DIY radiator repair

If a car's radiator leaks, then most of us resort to replacing it. However, in most cases it is possible not to change, but to repair the radiator. Sometimes no skills are required, but sometimes it is impossible to do without knowledge in the field of welding or soldering. We learn to determine the condition and try to restore the radiator with our own hands.

The most common problem is when the radiator leaks due to old age. Coolant (coolant) runs out of the joints between metal and plastic, which automatically leads to overheating of the engine. It is not always possible to find a replacement radiator, and repairs will cost at least 2 times cheaper than a new one.

Further we will talk about car radiators in general and it does not matter if it is a repair of a heater radiator, an air conditioner radiator or a radiator of the engine cooling system.

Repair of a radiator with chemistry. Minor damages can be repaired with special products known on the market as radiator refurbishing fluid, radiator sealant, or powder reductants. The principle of operation is approximately the same: pour the radiator reductant into the engine cooling system (SOD). The resulting mixture will seal cracks when exposed to air.

Chemistry is different from chemistry, therefore, it is impossible to answer for the quality of such a method as a whole. For example, a low-quality reductant may not help, but, on the contrary, harm it by clogging up the entire SOD. For example, the stove will stop heating and it will be necessary to flush the SOD or change the radiator of the stove. Better chemistry is able to eliminate radiator leakage only for a while (from several days to several months). Thus, chemistry for repairing a radiator is only a temporary solution to the problem.

There is a popular method for repairing radiators. It consists in patching holes using cold welding (a material similar to plasticine, which hardens after use). It is better to close up a small hole in the radiator after degreasing the work surface well. If the hole in the radiator is large, then a piece of tin can be used as a patch, which is again glued with cold welding.

We repair the radiator honeycomb with a mixture of epoxy resin and hardener. Degrease and pour the substance into the damaged honeycomb and level it with a spatula. Now the holes in the radiator are 100% sealed.
In general, the folk method involves the use of many materials for sealing, I just showed the main ones. Whether this approach can be called a high-quality radiator repair, decide for yourself.

The following instruction assumes knowledge of basic welding and soldering skills.
To repair the radiator permanently, it must be removed, but before that, the coolant must be drained from it (described in detail in the article on cleaning the radiator). Now that the radiator is dismantled, we can determine its condition, whether the radiator can be repaired or replaced with a new one.

Repair the radiator by soldering. We clean the place that will be restored well and solder a piece of sheet brass (brass radiators). Here you need to resort to using a gas torch and a soldering iron.

If the radiator tubes are cracked, then it is better to replace them with new ones. We heat the solder until it becomes soft and take the tube out of the tank. In its place we solder a new one. The disadvantage of this method is the effect of high temperatures on the elements of the radiator, which leads to its internal deformation. Therefore, it is better to use argon arc welding (argon welding).

Repair of a radiator with argon welding. The filler material here is a special welded aluminum wire. Special equipment is indispensable here. It should be noted that places treated with argon will be protected from oxidation.
Repair of a radiator using gas-dynamic spraying. When a special powder is accelerated along the inside of the radiator at a very high speed, a 1-1.5mm thick coating forms on the damaged surface. It makes no sense to describe these two methods, because they cannot be done at home.

There are various ways to repair a car radiator, each of which has its own advantages and disadvantages. In one case, there will be a short-term repair of the radiator, and in the other for a long time. If you doubt your abilities, then it is better to entrust the mission of restoring the radiator to specialists and argon welding. They will not only repair, but immediately clean the radiator and, if desired, install a brass tank.

If the radiator is damaged after a head-on collision of the car, then the repair will cost a pretty penny. It is more correct in this case to buy a new high-quality radiator.

An article on how to repair a car cooling radiator - causes of malfunctions, methods of troubleshooting. At the end of the article - a video about the professional repair of the radiator.

The content of the article:

• Causes of cooling radiator malfunctions
• Typical malfunctions
• How to pinpoint a radiator leak
• Repair methods
• Video about professional radiator repair

After the fuel is burned in the engine, about 70% of the generated energy is converted into heat. Some of the heat goes outside through the exhaust pipe, but most of the heat stays inside the engine, heating it to a high temperature.

A cooling radiator (heat exchanger) is used to prevent engine overheating and dissipate heat into the environment, which is the main component of the vehicle's cooling system. A healthy and well-maintained (clean) radiator maintains optimum operating temperature in the engine, allowing it to run at full capacity.

However, the radiator, like all other elements of the car, can fail and stop performing its function. But at the same time, it is not at all necessary to immediately contact a car service for repairs. As practice shows, in most cases, a heat exchanger malfunction can be eliminated independently. To do this, you just need to identify the cause of the breakdown and know how to eliminate it.

There are not so many reasons causing problems with the radiator, and conditionally they can be divided into three types:

• mechanical damage;
• improper operation;
• normal wear and tear during operation.

You can also add a factory marriage, but this reason is extremely rare. In most cases, the above reasons lead to one consequence - a violation of the tightness of the radiator. That is, it simply starts to leak.

But there is another "result" of breakdown, which can be more likely attributed to improper operation - fouling of heat transfer plates... Simply put, the radiator becomes so dirty that it stops exchanging heat with the environment, since an adhered and dried layer of dirt (dust, insects, poplar fluff) prevents heat from separating from the heat exchange plates.

In this situation, it is hardly appropriate to talk about repairs, because the problem is solved by simply flushing the radiator fins with a stream of running water. By the way, dirt can form not only outside the radiator, but also inside it in the form of blockages, scale and corrosive deposits.

A small stone that accidentally flew out from under the wheel of a car, as well as a serious accident with a head-on collision, can damage the radiator mechanically with the subsequent violation of the tightness.Also, the inept maintenance of the radiator by an inexperienced car owner, when he accidentally damages the housing, heat exchange elements or other parts, can also be attributed to mechanical damage.

Incorrect operation can consist not only in untimely cleaning and washing of the radiator, but also in the use of low-quality coolant.

Poor quality of the liquid can lead to its freezing and "defrosting" of the radiator, even with a slight frost, with a subsequent violation of the tightness. Or the composition of a low-quality liquid can be so aggressive that it corrodes metal. And this eventually leads to the same defect - depressurization and leaks.

In a car, as in other technology, there is nothing eternal. And the cooling radiator is no exception. He and its accompanying parts are also subject to corrosion, destruction, blockages during operation.

Typical radiator malfunctions can be divided into two types: external and internal.

External:

• violation of the tightness of the pipes for the delivery of coolant to the radiator tanks;
• the formation of cracks on the radiator pipes for the supply / removal of coolant;
• violation of the tightness of rubber seals.

Internal:

• the formation of blockages in the conductive pipes that prevent sufficient cooling of the liquid.

Before starting to repair the radiator, you need to determine the nature and location of the malfunction itself. Almost all external malfunctions of the radiator (except for the usual pollution) consist in a violation of its tightness, which means that there must be a coolant leak.

The intensity of fluid flow from the radiator can be different, and at the initial stage it is visually imperceptible, but a rapid decrease in the level of fluid in the tank is noticed almost immediately. After all, a decrease in the level of antifreeze or antifreeze leads to overheating of the engine, which will be immediately signaled by a special temperature sensor on the driver's instrument panel.

There are two ways to pinpoint the location of a fluid leak. In this case, you will need to completely drain the coolant from the radiator, and disconnect the radiator itself, remove it from the car and rinse thoroughly.

It is necessary to plug (close) all radiator inlets and leave only one. Pour water into the radiator through the left hole. Through the same open hole, using a pump or compressor, create excess pressure in the radiator. A stream of water will begin to come out of the hole in the damaged area.

Also, the removed, empty and clean radiator, but with all the inlets plugged, must be completely immersed in a suitable container of water. Air bubbles will emerge from the holes in damaged areas. If air does not come out, create excess pressure in the radiator with a pump or compressor.

There are several ways to repair a radiator, but not all of them are available and are suitable for independent "garage" or "field" repair. Below we will consider the most simple and common methods of self-repair in simple conditions, without special professional equipment.

For outdoor repairs to a cooling radiator, a heat-resistant adhesive sealant with metal powder is often used. Such a composition is often called "cold welding" or "metal sealant". On the market, such sealants can be offered ready-to-use or as separate components, which then need to be mixed until a homogeneous mass is obtained.

Repairing a radiator using external glue-sealant is quite effective, but only subject to compliance with the relevant technological requirements at each stage of work:

• the coolant must be completely drained from the radiator;
• the outer surface intended for repair must be thoroughly degreased and lightly treated with a file or emery cloth until a slightly rough surface is formed;
• to seal large holes (more than 2 mm), metal patches with a degreased and treated surface can be used.

A sealant is applied around the hole (crack). Initial hardening occurs within 2-3 minutes, and full hardening within 24 hours. The product can be used after 24 hours.

The advantage of a metal sealant is that its coefficient of thermal expansion is close to the coefficient of metal, and if everything is done correctly, then the sealed radiator can serve for several more years.

"Chemical sealants" are sometimes also referred to as "radiator reconditioning fluid" or "powder reducing agent". Accordingly, such sealants are powder and liquid.

Eliminating a leak with a sealant (from the inside) is not a difficult process. The sealant is poured into the cooling system, after which it comes into contact with air and creates a polymer plug, which clogs the hole at the leak.

However, this method has a serious drawback - the sealant clogs the cooling system., after which a complete flushing of the system (and an air conditioner with a stove too) is required. Therefore, the internal use of a sealant is advisable only in an emergency, when the leak is urgently needed to be repaired. You can drive with such a sealant no more than 100 km.

Repairing radiators using soldering is considered not only more reliable, but also more difficult and time consuming. However, this self-repair method is not suitable for all radiators. For example, it is better not to use it to repair radiators made of aluminum alloys, which are very difficult to repair under normal conditions. It is better, easier and faster to seal such radiators with metal sealant. Brass devices are considered the most suitable for home repair with a soldering iron.

To solder a brass radiator you will need:

• a soldering iron with a power of at least 50 W;
• soldering acid (acid and zinc solution) - for cleaning metal from oxide;
• borax powder (flux) - to neutralize the oxide film and better spreading of liquid solder;
• solder.
• metal brush, sandpaper or file.

The surface for applying the joint layer must be pre-cleaned from dirt and dust. Signs of corrosion and oxidation are removed with a wire brush. The working surface is treated with an emery cloth (or a file) to a shine, to improve the adhesion (adhesion) of the metal to the solder. The soldering iron tip must be clean and free of old solder and scale. The work surface must be warmed up immediately before starting soldering.

Important! Soldering can only be carried out at a certain distance from the factory seam, since brass has a high thermal conductivity and can melt the factory seam.

The process of soldering a radiator is not as easy as it seems at first glance. If you do not have sufficient minimum skills to work with a soldering iron or you are not confident in your abilities, then it is better to contact a specialist.

If the cooling radiator has extensive damage, but at the same time it is localized (that is, located in one place), then the problem can be solved by plugging the damaged pipes.

Usually, the damaged tubes are tightly squeezed (flattened) with pliers on both sides as close as possible to the damaged area. In this simple way, the leakage of coolant from the defective holes is blocked.

As a rule, such radical actions are taken in the "field" conditions when there is no other way out of the situation. It should be remembered that it is impossible to operate the car for a long time after such a radical repair, and the number of plugged tubes should not exceed 3-4 pieces.

The most recent car models are increasingly equipped with cooling radiators with plastic barrels and an aluminum alloy center section. It should be remembered that it is not necessary to waste time on the repair of such radiators, since they cannot be repaired at all - they must be changed immediately.

Video about professional radiator repair:

The repair of aluminum radiators has always caused a stir, both on the part of the owners of cars and on the part of the craftsmen. The former constantly wanted to fix all the faults, the latter to make money. In this article we will try to consider all aspects of the repair of aluminum radiators. Everything described below applies equally to both cooling radiators and stove radiators.

Most common radiator malfunctions:

• the appearance of cracks in the area of ​​the outlet and supply pipes of radiators;
• violation of the tightness of the tubes;
• violation of the tightness of the seals;
• the appearance of holes and cracks as a result of mechanical damage;
• poor fluid passage, as a result of clogged tubes.

First, let's take a look at the construction of aluminum radiators and what composite materials are used during their production. The first type is a traditional aluminum radiator with plastic tanks, it may differ depending on the model by the type of cup clamping and the manufacture of the core. As a rule, the tanks are clamped with a wave rolling or teeth.

Sometimes it may seem that the difference is only in the method of rolling, but this is not true. Without going into details, we note that the type of gasket used between the bottom of the radiator and the reservoir imposes certain restrictions, or, in other words, entails the use of a specific type of rolling. Now let's look at the types of cores.

Typesetting cores are divided into:

• solid-brazed;
• typesetting (or prefabricated).

Solid brazed

These radiators are more difficult to manufacture, and, accordingly, they are much more expensive than prefabricated ones. The meaning of the core is that it is collected, like copper, but then sent to a special furnace, with an inert gas atmosphere and a strictly defined temperature for sintering. Then, when the core is ready, plastic tanks are connected to it using wave rolling. Naturally, there are also combinations of the above methods in nature.

As a rule, prefabricated models are based on round tubes with a cross section of 7-11 millimeters, and stacked heat sink plates, they are not welded to the tubes, but simply tightly put on them. The advantage of this design is its low cost, since almost all work is done mechanically, without the help of welding. But still there is one type of prefabricated radiators, where the tubes are not rolled through silicone gaskets to a metal mesh, but are soldered to an aluminum one. To these radiators, in 99 percent of cases, the tanks are connected by means of a toothed expansion of a certain type.

A bit apart are all-aluminum radiators, in which the cores and tanks are made of aluminum. The cores of these radiators are always manufactured by all-brazed technology.

But, surprisingly, not a single cooling radiator from a major manufacturer uses this technology, since the tanks may need as much material as the core itself. The only exceptions are exclusive American radiators, they are made under the order of the capricious owner of the "drag" or restored "classics".

In our country, this technology is found either in stove radiators of some manufacturers (for example, Daewoo Nubira, Lanos), or in models of an openly Chinese or domestic manufacturer. But these two described options, although cheaper than a copper-brass radiator, but the quality of their assembly and design is completely copied from the brass models, and inherits all the "innate" shortcomings.In addition to the above, it must be said about aluminum stoves, their tanks are not welded to the grid, as they should be, but glued, and even with the help of glue, which is dangerous to use even to a garden watering can, not like to a heating radiator.

That is, in order to make a high-quality aluminum radiator, which, in addition to a good heat sink, can still withstand mechanical and hydrodynamic loads long time, careful design is required, and the use of sophisticated equipment during production. And this increases the cost of the final product, which will immediately transfer it from the category of leaders, in comparison with the "copper" product, to the level of expensive outsiders.

Since, for example, at a GAZelle, on our roads, a brass radiator rarely drives off without breakdowns 40,000 Km, which is about a year with a daily load of 100 Km. After overhauling the radiator with our own hands, we can double its life time, unlike the factory one, but it is quite difficult to do this with an aluminum analogue, and most importantly, it is not very profitable financially. Here is a reason to ponder whether you need to save money when buying between an aluminum and a brass radiator?

As a rule, craftsmen call stoves and radiators exotic, which can be very rarely found. As an example, you can cite a heating device Opel Omega 1992, it is made of an all-plastic mesh (bottom) and tanks, made in one piece, and connected to an inlaid core, which has oval tubes, with a welded-on turbulator. Apart from this example, there are also a number of rare varieties, but this, again, is rare.

It should be noted that the more exotic the radiator is on your car, the more difficult it is for car mechanics to repair it, and not only because of the complexity of combining different materials, but also because the experience of many craftsmen simply does not make it possible to apply the tried and true one the first time repair option. That is, an inexperienced master will perform repairs at random, while learning the subtleties, so to speak, exercising with his own hands on your radiator, gaining experience for himself.

As mentioned above, plastic tanks make it easier tos and make the design cheaper. But it is necessary to make a reservation, the term "plastic", considering the tanks, is not very correct, since they are based on polypropylene, and no one will disclose the rest of the additives and impurities, survival in a competitive environment depends on it. Here you can find fiberglass reinforcement, fillers, and other tricks.

After a certain time, the plastic tanks dry up, the plastic base changes under the influence of a constant temperature difference, and they become brittle and form a leak. In this case, the best option would be to replace the radiator with a new one, because replacing the reservoir is not always cost-effective. But sometimes, if we consider exclusive models, you cannot do anything, how to repair cracks in the tank with your own hands, but here the second question arises - which repair option is better?

There is three main repair options:

• replacing the tank with a metal one, which is welded or soldered in place of the plastic one;
• soldering the tank with plastic;
• use of special polymers.

The first method is the most reliable, but also the most expensive, and there is still a problem with the second tank (since there are two of them in the radiator). If you replace two tanks, the cost will be such that it is easier to order a new, original radiator, and all the assurances of the masters, such as the radiator will be eternal, you need to ignore it, since the aluminum part also has a certain resource, and it decreases simultaneously with the resource of plastic cisterns. The high price of these tanks is explained by the fact that they are not made by the master himself, but by an industrial plant, like an aviation plant (Antonov Design Bureau or KhAZ), and the master only welds it with his own hands using argon welding.

The next two methods are more accessible, since use of polymers and plastic soldering is both cheaper and faster, and during the operation of an already very old radiator, it will make it possible to "turn over" before purchasing a new one, without large capital investments.But I must say that soldering a complex composition of polypropylene is sometimes even dangerous, you can make it even more fragile in the soldering area.

The repair of the aluminum honeycomb itself always caused a severe headache, both for the owners of the cars and for the craftsmen. The main reason is both sometimes a very complex and almost unrepairable design, and rather thin metal in radiators that do not have “weak points” in the design, so to speak. But let's look at everything in order.

The first type that we will describe is a prefabricated car radiator, which, as we said above, is inexpensive, but its high-quality repair requires quite large material investments, but at the same time it is quite possible with the hands of professionals. Design consists of a honeycomb part, which, by the way, if it breaks, it is not often, as a rule, the rubber seals fail first. Round honeycombs are fixed to the mesh by rolling, through a rubber seal, which is plastic at the beginning of life.

But this is only at first, and only when pouring high-quality antifreeze, then the gasket turns into just a terrible sight. For example, the resource of a German radiator, which is operated on high-quality antifreeze, is about 11-16 years, a Soviet one - 7-11 years, the resource of a modern and Chinese one can sometimes be from 20 minutes to several years.

If the soldering of the central part of this radiator (well, rubbed it, or punched it with a screwdriver) is possible with the help of special solders, then it is profitable and efficient for both sides, it is almost impossible to repair the "sinister connection". Some workshops, at one time developed a composition that makes it possible to solder aluminum honeycombs to a steel mesh, but, of course, it is inappropriate to use it for repairs, for example, for VAZ-2107 products, this option is well suited only for repairing "foreign cars".

This is already a more advanced product, which requires an advanced and expensive intervention during the repair. Since the solid-brazed unit is almost never found in budget cars (for example, Daewoo Lanos installs a solid-brazed version, while Daewoo Sens is type-set), the slightly more expensive repair cost justifies itself almost all the time.

Complication of soldering, for example, of corner honeycomb packages is explained by the fact that different metal thicknesses will not allow the craftsman, even a professional who handles the torch, to melt the solder, the temperature of which often reaches 500-650 degrees, and at the same time not damage the plastic tank.

Removing it for this is also impractical, and you can damage the factory connection, an alternative is a high-quality photopolymer or polymer.

As a result, I would like to say that the aluminum radiators of a car with their plastic tanks, although quite difficult to repair, but with a competent approach and high-quality materials, make it possible to achieve excellent results.