Self-replacement of the thermostat on a UAZ Patriot (ZMZ 409).

Method for connecting a thermostat to a UAZ

Cars from the Ulyanovsk Automobile Plant (UAZ) have long been deservedly popular among fans of extreme sports, recreation and more. Ordinary fishermen and hunters also appreciated the UAZ’s ability to overcome off-road conditions. It all started back in 1965, when production of the UAZ 452 car, better known by the popular name UAZ “loaf” or “tablet”, began. At the same time, for the first time in the Soviet press, an image of the UAZ 469 model appeared, the actual production of which began in December 1972.

You can list for a long time the advantages and disadvantages of UAZ cars compared to each other or other SUVs. This type of car will forever remain in the hearts of Russians as a cult car, capable of miracles without any electronic or other bells and whistles. It is not without reason that to this day UAZ cars take first places in various off-road rallies.

But that’s not about that now. One performance quality of UAZ cars is widely known, which upsets the owners of almost all models of these cars. This is the inability of the cooling system to maintain the optimal engine operating temperature in winter. Perhaps one of the most common jokes about UAZ is their felt blankets that cover the engine in winter to preserve heat. The car is compared to horses, which were thus “warmed” by cavalrymen in the winter, besides, the UAZ is known for its “jumping” driving style, about which there are whole legends...

General device

These cargo-passenger cars with carriage layout use closed-type liquid cooling. The coolant circulates in the system forcibly under the influence of a centrifugal pump. The manufacturer recommends using domestic Tosol as coolant. However, in emergency cases, you can fill the cooling system of the UAZ “Loaf” with ordinary water. The volume, including not only the cooling system circuits, but also the heater, on most models ranges from 13.2 to 15.3 liters.

How to make your favorite UAZ warmer?

The reason for such a “cold” behavior of the UAZ is the standard TS-108-03 thermostat, which operates according to a single-circuit circuit. It is installed on almost all old UAZ models. The exception is the UAZ Patriot, which finally used a newer cooling system. Its basis was the TS-107-02 thermostat, operating on a dual-circuit circuit, familiar to VAZ cars.

All other owners can either put up with this state of affairs or try to modernize their equipment using traditional methods. It just so happens that the developments of the domestic automobile industry have to be constantly refined, and parts are taken from completely different car models.

So, in the case of a UAZ, the standard thermostat can be removed and a dual-circuit thermostat from a VAZ car can be installed:

TA 2101-1306010 80°C (3 pipes) - used on VAZ 2101-07, 21213-14, IZH 2126, 2717 vehicles;
TA 2121-1306010 80°C (3 pipes) - VAZ 2121 Niva;
TA 2108-1306010 85°C (4 pipes) - VAZ 2108, 2109, 21099, 1111 OKA.

As you can see, there is plenty to choose from. It’s worth noting right away that thermostats with 3 nozzles are most preferable, since in a 4-nozzle one you will simply have to drown out the “extra” using any available means. The first version of the part is considered ideal, since the pipes are most conveniently curved here and it will be easiest to mount it on the UAZ.

The VAZ thermostat plays the role of an add-on, which, until the engine warms up to operating temperatures of 80-90°C, prevents the passage of liquid into the cabin, driving it in its own small circle (unlike the standard thermostat, which immediately drives the liquid in a single circle, which includes salon). When the temperature begins to rise, the valve gradually opens in favor of a larger circle, and hot liquid begins to flow into the cabin stove. The temperature is equalized throughout the system, and until the engine stops and cools down, the liquid will move only along the external circuit.

There are two installation options: the thermostat is located at the top or bottom of the engine. Both options have their disadvantages and advantages. So, with an upper, more convenient for installation, location, you will have to cut an additional fitting into the system to bleed air, which does not need to be done if the thermostat is installed from below. Although, while pouring liquid, you can slightly loosen the top clamp, insert a thin screwdriver under the hose and thus bleed the air.

DOES UAZ NEED A CURTAIN?

One of the popular methods for improving the performance of a car is installing more advanced parts and components from other brands and models. Anton Utkin talks about how to independently upgrade the UAZ engine cooling system.

Many people have probably seen: in winter, the hoods of army UAZ vehicles are covered with special quilted blankets. Car enthusiasts who have dealt only with Lada cars are perplexed: is the blanket a technical necessity or simply a glorious military tradition preserved from the times when cavalrymen carefully covered their horses, protecting them from colds? Alas, insulating the UAZ engine compartment is a necessary measure: the archaic design of its cooling system is not capable of maintaining the optimal thermal conditions of the engine. Characteristic features are very slow warming up and low (60-70°C) operating temperature in cold weather. Meanwhile, there is a simple way to increase it by one and a half times (that is, bring it back to normal) - just replace the outdated single-valve thermostat with a more modern one. The plant also followed this path, using a TS-107-02 two-valve thermostat on the new UMZ-4218 engine with a volume of 2.9 liters. With it, the UAZ engine, of course, did not warm up as quickly as the Zhiguli one, but at least it did it no slower than the Volgov one.

However, 2.9 liter engines are still rare, and almost all UAZ cars run on the roads with a low-temperature single-valve thermostat TS-108-03. The idea of independently replacing it with a two-valve Zhiguli appeared a long time ago - around the same time as the expression “warm, like in a Zhiguli.” The magazine has repeatedly talked about how car enthusiasts did this in Volgas. Unfortunately, they often only copied the VAZ piping diagram, accepting in advance its main drawback - the difficulty of replacing the thermostat in road conditions. The latter is very important, because the quality of thermostats from the Stavrovsk ATO plant (they are used by Russian car factories) is very unstable - one copy can work for twenty years, while another will jam in a month. Therefore, it is better to embed the thermostat not into the lower (outlet) radiator hose, as is done on VAZ and AZLK cars, but into the upper (supply) hose - then it can be easily replaced without draining the Antifreeze and without dirtying your clothes.

This is what the UAZ engine cooling system with a Zhiguli thermostat looks like: 1 – radiator; 2 – hose with an internal diameter of 32 mm; 3 – thermostat TS-103; 4 – steel tube with a diameter of 32 mm; 5 – intermediate pipe with a diameter of 45 mm; 6 – hoses with an internal diameter of 45 mm; 7 – standard thermostat cover.

The thermostat TS-103, used on VAZ-2101–2107 and 21213 cars, with an angle of 122° between the side pipes, is best suited for UAZ, and more often than other modifications are on sale. Several pieces of rubber reinforced hoses with an inner diameter of 32 mm, straight and curved, with a total length of about half a meter can be borrowed from VAZ, AZLK, Tavria cars, and two thin-walled steel tubes with an outer diameter of 32 mm can be borrowed from VAZ-2108, Oka, "Tavria" and "Moskvich-2141" (with a VAZ engine). Eight worm-wheel clamps with a diameter of 32–50 mm will help secure all this “equipment” on the UAZ.

First, we completely disassemble the standard hose system, disconnecting them from the radiator and water pump pipes. We remove the standard thermostat from the housing and, having lubricated the gasket with sealant, put its cover in place. A curved piece of tube with a diameter of 32 mm must be welded (or soldered with brass) into a metal pipe with a diameter of 45 mm connecting the two parts of the radiator outlet hose - for a small circulation circuit. On UAZ cars with a carriage layout (“tadpole” and “loaf”), a thin pipe for the “stove” is already welded in there, but it won’t hurt. When connecting the Zhiguli thermostat to the UAZ radiator pipes and thermostat cover, no adapters are required - a hose with an internal diameter of 32 mm, although with difficulty, is pulled onto pipes with a diameter of 38 mm, especially if they are lubricated with a slippery sealant (Germesil, etc. ). The figure shows a visual diagram of connecting the hoses, but in fact the vertical branch of the small circuit is located closer to the radiator, and the thermostat occupies an almost horizontal position just below the radiator filler neck.

The experience of operating a UAZ with a Zhiguli thermostat showed the complete success of such a modification. Fears that a 40% reduction in the cross-section of the radiator supply branch could cause engine overheating were not confirmed. Not at all, even with a loaded car in the heat of summer Moscow traffic jams, it stably maintains its 90° C. The same 90° on the temperature indicator in winter, and without any blinds, aprons or blankets. At the same time, the main radiator is cold, like snow on the side of the road, but the “stove” is blowing with a sultry dry wind - the car has become much warmer. And the engine itself seemed to have received a second wind. Previously, at 60° on the indicator, it pulled poorly and responded with failure to opening the throttle. Now, heated to 90°, he already growls with pleasure, taking the load. In general, the game is worth the candle, try it - and you won’t regret it!

Method for connecting a VAZ thermostat

BMW spare part will improve heating

Briefly, installing a VAZ thermostat on a UAZ car is as follows.

Completely or partially drain the coolant and remove all existing hoses, remove the old thermostat, first removing its cover.
Place a short pipe (narrow side) on the outlet of the new thermostat that is closer to the closed end, after lubricating the connection with sealant, tighten the connection with a clamp.
Using any sharp tool, cut a hose whose diameter is larger than the previous one, leaving enough so that you can connect the standard cover with the hose to the second outlet of the new thermostat. These connections only need to be pressed a little with clamps.
Replace the thermostat cover. Select the most convenient position of the thermostat and now tighten all the clamps.
Using a pre-prepared tee, connect all the pipes into a single system, lubricate the connections with sealant, and tighten everything with clamps.
Fill with coolant.
Start the engine and run it at idle speed until all air is removed from the system.

Just like that, a cold UAZ turns into a comfortable, warm car.

Source: prouazik.ru

Heat Resistance Test

Our “Patriot” from birth did not want to work within the temperature limits allotted to it. In summer the traffic jams almost boiled, and in winter on the highway there was only enough heat to blow across the windshield. So we lived with the car. When it was hot, when you stopped, you would run the engine at higher speeds so that the fan would spin faster, and in the winter, they would put cardboard in front of the radiator and caulk the cracks. This fuss does not suit a modern car - let him monitor his temperature, and we will help him.

In the standard version, the thermal regime is regulated by a thermostat, an auxiliary electric fan in front of the radiator and a viscous coupling of the main fan - the devices are mechanical and slow. What if you entrust it to electronics?

From a gearmotor with a built-in programmable microprocessor “Silich” (they are produced by the company of the same name (www.silich.ru)) and a conventional ball valve, a thermostat with a flow area of 40 mm was obtained. The time required to open it completely is only 3 seconds. (The bypass is constantly open, but its cross-section was limited by a throttle washer with a diameter of 10 mm, selected experimentally.) Setting the response temperature of the gearmotors is very simple - using a button on the housing according to the on-board computer readings. Instead of the standard ones - a viscous coupling fan and an electric one - two 360 W electric fans from Kalina with programmable power regulators will operate (ZR, 2008, No. 6). We take the temperature of the working fluid from a sensor installed in the body of the standard thermostat.

Instead of the regular cardboard, we install good old blinds in front of the radiator. They help warm up the engine faster and keep you warm in winter. They were controlled by the same “smart” gear motor. And the radiator itself is now from Volga. It is wider and can be installed higher, in the flow of incoming air. The old one, with a hole for the “starter” in the lower tank, was in the shade and could not effectively dissipate heat. However, the plant has already solved this problem - on new cars the radiators are wide and “drafty”.

Let's start the engine. The thermostat and blinds are closed, the fans are silent. As it warms up, the thermostat comes to life first, periodically opening first at a small angle, and then completely. Then the blinds open. But the car is standing still, there is no headwind, and the fans come into action one by one. The cycle is complete - all components are functioning as they should. We turn off the engine - the fans run for another 30 seconds, blowing the heat away from the engine, behind them the blinds and thermostat close.

Test runs with the electronic system showed very good results. On the highway and in traffic jams, the temperature deviation from the set point was only 2°C. I wonder what will happen off-road?

We start with a freshly plowed field. After a kilometer and a half of driving through the arable land, the sound insulation of the engine compartment began to smoke from the hot collector. The temperature is still normal - a range of 3°. Let's complicate the task - we'll simulate a thermostat failure. In this case, it can be opened manually with a screwdriver. The function of maintaining the temperature is taken up by the blinds. What if the radiator is broken? We turn off the thermostat, leaving only a small circle for liquid circulation. The fans roar at maximum power, blowing through the engine, the engine temperature has exceeded a hundred, but the liquid does not boil, and you can drive slowly.

The final survivability test (failure of all electronics at the same time) after such an experiment is child's play. We open the thermostat and blinds manually, connect the fans to the standard wiring - there’s no way to freeze the motor.

Central Russia with its meager summer and the Caspian haze in mid-July are two different things. How will the Patriot behave in warmer climates?

PLUS FORTY IN THE SHADOW

The vehicle is loaded according to the regulations, and instead of a cannon on the towbar (UAZ is a military vehicle) there is a trailer weighing one and a half tons. The road to Volgograd, outside the window it is still +30°C, the cooling system is set to 92°C, and the operation of all systems is controlled by the on-board computer. Traveled 957 km, average fuel consumption 15.57 liters. Not much considering the full load and trailer. What if you warm up the engine a little? After all, the hotter it is (to a reasonable limit, of course), the more economical it is. We set the temperature to 102°C and set a course for Astrakhan. It got “warmer” outside to 42°C, the speed is about a hundred, the hot wind whistles through the open windows, but it doesn’t bring relief, it’s still hot! The plastic upholstery of the tunnel in the cabin heated up to 76°C from the hot neutralizer, you can’t grab the seat adjustment lever with your bare hand, and the engine keeps the set 102–103°C. Consumption dropped to 14.98 l/100 km.

But anyone can drive on asphalt, but what if you try on sand? To the side of the road there are picturesque dunes. We attack them, of course, without a heavy trailer - with it this is simply impossible.

Overboard 50°C! The engine barely turns the wheels, which are stuck up to the hubs in the sand, and every now and then a shovel is used. Instant fuel consumption exceeds 40 l/100 km, the fans roar louder than the engine, but only drive hot air. The temperature jumped to 107 ° C, but the engine did not boil! I can imagine what would have happened to it with a standard cooling system - it would have jammed long ago.

On the way home, we arrange another experiment, especially for those who are afraid of overheating the engine in traffic jams and always keep a huge temperature head start for it. We program the system at 72°C.

The engine seems to have been replaced - it barely pulls up hills in fourth gear, it holds speed worse, and the exhaust has acquired a sharp, unpleasant smell - gasoline does not really burn. The fans work non-stop. No, this is not his regime, and after a while we return to the proven 102°C. Consumption (without a trailer) - 12.45 l/100 km. However, the accuracy of measurements is significantly affected by the “errors” of gas station dispensers - on one of them, 46 liters entered the 40-liter (under the plug) UAZ tank. Nevertheless, even taking into account such “generosity”, the feasibility of altering the cooling system is beyond doubt - if previously the average consumption on the highway never fell below 15 - 16 l/100 km, then on this, not the easiest trip, it was 13.48 l. And the price of a microprocessor is like a resistor on a Kalina fan, only 300 rubles. In terms of gasoline, it will pay for itself already on the first canister!

Source: https://www.zr.ru/content/articles/16593-ekzamen_na_zharostojkost/

Replacing the thermostat on a UAZ

The thermostat is an important part of the engine cooling system. Since UAZ SUVs are quite heavy frame vehicles, their engines are almost always loaded, hence the risk of overheating. It is important that the cooling system works perfectly.

The thermostat is designed to distribute coolant (antifreeze or antifreeze) over the so-called cooling “circuits”. There are only two of them: a small circuit and a large circuit. From the moment the car is started until the liquid warms up to a certain temperature (80-90 degrees), a small circle operates. The large circle turns on after this temperature, this is the “opening” temperature of the thermostat. In a large circle, the coolant flows through a large cooling radiator, which is located in the front of the car.

Maybe repairs are possible? Unfortunately no, definitely change them, since they cannot be repaired. There may be several reasons why you may need to replace the UAZ thermostat:

It may get stuck in the closed position when only the small circuit is operating.
In the open position, when a large circle is running, the machine takes a very long time to warm up.
An intermediate option when the thermostat is stuck in the half-open or half-closed position.
A problem is possible, as a result of which the valve opening temperature may decrease by several degrees, which again will lead to “underheating” of the machine to operating temperature in winter.

This is how they usually check the actual valve opening temperature

From the factory, UAZ vehicles are equipped with thermostats whose opening temperature is too low (82-84 degrees). Since there is a belt-driven fan installed from the factory to cool the engine, it always runs when the engine is running. Because of this, in winter it is difficult to warm up the car completely, so it is necessary to set the valve to a higher temperature. In summer the situation is reversed - it is necessary to install a valve with a lower opening temperature. The problem can be radically solved only by replacing the original fan with an electric one; it is even better to install 2 electric fans at once.

There were a lot of engines installed on UAZ, so the location of the thermostat may be slightly different for everyone. For example, on engines ZMZ 402 (UAZ loaf), 410, 417 it is located almost at the highest point, so to replace it you will have to drain just a little bit of liquid.

But on the UAZ “Patriot” and on the Hunter it is located in a slightly different place, you can see this for yourself by watching a video about replacing the thermostat on a UAZ Patriot.

Thermostat malfunctions: signs, causes, consequences

Since the thermostat device is quite simple and is not subjected to intense mechanical stress, it can work for quite a long time. There may be several reasons for the breakdown:

Scale on the rod, corrosion on metal parts. As a rule, deposits in the cooling system appear due to low-quality antifreeze and untimely replacement. Scale on the thermostat parts impedes the movement of the rod and valves, after which the thermostat stops responding correctly to changes in coolant temperature.

Vibration damage. More often, such a nuisance happens with defective or low-quality products in which the joints and connections are not sufficiently rolled. If the copper cylinder is not properly sealed, coolant will get inside and prevent the thermostat from operating.
Destruction of the rubber seal due to high temperature. Overheating can damage already “tired” rubber, after which cracks and leaks form in it. The membrane inside the working part (between the wax filler and the rod) also suffers from overheating.

If the thermostat breaks down, it begins to respond worse to temperature changes, and then jams. The thermostat valves may close the pipe leading to the radiator or to the bypass channel, or may stop in the middle position.

The engine takes a long time to warm up - the pipe to the radiator is open, the antifreeze cools, preventing the engine from warming up.
The engine overheats (arrow in the red zone) - antifreeze does not reach the radiator.
The engine takes longer to heat up than usual, and under load the temperature rises sharply - the valves are stuck in the middle position, part of the coolant constantly passes through the radiator, but with heavy traffic this cooling is not enough.
Also, indirect signs of a thermostat failure may be non-working interior heating (“stove” blowing cold air), increased fuel consumption, and deterioration in engine dynamics.

The most severe consequence of a thermostat failure will be engine overheating: in hot weather, a few minutes are enough to bring the engine into emergency condition. But driving with an engine that is not sufficiently warmed up affects its service life: wear of parts increases, and engine oil does not work efficiently.

Malfunctions

As a rule, the thermostat jams directly during operation, but this can happen in two positions:

Closed position. In this case, severe overheating of the engine can occur not only at high air temperatures, but even at slight frost. The thermos may not open completely; the motor in this position, although it will overheat, will not boil.
The valve is stuck open. The result of such a breakdown is that too cold liquid gets into the engine when it starts, and while driving it will not warm up to the required temperature.

Thermostat. Marking.

Inquisitor » Вів chervenya 09, 2009 13:07

Onega » Thursday 09, 2009 13:40

Kostya, I have a Merc with a 100_(102) engine, mine is 82 degrees, Max got the same one, but 87 degrees. I took it to Perov, in the first Mercedes pavilion. Last year, at 82 degrees it was about 150 hryvnia, at 87 - about 120 hryvnia.

If I find the box, I’ll write down the label.

If you're wrong, HellCat will correct you.

There is nothing dearer to me than a faithful friend and off-road. More kilometers on the way to my native fire (c) Sergey Krivtsov

UAZ 31512, 1990, awning, collective farms, 417_y dvizh:ek, self-block (armored personnel carrier) tel. 8,050 three threes - two zeros - seventeen. On air I respond to UT4USE

Inquisitor » Viv Chervenya 09, 2009 15:55

80 degrees in native

RotoR » Mon 11, 2010 0:43

I also saw that my engine was cool. So I decided to find a thermostat. The UAZkins on the 417 did not find an engine with a temperature of more than 70, but the toad crushed the Mercedes one. Perov for it is 200 UAH. requested. Inflation.

I decided to experiment with my own. I carried out a series of experiments in a saucepan and came to a conclusion. That the native one, at the extreme position, showed 73 degrees, the beginning of the opening and at 95 it opened completely with a hole of 6 mm. (although according to the characteristics the stroke is 8.5 mm. Maybe this is due to the fact that in the summer it boiled in 40 degree heat). After I unscrewed the screw, I got the second extreme position. Everything would be fine. Because the initial opening temperature became 80 degrees. But! At 95 degrees and above, the hole became even smaller. only 4 mm. It won't be enough!

Total. I think I can try it for winter. But for summer - absolutely not. This is probably the wisdom of using Merc's 82 or 87. It's a pity that for the purity of the experiment they didn't get into my pan.

I'll try and see. I'll tighten the screw back.

Sorry if the material is not entirely relevant to this topic. I just wanted to keep the conversation going about something sore.

oleg_mt » Mon 24, 2011 15:58

Onega wrote: Kostya, I have a Merc with a 100_(102) engine, mine is 82 degrees, Max took the same one, but at 87 degrees. I took it to Perov, in the first Mercedes pavilion. Last year, at 82 degrees it was about 150 hryvnia, at 87 - about 120 hryvnia.

If I find the box, I’ll write down the label.

If you're wrong, HellCat will correct you.

Mykola STARyy » Mon 24, 2011 16:57

oleg_mt » Mon 24, 2011 17:25

Re: 80 degrees in native

Onega » Mon 24, 2011 17:55

UAZ 469 › Logbook › Replacing the radiator and installing a thermostat from VAZ

I've been thinking for a long time that something needs to be done with the cooling system. I don’t drive a UAZ in winter; we only use it in summer and autumn, for fishing or doing housework. Thoughts about lousy heating and temperature stability when passing through fords and puddles in the fall were constantly present. The temperature drops, so does the power, and the risk of staying in a river or puddle increases. This action coincided with the replacement of the radiator, which had already been soldered and was still leaking, and the replacement of the half-pump. This time the leak was at the very bottom from under the metal mounting pads. Then I came across a sale (in the Flea Market section on uazbuka.ru) for inexpensive new copper three-row radiators, but from Andoria. I figured that 4300 (with delivery) is in any way more profitable than 6600 (the price of a new one in the store), of the minuses: - there is no possibility of using a crooked starter, but I figured that in 7 years of owning a UAZ they never used it, even when the starter broke, then at all lost; — the entrance and exit on the other side turned out to be somewhat advantageous; — it doesn’t fit in width, it was solved by using rubber bands from some shock absorbers, the height is normal, it doesn’t reach the hood. I started by spending several hours studying the topic. “The main thing is not to be afraid!” Go! The radiator has arrived. I bought a WEEM thermostat for 85 degrees, I don’t know why from the VAZ department, a semi-pump (maintenance-free), a set of rubber pipes (two large with a diameter of 44-45, one smaller with a diameter of 35-37) for the 469, a couple of pipes (one long with two bends and one with a bend of 135 degrees) from VAZ, clamps. I dug up a thin wall f40 from my friends, bent it a little, and asked them to make a tee. First, I screwed the pipe in a bend so that it wouldn’t touch the pulley.

Radiator installation

The radiator is completely assembled, all that remains is to install it in the car and secure it.

After the radiator is placed inside the car, you need to tighten two bolts from below and secure them, put on the lower pipe, and then install the protection. After tightening the lower radiator mounting bolts, you need to install the viscous coupling, and only then secure the radiator from above.

Now you need to adjust the gap between the diffuser and the fan: it should be the same over the entire rotation diameter of the fan. If the gap is different, you need to move the casing relative to the fan itself, and fix the shifted casing.

Fill the cooling system with antifreeze recommended by the manufacturer for your car model. After installing our spare parts, the noise when the car is running has decreased significantly, the engine runs smoothly.

UAZ Patriot and thermostat

The UAZ Patriot SUV is equipped with a ZMZ-409 gasoline engine, which requires cooling. If the cooling system is faulty, the engine temperature will rise rapidly during operation, which will lead to serious consequences. To eliminate such consequences, it is necessary to monitor the functioning of the cooling system and if a temperature above 90 degrees is detected on the sensor, you should stop and determine the malfunction. An important link in the operation of the cooling system of the Patriot engine ZMZ-409 is a device such as a thermostat. This is what this material will tell you about today, let’s figure out why it is needed, how and with what to replace it on a UAZ Patriot SUV.

The design of the UAZ Bukhanka engine cooling system

UAZ “Bukhanka” is a real all-wheel drive SUV that can go where other SUVs cannot. This UAZ model has been produced since 1957. This car is used as special equipment in enterprises, as well as by ordinary people for fishing or hunting trips.

UAZ “Bukhanka” accommodates up to 10 people

This car is valued for its cross-country ability and maintainability, the prices for spare parts for it are affordable for most owners, and repairs can be carried out independently. Two engines ZMZ-402 and ZMZ-409 were installed on the Bukhanka; if you want to repair the Bukhanka yourself, then you will be interested in the design of the UAZ Bukhanka engine cooling system.

Purpose of the product

The thermostat in the ZMZ-409 cooling system is designed to distribute the flow of engine coolant. Thanks to it, the liquid is distributed into two circuits. The first circuit has a small circle, and the liquid circulates in the cooling jacket and the interior heater radiator. The second circuit also includes the circulation of liquid through a large radiator.

Thus, we can say that a thermos is a kind of regulator that opens a large circle of circulation of coolant after it has been heated. If it were not there, then when the engine was started, fluid would immediately circulate in both circles, which would lead to a very long warm-up of the ZMZ-409 engine.

Peculiarities

The standard Ulyanovsk-made thermostat on the UAZ Patriot SUV Euro-3 and Euro-4 has an extremely short service life. To be more precise, its malfunction lies in the fact that the temperature of the coolant decreases. That is, it was established from the factory that it should operate when the engine temperature reaches 87 degrees and only after that it should turn on and function in this mode. Thanks to the temperature of 87 degrees. (operating temperature of the ZMZ-409 internal combustion engine) ensures normal operation of not only the internal combustion engine, but also the interior heater. When the standard one malfunctions (a very common problem on Patriots), the temperature drops to 76-77 degrees. As a result, the engine operates at the wrong temperature and in the cabin you have to turn the heater control to maximum in order to achieve some warmth in the cabin.

When the thermostat is faulty, it cannot be repaired and must be replaced with a new one. But you shouldn’t rush to change the awl for soap, because you can install a higher quality product, like those from Pazhdero. “Pekar” is also known, but its operating temperature is 80 degrees, and in fact it does not rise above 75.

The Tama thermostat is characterized by the following features: it raises the antifreeze temperature one degree higher than standard mechanisms. That is, “Tama” has an operating temperature of 88 degrees, while the standard temperature is 87. On the UAZ Patriot ZMZ-409 SUV with environmental standards Euro-3 and Euro-4, the “Tama” thermostat is installed without changes, since it is sized they are similar.

If you are the owner of an SUV with Euro-2 or lower, then you can install a Tama thermostat, but you will need to replace the plate with the one installed on the standard one. That is, replacement is needed so that “Tama” can block the inlet hole on the pump. In order to install a Tama thermos on a UAZ Patriot SUV Euro-2 and below, you need to adjust it to the standard size.

After replacement, the service life of this unit will be much longer than the standard one, and in addition, the interior will become several degrees warmer with the same position of the heater control. Therefore, if you are wondering which thermos is best for your Patriot, then there is only one solution - “Tama” from Pajero.

So, we looked at what the thermostat on a UAZ Patriot with a ZMZ-409 engine is, and what the operating temperature is. Let's consider when a product needs to be replaced or how to determine its malfunction?

Malfunctions

The first sign of a thermos malfunction is a violation of the temperature regime. That is, if you notice that the operating temperature of the engine is not 87 degrees, but lower, then you should think about replacing the thermos soon. It can also jam, causing the engine to reach temperatures above 87 degrees. In this case, you need to lift the hood and make sure that the cooling fan is working properly and that there is antifreeze in the expansion tank. If the fan is working properly and the antifreeze is normal, then most likely the plate is jammed, as a result of which the liquid does not flow in a large circle and does not cool.

In this case, it is necessary to remove the thermos (we will look at the process below) and check its serviceability. To do this, the product is placed in a container of water, after which the water must be heated. If the water is brought to a boil, and the valve does not react in any way, then it is faulty and requires replacement.

The product is considered working when:

the valve opening temperature is 78 degrees;
its full opening temperature is 87 degrees.

Replacement

If the operating temperature of the thermos is violated, the product should be replaced. Replacing the thermostat on a UAZ Patriot SUV is carried out in the following sequence:

First, you need to drain the antifreeze.
The fastenings of the power steering pump are unscrewed. The pump is diverted to the side.
The clamp is loosened and the radiator hose is disconnected from the housing where the thermostat is installed.
There are wires on its body that need to be disconnected.
Next, you will need to loosen the upper clamp on the connecting hose of the thermostat and pump.
The screws securing the housing in which it is installed are unscrewed.
Before removing the body, you should loosen the lid and then remove the thermos body.
Now you can unscrew the bolts securing the thermos body cover and clean the old gasket.
After this, the thermostat is removed and replaced with a new one.

The purpose of the thermostat in this car

The device is designed to redistribute flows during coolant circulation between the so-called small and large circles. In the first case, the thermostat on the 409 engine closes the circuit in a small circle when the liquid circulates in the cooling jacket and radiator of the UAZ Patriot heating system. This situation occurs when the engine warms up to operating temperature. When a certain temperature limit is reached, the valve inside the thermostat begins to move, thereby opening the path of liquid in a large circle. In this case, the coolant circulates through the main radiator, which, with the help of a fan, removes excess heat. If faulty, replacement is required.

UAZ Patriot and thermostat

What to do if the thermostat fails

If a thermos on a UAZ Patriot breaks down, there are two options for fixing this problem:

Buy an original part from a domestic manufacturer.
Buy a foreign analogue of much better quality, for example -.

As practice shows, imported mechanisms last much longer and perform well in a wide variety of operating conditions. If you decide to install a Tama thermostat on the Patriot engine, you should take into account that its operating temperature is 88 degrees. This is a minor difference compared to a thermostat from a Russian manufacturer. In addition, the Japanese part has similar parameters to the domestic ones, which means there will be no problems with its installation.

Purpose of the product

Peculiarities

Malfunctions

The product is considered working when:

the valve opening temperature is 78 degrees;
its full opening temperature is 87 degrees.

Replacement

If the operating temperature of the thermos is violated, the product should be replaced. Replacing the thermostat on a UAZ Patriot SUV is carried out in the following sequence:

First, you need to drain the antifreeze.
The fastenings of the power steering pump are unscrewed. The pump is diverted to the side.
The clamp is loosened and the radiator hose is disconnected from the housing where the thermostat is installed.
There are wires on its body that need to be disconnected.
Next, you will need to loosen the upper clamp on the connecting hose of the thermostat and pump.
The screws securing the housing in which it is installed are unscrewed.
Before removing the body, you should loosen the lid and then remove the thermos body.
Now you can unscrew the bolts securing the thermos body cover and clean the old gasket.
After this, the thermostat is removed and replaced with a new one.

The manufacturer recommends installing a similar device, otherwise it is not responsible for the consequences. But this article makes it possible to conclude that it is better to replace the standard thermos with a foreign analogue. Installation of a new product is carried out in the reverse order of removal. After installation, fill in the liquid and check what the operating temperature of the device is now, which should be 87-88 degrees, depending on the installed thermos model.

To summarize, it should be noted that the serviceability of the thermostat on the UAZ Patriot SUV and other cars is very important, since its failure leads to the impossibility of further movement. Good luck with your choice and replacement at home.

Source: prohodimets.ru

Cooling system diagram for ZMZ-402

It's quite simple. This power unit is cooled by liquid that passes through two circuits.

The system is built according to a ring scheme and consists of several main components. The liquid moves from the radiator through the pipes to the thermostat, then passes through the engine cooling jacket. Then, through the water pump, it returns to the radiator. In addition, the cooling system of the UAZ “Loaf” with a 402 engine includes an electric fan, a temperature sensor, and heaters. Let's look at each element separately.

This is the most delicate component in the system. It fails most often - modern spare parts are not of very high quality. The function of the thermostat is to control the flow of coolant through the engine. The ZMZ-402 unit, like many others, has two coolant circulation circles - large and, accordingly, small.

When the driver starts the engine and it warms up a little, the liquid in the cooling system of the UAZ “Loaf” circulates only in a small circle. This allows the engine to warm up faster. When the temperature reaches approximately 70 degrees, the thermostat will work and coolant will flow through the cooling radiator in a large circle. Operating temperatures for the 402 engine range from 82 to 90 degrees. If the engine does not warm up to these temperatures, this indicates that the thermostat is faulty. Often, due to wear, it jams and does not open.

This is a very important element. Due to it, liquid can circulate directly throughout the system. In this engine, antifreeze circulates constantly forcibly. The pump consists of several elements; if necessary, it can be easily disassembled. The pump is located in the front part of the cylinder block, and it is driven by a belt drive.

How to check the functionality of the thermostat

After the device is replaced with a new one, you need to start the engine and check the cooling system. To do this, open the radiator cap and watch the antifreeze level. Often, when removing the pipes, an air lock is formed, due to which the engine does not cool, and the heater in the cabin blows exclusively cold air.

In order to remove the airlock, you can place the car with the front facing up at an angle of 45 degrees and deliberately decelerate the car. The cork should disappear after 10–15 minutes.

There is also a second way - open the cap on the radiator and pour antifreeze directly into it until the full value is reached. After each topping up, it is necessary to compress and unclench the pipes, thereby expelling the air. Everything will be ready when hot air comes out of the stove and the antifreeze does not float to the surface with bubbles.

The easiest way to check the functionality of the device is to look at the condition of the pipes. Carefully touch the pipes and feel their temperature. If one of them is hot and the other is cold, then the device must be replaced.

There is also a second method by which performance is checked at home. The device is placed in a pan of water and monitored. The water will heat up and as soon as it reaches 95 degrees, the valve cover should open. If this does not happen, then the device is inoperable.

Summer and winter thermostat ZMZ 406, 405, 409. Pros and cons.

The topic of the article is thermostat ZMZ 406, 405, 409. In our engine industry, I cannot understand one simple thing. I get the impression that the engine design bureaus do not monitor their colleagues in the craft at all. The ZMZ designers ran and jumped onto the same rake that AvtoVAZ stepped on.

Bugs and rakes

What happened to AvtoVAZ. The Fiat engine with a capacity of 1200 cc was brought to 1800 cc by clean boring. Judging by the fact that the pump and cooling channels remained standard, no one calculated anything. Result: continuously running fans on the Niva and Shnivy in warm weather. Now we take ZMZ 406. In general, we have never noticed any special problems with overheating. But using the same boring method, we make 2500 from 2300 cubes, and then even 2700. Both the pump and the channels remain original. The result is a cooling system on the ZMZ 409 that cannot cope with its tasks, and simply a nightmare for any “gazelist” - cooling the ZMZ 405, on a cargo gazelle or minibus.

Options for fighting

To date, several options have been tested and rolled out.

Replacing viscous couplings and electric couplings with electric fans from just about anything.
Insertion of an electric pump into the stove tract to improve circulation
Reduced diameter pump pulley
Winter and summer thermostat

I’ll tell you a little more about thermostats.

Thermostat ZMZ 406, summer and winter

thermostats of different opening temperatures Our sellers do not bother themselves with much mental activity, so if you ask a question about a thermostat, they will sell you a factory thermostat with an opening temperature of 85 degrees “Comrade Celsius”. In fact, thermostats are also available with other characteristics. For our vast homeland, I keep three “temperatures”. 85 (factory setting), 80 and 70 degrees. For the middle zone, the summer option is 80 degrees, for the South - 70. I will say right away that from the point of view of classical injection engine building, this is the wrong approach. In a carburetor engine, the operating temperature is set by the thermostat. In an injection engine, this is done by the brains and firmware. If the thermostat opens before the engine has reached operating temperature, the brain will assume that it has not warmed up and will “throw in” gasoline. If it opens later, then the glow ignition elements are overheating. Therefore, by installing a “summer” thermostat ZMZ 406, we initially get higher fuel consumption. The choice is up to the client. Or increased fuel consumption or a broken cylinder head gasket. I prefer thermostats from Vladimir. There are fewer defects and variations in parameters than others. On their website they honestly write that they use an imported thermoelement. I complete the thermostats with a rubber sealing ring so that the service or client no longer has to run around shopping for small items. One more point regarding the Elekton brand: it is their thermostats that are in the factory boxes.

Elekton thermostat, 70 degrees

Please remember that no summer or winter thermostats can replace high-quality antifreeze and the correct plug on the expansion tank.

zmz-fr.ru

Removing and installing the thermostat UAZ Hunter 31516

Method for connecting a thermostat to a UAZ

General device

How to make your favorite UAZ warmer?

DOES UAZ NEED A CURTAIN?

Method for connecting a VAZ thermostat

Heat Resistance Test

Replacing the thermostat on a UAZ

Thermostat malfunctions: signs, causes, consequences

see also

Comments 22

Malfunctions

Thermostat. Marking.

80 degrees in native

Re: 80 degrees in native

UAZ 469 › Logbook › Replacing the radiator and installing a thermostat from VAZ

Radiator installation

UAZ Patriot and thermostat

The design of the UAZ Bukhanka engine cooling system

Purpose of the product

Peculiarities

Malfunctions

Replacement

The purpose of the thermostat in this car

UAZ Patriot and thermostat

What to do if the thermostat fails

Purpose of the product

Peculiarities

Malfunctions

Replacement

Cooling system diagram for ZMZ-402

How to check the functionality of the thermostat

Summer and winter thermostat ZMZ 406, 405, 409. Pros and cons.

Bugs and rakes

Options for fighting

Thermostat ZMZ 406, summer and winter