Advice from experienced car owners on how to flush the engine cooling system from rust and scale

Flushing the engine cooling system is a mandatory procedure for every motorist. The scale, dirt, and rust remaining inside ultimately clog the radiator channels, pump, and pipes.

To prevent this, it is important to determine the moment when the structure needs cleaning and choose the appropriate product. To remove deposits, both traditional and special cleaners are used.

In this article we will tell you how to flush the engine cooling system from rust and scale at home.

When is flushing necessary?

Internal cleaning is recommended at least once a year. It is best to do this after winter is over. A light indicator with a picture of a radiator helps determine the exact time. In addition, there are other signs by which one can judge the need for cleansing.

These include:

1. Systematic engine overheating and failures when starting it.
2. Inertia of the rheostat, inhibited response to its signal.
3. High temperature readings from the coolant sensor.
4. Interruptions in the operation of the pump, signaling problems in the system.
5. Change in the color and smell of the refrigerant in the expansion tank.

What do you need to know before the procedure?

Flushing the cooling system is a serious procedure that requires car maintenance skills.Improper cleaning can lead to problems, so before starting the procedure you need to familiarize yourself not only with the structure of the mechanism, but also with the cleaning rules.

For example, if the air conditioner condenser is made of aluminum, then the use of citric acid may cause thinning of its walls. At the same time, cast iron and steel parts completely retain their integrity.

The design of the cooling system should also be taken into account. Thin channels can be damaged if, during cleaning, fragments of a thick film of old antifreeze, pieces of rust or scale come off. If the channel is clogged, the engine will overheat.

To avoid problems that arise during radical cleaning, it is recommended to carry out prevention, use the original antifreeze composition and change it on time.

Products for home use

With proper care and preventive maintenance, cleaning the cooling system is not difficult. Before starting the procedure, you need to prepare it:

1. The engine is cooled if it was running before.
2. Place a container for old antifreeze under the drain.
3. Unscrew the plugs from the bottom of the radiator and cylinders.
4. Wait until the liquid is completely drained from the system.
5. The drain plugs are screwed back in.
6. Fill the expansion tank with cleaner.

Distilled water

If over the past years the car has been kept in order and preventive washes have been carried out, then the use of distilled water is considered sufficient.

It is poured into an empty expansion tank. The amount of distillate must correspond to the volume of the container. After this, start the engine for 10-25 minutes.

For best results, it is recommended to take a test ride. After turning off the car, allow time for cooling and drain the water from the tank.

Lemon acid

This product helps to cope with a small degree of contamination. To prepare the working solution, citric acid is dissolved in water..

The standard proportion is 30-40 g per 1 liter. To enhance the effect, prepare a more concentrated solution, increasing the dose of powder to 80-100 g. The optimal pH value of the lemon reagent is 3.

After the cleaner is poured into the tank, turn on the engine and warm it up for 15-25 minutes. Leave the reagent in the system for 5-12 hours. When draining the solution, visually check the degree of contamination. If necessary, the cleaning procedure is duplicated.

You can learn more about the use of citric acid in the fight against rust. Here.

The video will show you how to flush the cooling system with citric acid:

Vinegar

For washing, use vinegar with a concentration of 9%. For 5 liters of water you need a glass of acid (250 ml). This cleaner is used by analogy with citric acid.

The acetic reagent is poured into a container from which the antifreeze has previously been drained. Fill the tank with the prepared solution, start the engine for 20-30 minutes. The acetic liquid is drained after 8-12 hours. Flush the system with distillate and fill it with new refrigerant.

More information about the use of vinegar in the fight against rust can be found in this articles.

Milk serum

For work, use store-bought or homemade serum.. In the latter case, the liquid must be filtered through several layers of gauze so that no curdled inclusions remain in it. The serum should not be diluted with water before use.

Soda

The washing solution is prepared from soda ash (8-10%) and caustic (3%) soda.

The powder is diluted with water, its amount in the solution should be 85-90%. After filling the tank with soda reagent, the car is driven 50-100 km. Then the cleaner is drained and the distillate is passed through several times.

The soda solution should not be left in the cooling system for a long time. The maximum time is a day.

Cola

The drink contains orthophosphoric acid, which dissolves salt deposits and rust. However, the method is considered not the safest, since acid has a negative effect on rubber pipes, and sugar has a negative effect on metal surfaces.

If the choice is still made on this purifier, then carbon dioxide is first removed from the drink. After filling, the engine is left in working condition for a maximum of 15-20 minutes. After removing the Coca-Cola, the system is cleaned with distilled water. Read more about using Coca-Cola against rust. here.

Special formulations

Ready-made chemical cleaners are divided into four groups:

• neutral,
• acidic,
• alkaline,
• combined.

To select a suitable liquid, it is necessary to determine the degree of contamination of the cooling structure and the type of deposits.

Our range of effective chemical washes includes:

1. LAVR. Russian-made foam decarbonizer is intended for trucks and passenger cars. For rinsing purposes, first fill in liquid from bottle No. 1 and water. Start the engine for a quarter of an hour. Drain the first reagent and fill in liquid from bottle No. 2, adding water. Leave the car again with the engine running for 15-20 minutes. Flush the system with distillate two or three times. A set consisting of two bottles costs an average of 500 rubles.
2. Hi-Gear Radiator Flush. Product manufactured in the USA. Suitable for passenger cars. There are no acids in the formula, so the cleaner is safe for rubber elements.

   The product is poured into the tank with a cold engine, after mixing the entire volume of the bottle with 4-5 liters of water. Start the engine for 7 minutes at a speed of 1500–2500 rpm.

   Then wait until the engine cools down, drain the chemical and wash it with distillate. The average price of a bottle is 350 rubles.

3. LIQUI MOLY Kuhler-Reiniger. A German remedy classified as neutral. Ideal for cleaning rust, oils, emulsions. The reagent is added to the coolant at the rate of 300 ml per 10 liters of refrigerant. Start the car and keep it idling for up to half an hour. After switching off, if necessary, leave for another 3 hours. Then the contents are drained and washed with distillate.A bottle sells for an average of 460 rubles.

Recommendations

When cleaning the cooling system, it is recommended to follow the instructions included with the selected cleaner. It is also useful to remember some important points:

• after cleaning, the system is thoroughly washed with distilled water;
• if there is heavy contamination with rust and scale, the cleaning should be repeated;
• if the cleaner is poured into a still warm system, then it should also be warm;
• When choosing a chemical reagent, the scope of its application should be taken into account.

All the most useful and important information about methods and techniques for removing rust from a car - Here.

Conclusion

Both folk and special anti-rust and scale products help flush the engine cooling system.

To reduce the frequency of cleaning, it is recommended to change the refrigerant in a timely manner in the system and carry out preventive measures. In this case, the cooling system will work properly and will not create problems with engine overheating.