How and with what to solder an aluminum radiator

How and with what to solder or seal an aluminum radiator

An aluminum radiator has many advantages, thanks to which it is installed in many homes. But sometimes it can “please” with the appearance of holes and coolant leakage.

There are two ways to get rid of this drawback:

1. Solder the battery.
2. Seal the hole.

Soldering aluminum is more difficult.

What is the difficulty of soldering aluminum?

This metal quickly reacts with oxygen and any acids. Most often, an aluminum radiator interacts with oxygen. As a result, the metal surface is oxidized and covered with a thin layer of aluminum oxide. It is also known as “oxide film”. This layer evenly covers the entire surface of the product.

On the one hand, this film is useful, because it eliminates any possibility of contact of pure aluminum with oxygen and all other chemical elements or substances. That is, it is a kind of protective barrier. However, this barrier does not allow for high-quality soldering, because the solder must be in direct contact with the aluminum.

If there is no contact, then it will not be possible to solder the radiator well. As a result, the plug covering the hole will not be secured properly. Therefore, small gaps form between it and the radiator itself, which will subsequently begin to let water through.

The simplest solution is to remove the oxide film and then solder the hole.
But it is not correct, because after removing the oxide film, pure aluminum begins to interact with oxygen again, and until the end of soldering, the treated area again receives a protective barrier. The soldering result will be bad.

To solve the problem of removing the oxide film and making it impossible to form further, you need to use fluxes. They are a mixture of inorganic and organic substances. They destroy the oxide film and prevent its formation, they also:

• reduce the tension of the treated surface;
• improve the spreading of solder over the treated area;
• do not react with solder (most types of fluxes).

Fluxes are different:

• cadmium;
• bismuth;
• zinc;
• combined substances;
• flutes (homemade).

Tools and materials

To solder aluminum radiators, you need to have:

1. Regular soldering iron.
2. Burner, blowtorch or gas stove.
3. Crucible (is a fireproof container for preparing solder).
4. Emery cloth.

Source: https://poluchi-teplo.ru/radiatoryi/alyum/payka-otverstiy-i-treshhin-v-alyuminievom-radiatore.html

How to solder a car radiator - how to solder a radiator yourself at home

Frequent car trips are fraught with overheating of radiators, especially those that are blown by a mechanical rather than an electric fan. Overheating is not so bad: we stood there for half an hour, and then we were on our way again. Heat, as well as gravel from the wheels of cars avoiding traffic jams on the side of the road, can seriously damage the radiator. This is the most vulnerable spot in the power unit of any car - antifreeze can leak anywhere.

Even a new aluminum radiator is especially unpredictable, but a copper one will leak along the way and over time. Therefore, below we will tell you how to solder a copper radiator, as well as products made from other materials.

Automatic kettle repair

Kettle - this is what car enthusiasts call a radiator due to the fact that the liquid in it is beyond the boiling point of water - up to 130 degrees. Therefore, instructions on how to solder a radiator will come in handy. Repair of the internal combustion engine cooling system is the most common thing in auto repair shops during any holiday season.

Practice shows that on the road you can fix a leak yourself only temporarily - to the nearest service station. The following can be done as a temporary measure. Grouting powder or corresponding liquids are poured or poured into the radiator.

How to solder a radiator, read below. If, of course, you purchased everything you need in advance and put it in the trunk. These are the two main emergency equipment for long journeys.

Radiator repair is the elimination of leaks in the tubes. If this happens at home, you won’t have to turn to professional aluminum shareholders and coppersmiths. If you have everything you need, you can handle such a problem as repairing radiators on the highway.

To do this, you will need to perform several technical procedures:

• Draining the water/antifreeze, removing the radiator and preparing it for soldering.
• Availability of tools and SOS tools.
• Soldering of the emergency area.

Do not try to make the job easier by soldering without removing the heatsink. The fact is that the leak can be obvious - a stream, but there is a leak that you won’t notice. But after a while, an emergency situation with a coolant leak will occur again.

Removal is necessary, first of all, to diagnose possible water/antifreeze leaks. To do this, close the empty “kettle” with stoppers, except for one, connect an auto-compressor to it and place it completely in a container with water. Where even small bubbles appear, a new breakthrough is possible.

Repairing a copper radiator

Clean the engine cooler from adhering dirt and leaves with a vacuum cleaner and water. Remove defective areas from the grilles on the tubes by carefully cutting them off, clean them thoroughly with a metal brush, sandpaper and a small file, and then degrease them with acetone or any alcohol.

Remember that the cleanliness of the leak site must be perfect so that the solder adheres to the metal everywhere - both on aluminum and copper radiators. Otherwise, the quality of the connection will leave much to be desired.

Now you can solder the radiator with your own hands by performing copper plugging. You need to prepare:

• electric soldering iron with a thick tip for 100 - 150 W;
• any burner;
• solder made from a mixture of lead and tin;
• oxide remover (flux);
• rosin, dry or in alcohol.

POS-60 with low melt temperature will patch a copper radiator. For a brass engine cooler, use index 40, only heating the defective area with a gas burner for a longer time.

After performing high-quality tinning, place the solder heated with a soldering iron over this area evenly over the soldering area. It is better to use any flux instead of rosin.

Restoring duralumin damage

Any welding of aluminum, as well as its soldering, is impossible without cutting off air, otherwise instant oxidation cannot be avoided. Since it is impossible to solder an aluminum radiator like a copper one, it is possible to take solder from bismuth with indexes 33 or 50.

But for it you first need to prepare a powder from four chemical elements that are difficult to find. They are used only at car service stations.

Another method can be used. To do this, have a carbon dioxide cylinder. Direct its jet to the place where the solder is applied. Apply solder and use a soldering iron to place it evenly over the area.

Checking the quality of work is not difficult. After the radiator has cooled down from soldering, pour antifreeze into it. If there is no leakage, place the unit on the car, drive several kilometers, subjecting the radiator to water pressure and heat load.

Remember that DIY repairs are not always the best solution. The problem can be fixed temporarily. Therefore, do not delay and at the first opportunity, seek advice and diagnostics from the service center specialists. Repairing a radiator is a task whose solution should still be trusted to experienced craftsmen.

Photo tips on how to solder a car radiator

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Source: https://instrumentgid.ru/kak-zapayat-avtomobilnyj-radiator/

How and how to solder an aluminum radiator - the best and most reliable way

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When a car or heating radiator made of aluminum fails, many people mistakenly believe that there is no way to repair it themselves. In fact, solving the problem of how to solder a radiator is not so difficult if you want to understand all the intricacies and practice a little.

Why is it difficult to eliminate defects in aluminum?

Aluminum is the third most common chemical element on our planet and combines a lot of excellent qualities: strength and good thermal conductivity with a very low mass. It is indispensable when it is necessary to produce a product of a large area with intense heat transfer.

However, for all its undeniable advantages, aluminum has a big disadvantage - it is difficult to repair. Therefore, soldering an aluminum car radiator or heating system becomes a big problem.

The fact is that this metal is chemically active. High resistance to corrosion is ensured by a durable oxide film that protects aluminum from atmospheric influences.

It is this film that disrupts the soldering process. To achieve a metal-to-metal bond, you need to heat it. In this case, a layer of oxides is necessarily formed, which will prevent contact. The task of the master, when the question arises of how to solder an aluminum radiator, is to break this circle.

By the way, in the case of copper the same principle applies. Copper products are valued precisely because of their resistance to rust, but their unique ability to protect themselves from corrosion turns into a problem during repairs.

How to solder a radiator correctly

To remove oxides from the surface of aluminum, specially prepared fluxes are used. They contain cadmium, bismuth or zinc. It is these elements that help clean the metal surface and thereby connect the product to the solder.

The cost of ready-made fluxes with good quality characteristics is quite high. Therefore, home craftsmen prefer to make such compositions (fluxes) on their own.

To protect the area of ​​the product that needs repair from contact with air, there are several ways:

• using iron rosin flux
• using a homemade flux;
• use of low-temperature solder with sizing.

Sometimes, to solve the problem of how to seal an aluminum radiator, it is suggested to use cold welding. However, this is very unreliable and only works as an emergency measure. Sooner or later the damage will have to be repaired again.

Use of iron rosin flux

There is a simple way to solder a radiator with a soldering iron using rosin-based flux. To do this, the damaged metal is prepared according to the following scheme:

• remove paint residues and all kinds of dirt;
• thoroughly clean the metal with an abrasive;
• degreased with a special solvent.

The preparation must be very conscientious; the entire repair depends on this. Flux is prepared in a metal crucible. Melt the rosin and gradually add iron filings there in a ratio of 1:2. Stir until smooth. Sawdust in this case will be an abrasive.

Next, the surface to be repaired is covered with a thin film of molten flux. The quality of future soldering depends on the thoroughness of the procedure. In this way, aluminum is protected from oxidation.

The materials used in the work emit toxins. Therefore, you need to do everything under a hood, or carry out repairs in a thoroughly ventilated area. If conditions permit, outdoors.

Next, the soldering process begins. Use a soldering iron to grab a little solder and apply it on top of the flux using smooth circular movements. This should be done slowly, carefully ensuring that the solder is evenly distributed over the damaged area.

How does flux behave in this case? Iron filings clean off oxides, and rosin blocks air access to aluminum. The conditions for contact between metals are met.

This method works when you need to solve the problem of how to solder an aluminum radiator if the damage is not great. Large areas cannot be repaired this way. The flux becomes cold very quickly, so soldering a large surface will be problematic.

Do-it-yourself repair of a large surface

Sometimes you have to face the need to repair a large area of ​​an aluminum product. Conventional home methods are not effective. How to seal an aluminum radiator in this case, or how to solder it?

To repair large damaged surfaces, you can use homemade flux.

The area to be repaired is first cleaned and degreased with a special compound. The algorithm of actions is the same as when preparing the surface when using iron rosin flux.

Components for flux are taken in the following percentage ratio:

• potassium chloride - 56%;
• lithium chloride - 23%;
• table salt - 75%;
• sodium sulfate - 4%;
• cryolite - 10%.

The raw materials for melting are ground in a mortar to a powder, poured into a crucible and mixed until smooth, then carefully melted.

If the resulting powders are intended for long-term storage, they should be poured into dark containers with tight stoppers and kept away from sunlight and other heat sources.

How to solder a radiator using flux:

• the damaged area is heated using a gas burner;
• a thin layer of flux is applied to the heated area;
• solder the damage using tin-lead solder with a small addition of bismuth.

You need to know that you should not heat the damaged area with strong fire from a gas burner. This will lead to the area simply being burned through. It is important to choose the level of gas combustion that will allow you to warm up, and not burn through, the aluminum product.

If a gas burner is not used by a professional, he may not know how to light it correctly. It happens that the burner is immediately turned on at full power. As a result, the gas, without having time to ignite, suddenly “sweeps” through the flame of the lighter. The burner will light immediately if you reduce its power.

Repair and soldering of aluminum radiator of complex configuration

When you need to decide how to weld an aluminum car radiator, methods using iron-rosin flux and homemade flux are not effective. Thin-walled car radiator tubes are difficult to solder due to the design features of the product.

In such a situation, you can resort to an alternative method using solder with a low melting point and special sizing.

Preparatory steps before starting soldering:

• remove the oxide film using emery or a special attachment on a drill or screwdriver;
• degrease the defect site with a solvent;
• compress the damaged section of the radiator tube with pliers to reduce the hole.

Then the soldering process begins. First, heat the desired area with the fire of a gas burner. Then a rod of solder with a low melting point is introduced into the flame and passed over the damaged area several times. Each time, particles of solder will cling to the edges of the hole and fall inside the hole. The defect on the tube will gradually heal.

The last thing you need to do with this method is to additionally seal the defect using high-temperature aluminum glue. It will close the smallest micropores, and the repair will be of higher quality.

Source: https://teplospec.com/radiatory-batarei/chem-i-kak-zapayat-alyuminievyy-radiator-luchshiy-i-nadyezhnyy-sposob.html

How to solder an aluminum radiator at home

Here you will learn about how to solder an aluminum radiator at home: the characteristics of batteries, soldering methods, cold welding, the use of glue, how to properly weld a heater and the sequence of actions.

As the long-term practice of using aluminum radiators shows, they have proven themselves to be excellent, but, like other types of heaters, they have leaks and accidents.

In order not to change the entire battery or its section, you can solder it, but you should know and take into account the characteristics of aluminum.

Features of batteries

When radiators start leaking, there are two ways to fix the problem. They can be soldered or glued. Soldering an aluminum radiator is a complex procedure due to the chemical properties of this metal.

When aluminum comes into contact with oxygen, it oxidizes and a thin oxide film forms on its surface. This coating, which is useful in all respects, protects the metal from corrosion when exposed to oxygen, but on the other hand, it does not allow high-quality soldering, during which contact of the solder with its surface is necessary.

If you do not create direct contact between the metal and the solder, the sealed hole or crack will soon leak again. Sometimes new cracks form near low-quality solder, which only worsens the condition of the radiator.

To get the desired result, the oxide film will have to be removed, but if this is done without special devices, then the metal will form it again when it comes into contact with oxygen, so instead of soldering, you will have to remove it all the time.

To break this circle, special solutions for soldering aluminum, called fluxes, were invented.

They have the following abilities:

1. This product is based on organic and inorganic components that can not only destroy the protective film on the metal, but also prevent its appearance.
2. They prevent solder from spreading over the rest of the surface, localizing it exclusively to the area being treated.
3. This flux does not react chemically with solder, ensuring high-quality soldering.

Thus, to the question whether it is possible to solder an aluminum radiator, the answer is unequivocal: “yes”, provided that you have such a tool at hand.

In order for the work to be done correctly, especially if you have to do everything yourself, you need to prepare the following tools:

• soldering device;
• burner;
• a special container for heating solder;
• sandpaper.

As solder, you can use iron filings, rosin or a tin-lead mixture.

Method 1

This method, although simple and even a beginner can handle it, requires perseverance and time. To know how to solder an aluminum radiator using it, you will need to prepare rosin-iron solder.

The sequence of actions that will ensure high-quality soldering is as follows:

1. It is important to prepare the radiator surface for work. To do this, you need to remove it by removing the coolant from the system in advance. The surface of the place where the work will be carried out must be thoroughly washed to remove dirt, then cleaned using emery cloth and solvent. The prepared area must be degreased using any product containing alcohol. After all manipulations, the surface is wiped dry, and the radiator is ready for the next stage of work.
2. Solder is prepared on a crucible, which can be placed on a burner or gas stove. As a last resort, you can use a soldering iron. Rosin needs to be melted, and then iron filings must be added to it and mixed well. The ratio of materials should be 2:1.
3. The flux solution is applied in such a way as to cover the entire area of ​​work , otherwise the newly formed oxide film will destroy all work. Upon completion of soldering, the entire surface to be repaired must be under the solution.
4. The soldering itself is done as follows:
   • a small amount of rosin-iron solder is collected on the soldering iron;
   • it should be applied to the surface of the radiator so that it is covered with flux on top;
   • all actions with a soldering iron are performed in a circular motion, this allows the soldering iron to displace solder particles, which in the process destroy the oxide film, and the presence of rosin does not allow it to form again.

When deciding how to solder an aluminum radiator, you should remember that this method is suitable for eliminating minor defects. If you need to “patch” a large area, you will have to prepare the flux yourself.

For this method, you will have to use solder from a combination of tin, lead and bismuth, and prepare a means for removing the oxide film from the following components:

• cryolite should be 10%;
• add 4% sodium sulfate;
• the proportion of lithium chloride should be 23%;
• the basis of the solution is potassium chloride - 56%;
• table salt the remaining 7%.

By mixing all the components, you get a solution that can cover a large surface area of ​​the heater.

The sequence of actions will allow you to figure out how to solder an aluminum radiator at home:

1. Carry out preliminary surface cleaning work as described above. Aluminum must be clean, dry and free of grease.
2. A special feature of this method is the painstaking production of flux, for which each component is individually crushed to a powder state, after which they must be combined and thoroughly mixed.
3. Heat the finished mixture and pour it onto the solder area.
4. Soldering is performed in the same way as in the first method, making sure to observe the condition that the solder should be under the flux layer.

Regardless of how the soldering was performed, the quality of the work must be checked. To do this, tinted water is poured into the radiator. If after an hour or two it still hasn’t leaked out, it means the soldering was done efficiently.

Application of glue

Using glue is an extreme case when repairs are urgently required, and it is not possible to disconnect the radiator from the heating network. Glue can ensure the integrity of the structure, but not for long, so after the heating season the water needs to be drained from the system, the radiator removed and a full repair made.

You can seal a small hole or crack using epoxy glue, cement, or cold welding.

To apply epoxy glue you will need:

1. Thick cloth that will need to be wrapped around the leak area. This method is not always effective, since the fabric cannot be secured well everywhere. The fabric must be cut into long and narrow strips.
2. Clean the surface at the site of the breakdown. It is necessary to remove all paint and thoroughly clean the metal down to the surface. The prepared area must be washed and degreased.
3. The leak area is smeared with glue, over which a strip of fabric is wound. A layer of glue is also applied to this strip and a second layer of fabric is wrapped. There must be at least four such layers.
4. Secure the resulting layers with a clamp or regular wire.
5. Allow the glue to dry , which may take from 2 hours to 3 days.

In order to improve the properties of the glue, bronze or aluminum powder is added to it. Sealing with cement is done in a similar way, only instead of fabric, medical bandages are soaked in cement.

Cold welding

One of the most reliable ways to “treat” a heater is to cold weld an aluminum radiator. To do this, use either one-color or two-color special sealant. The one-color product must be kneaded well, after putting protective gloves on your hands. In its plasticity, this putty resembles children's plasticine.

The two-color analogue must first be stirred well until the color is uniform, and as it is kneaded, it acquires sticky properties.

The sequence of actions on how to weld an aluminum radiator is as follows:

1. The surface of the battery is being prepared.
2. A piece of putty of the required length is cut and kneaded.
3. Apply the softened weld to the crack or hole and rub the area well, for which you can use a spatula moistened with water.
4. During the entire 5 minutes that the cold weld is setting, you need to make sure that no bubbles appear. If you ignore them, then after a while they will burst and the work needs to be redone. If a bubble appears above the welding site, it must be rubbed again with a spatula and so on all the time until the putty sets.
5. The place where the hole was closed can be additionally secured with a clamp.

You can carry out such work yourself, but provided that the defects are small. In the event of a serious breakthrough, you will either have to call specialists to assess how damaged the radiator is and make repairs, or buy a new section, and in the case of a panel model, the entire panel.

Source: http://netholodu.com/elementy-otopleniya/radiatory/alyuminievye/sposoby-pajki.html

How to solder an aluminum radiator at home with your own hands

Aluminum is one of the common metals that combines many remarkable qualities, including high thermal conductivity with a relatively low weight.

But this material, which is in demand in everyday life and in production, has one significant drawback - it easily reacts with other elements.

This property significantly complicates the soldering of car cooling radiators, for example, and also leads to difficulties when it is necessary to weld a heating battery.

Is it possible to solder aluminum radiators?

An oxide film that protects aluminum from weathering interferes with the soldering process.

Due to the activity of aluminum, there is always a film of oxides on its surface, which prevents connection with other metals. Therefore, soldering radiators based on it seems to be a very serious problem for most car owners and ordinary users.

It is possible to obtain a high-quality and reliable connection of aluminum with another metal only after heating the contact point to a high temperature.

In the process of heating the surface, a layer of protective oxides also forms, which does not allow even a small structural element to be soldered to it. Therefore, when soldering this metal, special fluxes are used to remove the film from the processing site. They contain bismuth, cadmium or zinc. Only with their help is it possible to clean the surface of the metal being welded and make it accessible to working solders.

The cost of branded fluxes with guaranteed quality can be too high. For this reason, home craftsmen prefer to make such compositions (fluxes) on their own. If the proportions specified in the instructions are observed, do-it-yourself solders are not inferior to branded compounds and sometimes exceed them in terms of effectiveness.

What is used for soldering

Before soldering aluminum heatsinks using the proven method, it is important to understand the main components used in the soldering process. For high-quality restoration of the damaged area, it is necessary to use solders with additives of silicon, zinc and a small amount of copper. You can make them yourself or purchase them at a specialty store.

Consumables on the market are represented by standard rods of the TsOP-40 brand, which, according to GOST, have the following composition:

• tin;
• zinc;
• aluminum;
• silicon and copper.

The elements included in the solder (especially zinc) provide high strength to the resulting connection and also guarantee its anti-corrosion protection. With its help, it is possible to solder small structural elements and large parts of aluminum radiators.

Soldering order

Proper organization of the aluminum soldering procedure requires thorough preparation, without which it will not be possible to achieve the desired result. Before soldering the radiator yourself, you should carefully read the relevant instructions. It states that the preparatory stage includes cleaning the area to be restored and preparing a soldering composition of the required quality.

Preparatory operations

Before starting soldering, it is necessary to remove the old coating and clean the soldering area

Before soldering an aluminum radiator using rosin-based flux, the damaged area is prepared according to the following instructions:

1. Remains of the old coating and traces of contamination are removed.
2. The soldering area is cleaned using abrasive.
3. Immediately after this, it is degreased with a solvent.

Before soldering the radiator, you will need to prepare the flux in a metal crucible in advance. To do this, rosin is first melted with a gas burner, after which small iron filings, taken in a ratio of 1:2, are added to the melt (they act as an abrasive). At the same time, the prepared composition is mixed until it becomes a homogeneous mass.

The materials used for soldering are toxic and emit toxic fumes that are dangerous to humans. Therefore, all operations are carried out in the presence of a hood or in the open air. If these conditions cannot be met, the working person will need a respirator.

Elimination of small defects

Upon completion of the preparatory operations, proceed to the soldering process itself:

1. The soldering iron picks up a small amount of solder.
2. Using circular smooth movements, it is applied to the area previously treated with flux.
3. During the processing process, it is important to carefully ensure that the layer of solder is distributed over the surface as evenly as possible.

When soldering, the sawdust contained in the solder removes oxides from the surface, and the previously added rosin blocks the oxygen access channel. As a result, all conditions are created to obtain reliable contact between different metals. This method is only suitable for small damage, the size of which does not exceed a few millimeters. On large areas, the flux cools quickly and does not provide good heating of the soldering area.

Restoring significant damage

To restore a significant area of ​​the radiator, you will need a special composition - flux

The need to restore large-area aluminum surfaces is encountered quite often. You will need a special soldering compound called “flux”. Before using it, the battery surface to be treated is prepared, as was done for small areas.

Initial components for preparing flux:

• potassium and lithium chlorides;
• regular table salt;
• sodium sulfate;
• cryolite.

The mixture prepared in a certain proportion is first thoroughly ground in a mortar to a powder state. After this, it is poured into a crucible, where it is thoroughly mixed until a homogeneous mass is suitable for obtaining a melt.

If the resulting powder is not immediately used for work, it is poured into a suitable container, closed with a tight stopper, and stored in a dark place.

Soldering procedure using flux:

1. The damaged area is thoroughly heated using a gas burner.
2. A thin layer of flux is applied to the prepared area.
3. The damage is soldered with tin-lead solder with the addition of small amounts of bismuth.

When working with special equipment (gas burner), it is important not to overheat the area being restored, so as not to burn it. The strength of the flame is selected so that it is only sufficient to uniformly heat the surface of the aluminum product.

Repair of complex configuration radiators

Soldering a car radiator

There may be situations when it is necessary to restore (unsolder) an aluminum car radiator that has many hard-to-reach places. In this case, methods based on the use of iron rosin flux and home-made flux are not suitable.

Thin-walled tubes of a copper or brass car radiator, for example, are very difficult to solder due to the design features. In this situation, it is recommended to use low-temperature solder (LTS) with simultaneous gluing of the surface to be restored.

To the list of preparatory operations considered, we should add the need to crimp the damaged area of ​​the radiator or stove with pliers, which will reduce the size of the hole.

During soldering, the area to be treated is first thoroughly heated with a gas burner, after which an NTP rod is introduced into its flame. By periodically moving it over this place, you need to try to make sure that the solder particles cling to the edges of the damage and gradually “tighten” it. At the final stage, you will need to seal the defect area using a special high-temperature glue. With its help, it is possible to “fix” all the remaining minor irregularities and flaws.

Using cold welding and glue

When you need to fix minor damage or repair a small chip on the surface of a part, it is best to use an adhesive called “cold welding.” It is a special mixture with a high degree of plasticity, and is made on the basis of epoxy resin - a polymer with unique strength properties. In addition, the composition of “cold welding” includes various fillers (sulfur and plasticizers), which further increase this indicator.

Most often it is produced in the form of two plastic bars that look like children's plasticine. Before use, they are simultaneously kneaded with the fingers, resulting in the desired mixture of two components. To seal the damaged area, it is enough to separate a small piece of the mashed mass and apply it to a previously prepared surface.

Any of the methods for restoring aluminum radiators can be implemented without the help of outsiders. However, if you are not completely confident in your own abilities, it is best to contact a specialized car repair shop.

Source: https://StrojDvor.ru/otoplenie/vozmozhna-li-pajka-alyuminievyx-radiatorov-otopleniya/

How to solder an aluminum radiator: step-by-step instructions and recommendations

Most modern cars are equipped with aluminum radiators. This metal is lightweight, has good anti-corrosion properties, and also has excellent thermal conductivity. In addition, it is significantly cheaper than copper and brass, from which radiators were previously made.

However, aluminum also has a drawback. If a copper (brass) heat exchanger, if damaged, could be repaired without any problems by yourself by soldering the problem area in the usual way, then with an aluminum radiator such a problem will not work. It's all about the chemical properties of this metal. But nothing is impossible. In this article we will look at why an aluminum radiator leaks, how to solder the problem area and what tools will be required for this.

About some features of aluminum

This metal was not chosen by chance for the manufacture of automotive heat exchangers. The fact is that aluminum and most of its alloys have an oxide film that forms a natural barrier that protects against corrosion. This film has high temperature and chemical resistance.

It actively resists conventional fluxes and prevents the application of solder. It can only be destroyed by mechanical surface treatment and special mixtures. This is why it is difficult to restore an aluminum radiator.

We’ll talk a little later about how to solder and, most importantly, how to prepare it for this procedure, but now let’s look at the main reasons why a heat exchanger most often fails.

Despite the fragility of the design, the radiator can last for years. Its main enemies are low-quality coolant and foreign objects that can cause mechanical damage.

Antifreeze or antifreeze themselves are not very active substances that can destroy the protective oxide film, and they practically do not react with pure aluminum.

But if the coolant does not meet the required chemical standards, it promotes corrosion processes, as a result of which the honeycomb walls of the device are gradually destroyed.

Mechanical damage to the radiator most often occurs during road traffic accidents, collisions with curbs, tree stumps, etc. In addition, the device may be accidentally damaged during car repairs. In any case, the result is the same - leakage from a broken cell.

The size of the hole determines the possibility of repair. If the heat exchanger is not seriously damaged, and the size of the problem area is several square centimeters, you can try to restore it.

There is no other option to repair an aluminum radiator (we’ll figure it out later on how to solder it).

We begin repairing the heat exchanger by draining the coolant and removing the device from the car. Next, it must be rinsed with clean running water and dried. If the damage to the radiator is visible, and you are sure that except for it the device is intact, you can begin preparing the problem area for repair. But if the exact location of the hole (crack) is unknown or approximately known, a more detailed check will be required before soldering the aluminum radiator.

To implement this, we will need a large container of water (you can use a bathtub), a compressor or a pump. The method of searching for the location of the damage is similar to that used to search for the location of a tire puncture. Only here we need to close the lid of the device, as well as all the pipes except one (the thinnest). We immerse the device in water and supply air to it using a compressor or pump. The escaping air bubbles will indicate the exact location of the damage.

How and with what to solder or seal an aluminum radiator

Let's move on to the next stage. Having found the problem area and assessed the scale of future work, it’s time to think about how to prepare an aluminum radiator for repair, how to solder it correctly and what means and tools will be required for this. Let us immediately note that it will not be possible to repair a car heat exchanger using a household soldering iron and rosin. Here you need:

• powerful soldering iron;
• special flux or flux;
• solder of special composition;
• pliers;
• set of files;
• sandpaper;
• acetone.

Let's take a closer look at the main tools and tools.

Soldering iron

As for the soldering iron, it must have a power of at least 250 W. Only with such a tool can the surface of the metal be properly heated so that it can successfully bond with the solder. You can also use soldering irons, which are heated using an open flame. But the best option is a small gas burner (blowtorch) running on a mixture of propane and butane. It will easily heat the area being treated and melt any solder.

Flux

Before soldering the radiator, you will have to take care of the flux. It is this that ensures a reliable connection between the solder and the metal surface being repaired. You can either buy flux or make it yourself. You can purchase it at any store specializing in the sale of radio components. The packages of Russian fluxes intended for soldering aluminum usually have a corresponding inscription. Also, their name may contain the markings F-59A, F-61A, 34A, etc.

How to solder a car radiator at home without buying flux? Is it possible to do it yourself? Yes, you can make flux yourself. It, of course, will not have the same properties as the factory one, but it will cope with its task.

To make it, you only need two ingredients: rosin and iron filings. You can probably find rosin at home, and shavings can be obtained by processing any iron part with a file. All this needs to be mixed in a small fireproof container and heated over a fire.

The resulting mixture is the simplest flux for aluminum.

To obtain a more durable connection between solder and metal, you can make a so-called flux. To do this, you need to mix the following substances in the following proportions:

• potassium chloride – 56%;
• lithium chloride – 23%;
• cryolite – 10%;
• coarse table salt – 7%;
• sodium sulfate – 4%.

The ingredients need to be crushed, mixed and poured into an airtight glass container. Store flux in a place protected from direct sunlight.

Solder

It is not recommended to use tin-lead solders for soldering aluminum. And the point here is not in their composition or strength. The fact is that they are not able to provide adequate anti-corrosion protection for the connection. If you nevertheless decide to use regular solder, then before soldering the aluminum radiator, you will have to take care of purchasing a special varnish, which will subsequently protect the repaired area from corrosion.

But it’s better to immediately buy special solder designed specifically for this metal. Today on sale you can find many compounds for soldering aluminum containing silver, copper, zinc, silicon, etc.

Among the inexpensive Russian-made solders, we can note such mixtures as TsOP-40 (tin - 60%, zinc - 40%) and 34-A (aluminum - 66%, copper - 28%, silicon - 6%).

The percentage of zinc in the solder determines the strength of the connection and corrosion resistance. In other words, the more there is, the better.

How to solder an aluminum car radiator with your own hands

Let's move on to the soldering process. First, the problem area is thoroughly cleaned with a file and sandpaper. If there are lamellas on it, they must be carefully removed with pliers. Next, the repair area is degreased with acetone.

When preparation for soldering is completed, flux can be applied. After this, we begin to warm up the joint. If you use a gas torch or blowtorch, make sure that the flux does not burn out prematurely. It is easier to apply it with a soldering iron. It is enough to dip its working element in the mixture and transfer it to the surface to be treated.

Now it's time to apply the solder. It is better if it is in the form of a rod or wire. Solder is applied to the joint and thoroughly heated with a soldering iron (torch). When it spreads evenly, you need to let it cool, after which it is advisable to apply a second (safety) layer. At the end of the work, the resulting sagging can be removed using sandpaper.

Source: https://FB.ru/article/279020/radiator-alyuminievyiy-kak-zapayat-poshagovaya-instruktsiya-i-rekomendatsii

Is it possible to solder an aluminum car radiator - Metalworker's Guide

Most modern cars are equipped with aluminum radiators. This metal is lightweight, has good anti-corrosion properties, and also has excellent thermal conductivity. In addition, it is significantly cheaper than copper and brass, from which radiators were previously made.

However, aluminum also has a drawback. If a copper (brass) heat exchanger, if damaged, could be repaired without any problems by yourself by soldering the problem area in the usual way, then with an aluminum radiator such a problem will not work. It's all about the chemical properties of this metal. But nothing is impossible. In this article we will look at why an aluminum radiator leaks, how to solder the problem area and what tools will be required for this.

This metal was not chosen by chance for the manufacture of automotive heat exchangers. The fact is that aluminum and most of its alloys have an oxide film that forms a natural barrier that protects against corrosion. This film has high temperature and chemical resistance.

It actively resists conventional fluxes and prevents the application of solder. It can only be destroyed by mechanical surface treatment and special mixtures. This is why it is difficult to restore an aluminum radiator.

We’ll talk a little later about how to solder and, most importantly, how to prepare it for this procedure, but now let’s look at the main reasons why a heat exchanger most often fails.

Main fault

Despite the fragility of the design, the radiator can last for years. Its main enemies are low-quality coolant and foreign objects that can cause mechanical damage.

Antifreeze or antifreeze themselves are not very active substances that can destroy the protective oxide film, and they practically do not react with pure aluminum.

But if the coolant does not meet the required chemical standards, it promotes corrosion processes, as a result of which the honeycomb walls of the device are gradually destroyed.

Mechanical damage to the radiator most often occurs during road traffic accidents, collisions with curbs, tree stumps, etc. In addition, the device may be accidentally damaged during car repairs. In any case, the result is the same - leakage from a broken cell.

The size of the hole determines the possibility of repair. If the heat exchanger is not seriously damaged, and the size of the problem area is several square centimeters, you can try to restore it.

There is no other option to repair an aluminum radiator (we’ll figure it out later on how to solder it).

Where to begin

We begin repairing the heat exchanger by draining the coolant and removing the device from the car. Next, it must be rinsed with clean running water and dried. If the damage to the radiator is visible, and you are sure that except for it the device is intact, you can begin preparing the problem area for repair. But if the exact location of the hole (crack) is unknown or approximately known, a more detailed check will be required before soldering the aluminum radiator.

To implement this, we will need a large container of water (you can use a bathtub), a compressor or a pump. The method of searching for the location of the damage is similar to that used to search for the location of a tire puncture. Only here we need to close the lid of the device, as well as all the pipes except one (the thinnest). We immerse the device in water and supply air to it using a compressor or pump. The escaping air bubbles will indicate the exact location of the damage.

How to solder a radiator at home - aluminum and copper

During engine operation, the cooling system is subjected to various loads. As a result of the action of destructive factors, various damage occurs.

To repair the cooling system, soldering of elements is required. The soldering process is carried out using a certain technology. For high-quality soldering you need special tools and materials.

Our article will tell you how to properly solder a cooling radiator and what materials are needed for this.

Classification of cooling systems

There are several types of engine cooling systems:

• air;
• liquid;
• combined.

The air system uses the flow of outside air to operate. Used in motorized vehicles with low power engines.

In a liquid system, a heated engine is cooled with a special coolant. Most modern car engines are equipped with such a cooling system.

The combined system combines the operation of liquid and air systems. Used to operate high-power power plants. Widely used at energy sector enterprises.

Why do you need a cooling radiator?

A radiator is a device for cooling an engine. This device is the main element of the cooling system.

The cooling system consists of upper and lower circuits. The contours are steel pipes of rectangular or circular cross-section. They are designed for coolant input and output.

There is a metal grill between the contours. The lattice cells are in the form of thin plates or tubes. The grate is designed for uniform distribution and cooling of the coolant.

Various damage to the metal grill requires soldering of the radiator plates and tubes.

How does an engine cooling system work?

Coolant from the engine enters the upper circuit of the system. When entering the system, the coolant has a high temperature. The hot coolant descends through the grid cells into the lower circuit.

On the way from the upper circuit to the lower coolant it cools down. Cooling occurs as a result of the passage of cooled air through the grille. The cooled liquid from the lower circuit is supplied to the engine. A fan is used to force the engine to cool.

Water or a mixture of water and ethylene glycol (antifreeze) is used as a coolant. Such mixtures do not freeze even at a temperature of -40° C. At subzero outside temperatures, antifreeze turns into a thick mass. The gel-like mass does not destroy the cooling system when frozen.

The use of antifreeze allows the use of a liquid cooling system in winter.

Causes of destruction of a car radiator

During operation, elements of the cooling system may receive various damage. There are the following causes of damage:

1. mechanical;
2. chemical;
3. thermal.

Mechanical reasons are caused by the impact on the grille during an accident, road stones, and collisions with various obstacles.

Chemical malfunctions are caused by the effects of corrosive processes on the internal and external surfaces of the radiator.

Thermal malfunctions occur as a result of scale formation on the internal walls of the device.

As a result of leaks, partial or complete loss of coolant occurs. Reducing the amount of coolant leads to overheating of the units and a high probability of engine failure.

To prevent malfunctions in the operation of the cooling system, soldering of radiators is used.

How to find a leak in the cooling system

Cooling system malfunctions are identified during vehicle maintenance and repair.

To identify damage, the radiator is removed from its installation site. Through a special hole, the coolant is drained into a pre-prepared container. To drain the coolant, the device is turned over and shaken several times.

There are two main methods used to detect leaks:

• visual;
• instrumental.

The visual method consists of identifying damage during inspection of units. The location of the leak is determined by characteristic marks on the grille or other elements of the cooling system.

The instrumental method is carried out using various diagnostic equipment. When a leak is detected, the equipment emits a light and sound signal.

Repair of aluminum and copper radiators

The materials used to make most devices are copper and aluminum. These metals are characterized by high thermal conductivity and resistance to high temperatures.

Features of copper soldering

Copper radiators have a characteristic red-pink hue. Copper products are easy to solder. The simplicity of the process allows you to repair copper products at home.

The disadvantage of copper is its susceptibility to corrosion and high cost.

Aluminum has high corrosion resistance and low weight. Aluminum products have a silver color.

The chemical properties of aluminum make it difficult to solder products made from this metal. Repairing aluminum radiators at home is very difficult.

Soldering materials and tools

For soldering automotive cooling systems, a standard set of tools and materials is used.

How to properly solder a copper radiator

To carry out the work you will need the following tools and materials:

1. Soldering tool.
2. Alloy for soldering (solder).
3. Solvent (acetone).
4. Flux or rosin.
5. Pliers.
6. Brush.
7. Wire brush.
8. Fine-grit sandpaper.

An electric soldering iron with a power of at least 100 W or a gas torch is used as a soldering tool.

To solder a copper radiator with your own hands, two types of soldering irons are used. To repair large-area damage, soldering irons with a wide tip are used. For sealing small faults - with a narrow tip.

The pliers are designed to remove damaged grille elements.

The solvent is necessary to degrease the surface.

A wire brush is needed to roughly clean the grate from dirt and rust.

Sandpaper is required to clean the damaged area from metal dust and melting products.

The brush is intended for applying rosin or flux. These materials are used for better adhesion of solder to the metal surface.

For soldering copper radiators, tin-lead solders of the POS-60 and POS-61 brands are used.

How to properly solder an aluminum radiator

When asked by car enthusiasts whether it is possible to solder an aluminum cooling radiator with your own hands, experts answer with a positive answer.

To solder aluminum you will need:

1. Soldering tool.
2. Alloy for soldering (solder).
3. Solvent (acetone).
4. Flux or rosin.
5. Iron filings.
6. Fireproof container (crucible).
7. Pliers.
8. Brush.
9. Wire brush.
10. Fine-grit sandpaper.

The following types of solder are used for soldering aluminum products:

• for repairing small cracks - tin plus lead (grade POS-40);
• for repairing large cracks - tin plus bismuth (grades POSV-33 and POSV-50).

To prepare the flux you will need:

1. Rosin – 2 parts.
2. Iron filings – 1 part.

Rosin and sawdust are thoroughly mixed. The resulting composition is placed in a crucible. The container with flux is heated over an open fire. After cooling, the flux is ready for use.

To prepare iron filings, use a hacksaw with a fine tooth. Iron filings are designed to destroy the aluminum oxide film when applying solder to metal.

Principle and technological features of the soldering process

The soldering process depends on the material of the radiator. Copper lends itself well to soldering. There are no difficulties in the process of working with copper.

The difference between aluminum soldering lies in the peculiarities of its chemical properties. When interacting with oxygen, a heat-resistant oxide film appears on the metal surface. Therefore, when soldering aluminum, a number of additional operations are used to remove the oxide film. Removing the film helps to firmly bond the solder to the damaged surface.

Before soldering a copper or aluminum radiator, clean the internal surface of the device from scale. Using a metal brush, remove dirt from its outer surface.

Cleaning the radiator from scale

Special cleaning agents are used to remove scale. At home, use a solution of citric or acetic acid. The cleaning solution is prepared at the rate of 1-2 tablespoons of acid per 500 ml of water.

To remove scale, a cleaning solution is poured into the radiator. After a few minutes of waiting, the device is shaken and the solution is removed. If necessary, the procedure is repeated several times.

To increase the cleaning effect, the grille is heated from the outside using a gas burner.

Cleaning the radiator from dirt

To remove dirt from the outer surface, use a wire brush. Contamination from petroleum products is removed using special cleaning products.

After cleaning, the radiator is rinsed with clean water and thoroughly dried in the open air. When working indoors, use a jet of hot air to blow the installation.

How to properly solder a copper or aluminum radiator

After cleaning from scale and dirt, perform the following operations:

• Cleaning the damaged area with sandpaper.
• Degreasing with acetone.
• Heating the soldering area with an open flame.
• Applying a layer of rosin
• Treating the soldering area with flux.
• Laying and melting solder.

Heating of the damaged area is carried out with extreme caution. If the heat is insufficient, the solder will not stick. When overheated, soldering acid quickly evaporates. With sufficient heating, boiling and gradual evaporation of soldering acid occurs.

Solder is applied in a thick layer to the damaged area. Using a soldering iron in a circular motion, carefully rub the mixture into the surface.

If the solder does not stick to the surface, the soldering area is re-cleaned and the soldering procedure is repeated.

The functionality of the device is checked by repeated immersion in water.

How to solder a cooling radiator at home

To detect the location of a leak at home, they act in a different way. Close all inlets and outlets in the pipes with plugs made of waterproofing materials.

Folk craftsmen came up with the idea of ​​putting pieces of bicycle inner tubes on the outlets of the pipes. To protect against the passage of air, the rubber is tied in a knot. A piece of camera with a nipple is put on one exit. A bicycle pump is used to pump air. The location of the leak is determined by the location of the appearance of air bubbles.

The further course of work is carried out according to the well-known scheme:

1. The cleaned grate is placed on a flat horizontal surface.
2. Using a brush, lubricate the heated area with soldering acid.
3. Solder is applied with a soldering iron.
4. Distribute solder evenly over the damaged surface. The work is carried out until the damage is completely filled with solder.

After soldering, the device is tested by immersion in a container of water.

If there is a large amount of damage, you need to contact a specialized workshop or think about buying a new radiator.

Source: http://pikucha.ru/otoplenie/radiatory/zapayat-radiator-oxlazhdeniya.html

How to solder an aluminum radiator: 3 ways to solve the problem

It is difficult to eliminate defects in aluminum radiators, but it is possible even without special equipment

Soldering aluminum radiators when performing repair work is one of the most complex and critical processes. As a rule, both in the case of repairing heating devices and when restoring car radiators, the solution to this problem is entrusted to professionals.

But if you have knowledge, skills and minimal dexterity, it is quite possible to solder an aluminum device with high quality. What is required for this and how the work should be done, I will now tell you.

The choice of aluminum for the manufacture of various radiators is not accidental: this metal has an optimal combination of low weight, strength and excellent thermal conductivity. Thanks to this, plate structures with a large total area can be made from aluminum, and they will provide excellent heat transfer.

But the material also has a drawback, which is the difficulty of repairing any radiators if damaged:

A film of oxides appears on any aluminum products

1. Aluminum is a chemically active material. Because of this, the metal surface oxidizes very quickly, becoming covered with a layer of oxide film.
2. The oxide film becomes an obstacle to soldering two aluminum products. For maximum strength, it is necessary to achieve direct metal-to-metal contact, but when heated, a thin layer of oxides inevitably forms between them.

The oxide layer protects against corrosion - this is true for both copper and aluminum

On the other hand, if it were not for the film, then the corrosion of aluminum in air would be extremely active. The same is typical, for example, for a copper radiator: the surface layer of oxides plays the role of insulation, impermeable to oxygen.

1. To effectively solder an aluminum radiator, you need to get rid of oxides on its surface. For this purpose, special compounds are used - fluxes. The use of fluxes based on cadmium, bismuth or zinc allows you to clean the surface of the material, reduce the stress on the surfaces during connection and improve the adhesion of the metal to the solder.

Oxides are removed using special fluxes

The price of high-quality fluxes for soldering this metal can be quite high (for example, Castolin Alutin 51L - about 300 rubles for 25 g). That is why, when repairing radiators at home, they use homemade compounds - the so-called fluxes.

Even such a small hole will not be easy to repair.

In any case, when soldering, the main task is to isolate the treated area from contact with oxygen. This is achieved in a variety of ways.

An alternative technique - sealing the defect by cold welding - can only be considered as a temporary measure. Still, such compositions cannot withstand operational loads, and sooner or later their strength decreases.

Method 1. Iron-rosin flux

So, how to solder a damaged aluminum radiator? The easiest way is to use rosin-based flux. The instructions will be as follows:

1. Preparation. We clean the area to be treated, removing any remaining paint and dirt, then sand the metal with an abrasive and degrease it with a solvent. The more carefully we carry out all this work, the more effective the repair will be.

The basis of the flux is crushed rosin

1. Preparation of flux. We melt rosin in a metal crucible, gradually heating the container and stirring the melting substance. Add iron filings in small portions (1 part to 2 parts rosin) and stir until the mixture is completely homogeneous.

Sawdust in the soldering mixture acts as an abrasive

1. Surface treatment. We cover the area to be repaired with a thin layer of molten iron-rosin flux. The fewer missed sections, the higher the quality of the repair.

It is advisable to carry out both work with fluxes and soldering under a hood. If this is not possible, then you need to work in a well-ventilated area.

Adding propoy under a layer of flux allows you to protect the surface from oxidation

1. Soldering. We collect a small amount of solder on the soldering iron, and then apply it in a circular motion to the aluminum under a layer of flux. Iron filings act as an abrasive: they clean off oxides, ensuring a bond between solder and aluminum. Melted rosin allows you to minimize the access of oxygen, so secondary oxidation does not occur.

The main disadvantage of this method of soldering aluminum is its complexity. It is almost impossible to treat such large damage, since the flux hardens quickly and the quality of the repair is reduced.

The sealed area should look something like this

Method 2. Homemade flux

When repairing fairly large damage to aluminum radiators with your own hands, you can use special compounds - flux. In this case, the work is performed like this:

1. Preparation. We prepare the defect site according to the scheme described in the previous section, cleaning and degreasing the metal.

The area with the defect must be thoroughly cleaned and degreased.

1. Fluid components. Sodium sulfate (4%), potassium chloride (56%), lithium chloride (23%), cryolite (10%) and table salt (75%) are individually ground in a mortar almost into powder. After this, pour the materials into the crucible and mix until a homogeneous powder is obtained.

The components of homemade flux melt in such a crucible.

Ground components are hygroscopic (absorb moisture from the air). Therefore, they need to be stored in dark glass containers with ground stoppers, avoiding overheating and direct sunlight.

1. Preparation of the floodplain . Pour the dry ingredients into the crucible and melt until smooth, stirring gently.
2. Soldering. We apply a thin layer of flux to the surface, which is preheated using a gas burner. After this, we solder the damaged area using tin-lead solder with the addition of bismuth.

Eliminating a defect using flux and solder

Method 3. Low-temperature solder with sizing

It is quite difficult to solder such a leak. But it's real!

A car radiator differs from heating radiators primarily in the configuration of the tanks. When troubleshooting a problem, you have to solder small thin-walled tubes and plates, so the methods described above will not always be applicable.

Self-fluxing low-melting solder rods

An alternative is to use aluminum solder rods with a low melting point. An example of repairing a radiator is given in the table:

Illustration	Work stage
Cleaning up the area. Using sandpaper or a special attachment on a drill/screwdriver, we clean the aluminum, removing the film of oxides.
Degreasing. We treat the area with a solvent, removing organic contaminants and oxide residues.
Crimping damage. Using small pliers, we crimp the damaged area, reducing the area of ​​the hole. This is done to facilitate the soldering process.
Soldering. Using a gas burner, we warm up the area. After this, we introduce a rod of solder with a low melting point into the flame and rub it over the damage. With each pass, solder particles will be deposited into the hole and onto the surfaces around it, gradually eliminating the defect.
Additional sealing. After soldering is complete, apply high-temperature aluminum adhesive over the repaired area. When polymerized, this material will close all micropores, which will significantly increase the reliability of the repair.

After soldering and treating with glue, the radiator sections look like in the photo

Conclusion

Soldering an aluminum radiator requires from the master not only responsibility and dexterity, but also certain knowledge, as well as strict adherence to technology. The video in this article will help you understand the main tricks of the described technique, and you can get advice on performing complex operations by asking a question in the comments.

Source: https://otoplenie-gid.ru/elementy/radiatori/764-kak-zapayat-alyuminievyj-radiator