bearings in the front wall of the housing, the entire structure is sealed with a self-compressing stuffing box that prevents the coolant from penetrating into the bearing and leaking from the pump housing. The stuffing box has a spring, due to which it is always pressed against the pump housing and provides the necessary degree of tightness. Also, a water deflector can be located inside, preventing water from entering the bearings from the inside. Outside, on the impeller shaft, there is a pump drive pulley hub, on which a fan can also be mounted. On the pulley or on the shaft on the side of the front wall of the pump housing, a dust deflector can be located to prevent dust from entering the bearing.
The pumps that exist today differ in the design of the impeller and housing, the method of installation on the engine, the type of drive, and the presence / absence of a radiator cooling fan drive.
There are two main types of impellers used in pumps:
- Disk - the impeller is structurally made in the form of a flat disk, on one surface of which straight or spiral blades are located;
- Annular - the impeller is made in the form of two disks, between which there are straight or spiral blades.
The most widely used are disc impellers with blades various types. Annular impellers are used less frequently due to their more complex design and high weight. Disc impellers can be cast and stamped, annular impellers can be cast and welded (assembled from separate components).
According to the design of the body and the method of installation on the engine liquid pumps there are:
- Integrated into the engine block;
- Case (autonomous).
Pumps of the first type have a housing open from the side of the impeller - the second part of the housing is a cavity in the engine block. Such a pump is mounted directly on the engine (through a gasket on a specially treated mating surface), it takes up little space and requires a minimum number of connections, since the discharge pipe is usually integrated into the housing and block. It is the pumps integrated into the engine block that have received today most widespread.
Pumps of the second type are made in the form of autonomous units, which are connected to the cooling system by pipes. These pumps are also installed on the engine block (on the mating surface or on separate brackets), but they take up more space than the first type of pumps. Otherwise, cased and integrated pumps do not have fundamental differences.
Water pumps can have two main types of drive:
- Timing belt/chain;
- Auxiliary drive belt.
In the first case, the pump is installed toothed pulley(For toothed belt) or an asterisk (for a chain), in the second case, a pulley is used for a conventional V-belt or V-ribbed belt. Today, all types of drives are used, but pumps driven by a timing belt and poly-V-belt are most widely used. On early engines(especially diesel ones) are still in use V-belt drives with single, twin, triple and quadruple belts.
Finally, the water pump drive pulley can be used to install a cooling fan. The fan can be mounted on a pulley directly (rigidly) or through a viscous coupling, in the first case, the fan runs constantly (since the pump has permanent drive), in the second case the fan is switched on only in a certain temperature range.
Issues of selection, repair and replacement of water pumps
It has a limited resource, which rarely exceeds 80-90 thousand kilometers, so this unit must be changed periodically. To replace, you must choose a pump of the same type and model that was previously installed on the engine, otherwise the unit simply will not fall into place or will not work correctly. It is allowed to install analogues, however, this is far from possible for all cars.
On many modern engines with pump drive timing belt the replacement of this unit is carried out simultaneously with the replacement of the belt and its rollers during regulated maintenance. This is done in order to minimize interference with the operation of the gas distribution mechanism drive - all parts change at once, and the system works normally throughout service interval. For such engines, complete repair kits- timing belt, its rollers, water pump, seals and fasteners.
When buying a new water pump, you must also purchase a gasket - usually it comes with a kit, although in some cases seals can be found separately. Block-integrated pumps require one gasket, casing pumps may require multiple gaskets for each mating surface.
If the pump has not worked out its resource, but there are malfunctions in it (leaks, breakage or deformation of the impeller, bearing wear, etc.), repairs are allowed. Most common problem- wear of the self-clamping gland and leakage of coolant through it. This malfunction is eliminated by replacing the oil seal assembly; as a rule, it is impossible to repair this part. If the casing or impeller breaks, it is easier to replace the pump with a new one.
With the right choice and replacement of the water pump, the engine cooling system will work flawlessly in all operating conditions.
In the engine cooling system, the rotation of the water pump impeller circulates antifreeze in the small and large circuits. Pump malfunctions can not only lead to, but also to a broken timing belt and the subsequent one. Consider the pump device, symptoms and reasons why a pump needs to be replaced.
Malfunction symptoms
- Noise from the pump when the engine is running. extraneous sound appears due to bearing wear. The cooling system pump is recommended to be changed after one or every replacement of the timing kit. If service intervals are neglected, wear appears on the rolling elements, inner and outer races, which leads to noise and whistling. Often the cause of accelerated wear is antifreeze, which, due to leaks in the stuffing box, rubber cuff, gets into rubbing pairs.
- . Like the pump bearing, the oil seal and rubber seal have a limited resource. The appearance of play due to wear of the bearing will greatly approximate the leakage of the stuffing box.
- Misalignment in relation to the timing gears, rollers (the pump becomes skewed). Uneven tension distribution leads to accelerated wear of not only the bearing, but also the oil seal. Wrong installation or a factory defect, in which the pulley rotates skewed, leads to accelerated wear of the loaded part of the belt. Such a defect, even with small runs, can cause the timing belt to break and the valves to meet the pistons.
- Engine overheating. When the impeller blades break off, the pump performance decreases, as a result of which a smaller amount of coolant passes through the small circulation circuit.
Often a decrease in performance is noticed after using a sealant to fix a radiator leak. The filled mixture clogs the channels of the cooling system, sticks to the pump impeller.
If the coolant has not blocked the coolant drain channel in the housing, then filling the sealant will not lead to a malfunction of the water pump. But you can't do without removing the pump and flushing the system. 
How to check the coolant pump?
By checking the pump without removing it from the engine, we can only indirectly evaluate its performance. With a decrease in the volume of pumped coolant, it starts. But before removing the water pump to inspect the impeller, we recommend that you check the thermostat, and also make sure that there is no air lock in the cooling system.
After removal, pay attention not only to the integrity of the blades and the landing site of the impeller on drive shaft, but also on the shape of the blades. For example, for many years of production, impellers were installed on the VAZ 2121, differing in the diameter of the pump wheel, the number and profile of the blades. Installing a less efficient pump on a more heat-loaded engine modification will lead to more frequent switching on of the cooling fan and an increased risk of overheating.
Be sure to inspect the engine block in the place where the housing fits and the pump itself. Fogging, a slight coolant drip from the drain hole does not mean that the pump should be changed. If a significant leak is found, try to pinpoint the exact location of the leak. If the leak is only in the place where the housing is adjacent to the engine block, most likely, the malfunction can be eliminated without replacing the pump. It will be enough to apply sealant and install a new gasket. 
Timing belt break risk
The danger of misalignment of the toothed pulley of the water pump is that there is no obvious signs malfunctions. First of all, you need to pay attention to the timing belt. If it leads to any of the sides, uneven production is observed, it is necessary to check the pump and rollers. The cause of the misalignment may be a factory defect, bearing wear, or an uneven fit of the housing to the engine block (dirty, rusty mating surfaces). Sometimes a malfunction begins to manifest itself after an accident, when body elements or attachments hit the pump pulley.
If misalignment is detected, the defective pump must be replaced as soon as possible. Also, do not hesitate to eliminate noise, whistle from the water pump. With critical wear, the bearing can collapse, thereby blocking the toothed pulley. Jamming the pump is guaranteed to lead to. If, on your car, when the pistons meet the valves when they break, then the elimination of the consequences of the malfunction will result in a rather large amount.
Bearing check
The easiest way is to check the pump, the pulley of which is in accessible place and rotated by a drive belt. It is enough to take the pulley with your hand and shake it in different sides(video verification). In the event of a malfunction, you will feel a large backlash. To determine that the noise, whistle during engine operation comes from the cooling system pump, remove drive belt and spin the pulley by hand. A worn bearing with washed out grease will rotate with noticeable noise, rolls.
Checking the pump, the pulley that is rotated by the timing belt, is somewhat more difficult. Overcoming the force of the belt tension, you can try to shake the gear in different directions. But for a full check and assessment of the smoothness of rotation, the timing belt will still have to be loosened.
The main cause of breakdowns
In the event of a leak in the oil seal or rubber seal, the coolant flushes out the grease from the bearings. The problem will be exacerbated many times if cheap antifreeze or water is used instead of high-quality. The absence of anti-corrosion additives and minimal lubricity will “kill” the pump bearing very quickly.
But much more important is the use of high-quality antifreeze for long term gland service. At the point of contact with drive shaft rubber seals must be lubricated, which does not happen when using aggressive antifreeze, water.
To determine signs of a bad water pump you need to understand what it is and how it works. In fact, everything is quite simple. To cool the engine on hot summer days, it is necessary that the coolant flow constantly circulates in the system, giving off excess heat to the radiator. The pump or water pump is responsible for maintaining a constant flow of coolant in the car. When it works properly, the cooling system maintains the optimum temperature, and the machine works without interruptions and breakdowns. When water pump for car wears out or fails - this in some situations leads to serious malfunctions engine.
Signs of a malfunctioning car pump
When invented water cooling for the engine, many experts believed that the circulation of coolant to remove heat from the cylinder block is as important as engine oil for the motor. So far, fundamental new system cooling system has not been developed, but work is constantly being done to increase the efficiency of the existing cooling system.
At the moment, the water pump is the key to the operation of the entire system. It is an impeller and is usually hidden under protective cover timing belt on the side of the engine. The pump is put into operation through a belt drive from the engine crankshaft. Vanes inside the pump force coolant into the channels of the engine block, and then it flows to the cooling radiator, which reduces its temperature.
Water pumps usually have increased resource work and do not break abruptly. First, there will be several signs that indicate wear, so it is necessary to pay attention to these features in advance. Here are some signs of pump wear.
Coolant leak
The design of the water pump uses sealing gaskets, which maintain the tightness of the system and maintain a certain pressure. Over time, these gaskets wear out, dry out, crack, or break. When this happens, coolant leaks on the road will be visible under the car in the engine area. More often such car water pump problems can be eliminated and the node restored before it finally fails.
The water pump pulley is loose and makes a whining sound
From time to time, a high-pitched sound is heard that comes from engine compartment. This is usually caused by a loose or misaligned drive belt, which creates a hum or ringing sound. A loose drive belt can be caused by worn pump bearings. As soon as the bearings fail inward, the pump is no longer repairable and must be replaced.
Advice. If you notice a loud whining noise from under the hood that increases as you accelerate, get your pump repaired as soon as possible.
Causes of burnt cylinder head gasket
When the pump completely fails, it will not be able to pump coolant flow to the cylinder block. This will cause the engine to overheat and cause further damage, cracked head, burnt head gasket or pistons. If you notice that the engine temperature regularly exceeds the optimum value, then most likely the problem is with the water pump.
Steam coming from the radiator
When you notice steam from under the hood of a car, stop immediately - this is a sign of engine overheating. As mentioned above, the engine supports constant temperature when the water pump runs smoothly and uniform circulation of fluid through the radiator is ensured. When the temperature rises sharply, the liquid turns into steam, which exits the valve expansion tank or radiator. In this case, you can not move by car and it is better to call a tow truck. This saves money in the short and long term and is less expensive than replacing the entire engine.
