How to check the quality of antifreeze, so as not to be in a dangerous situation later

No internal combustion engine will last long without timely cooling. Most motors are liquid cooled. But how do you know that the antifreeze in the car has exhausted its resource and needs to be replaced? Let's try to figure it out.

Why antifreeze needs to be changed

There are many moving parts in an engine that get hot during operation. Heat must be removed from them in a timely manner. For this, a so-called shirt is provided in modern motors. This is a system of channels through which antifreeze circulates, removing heat.

Modern industry offers car owners a wide range of antifreezes.

Over time, its properties change, and here's why:

• foreign impurities, dirt, the smallest metal particles from the shirt can get into the antifreeze, which will inevitably lead to a change in the chemical composition of the liquid and to a deterioration in its cooling properties;
• during operation, antifreeze can heat up to critical temperatures and gradually evaporate. If you do not replenish its supply in a timely manner, the motor may be left without cooling.

Consequences of untimely replacement of antifreeze

If the driver forgot to change the coolant, there are two options:

• motor overheating. The engine starts to fail, the revolutions float, power dips occur;
• motor jamming. If the driver ignored the signs listed in the previous paragraph, the engine will jam. This is accompanied by serious damage, the elimination of which will require major repairs. But even he does not always help out. In most situations, it is more profitable for a driver to sell a faulty car than to repair it.

Coolant replacement interval

The intervals between antifreeze replacements depend both on the brand of the car and its technical characteristics, and on the cooler itself. In the most general case, it is recommended to change the fluid every 3 years. This will prevent corrosion in the motor. But manufacturers of popular cars have their own opinion on this matter:

• on Ford cars, antifreeze is changed every 10 years or every 240 thousand kilometers;
• GM, Volkswagen, Renault and Mazda do not need a new cooler for the life of the vehicle;
• Mercedes requires new antifreeze every 6 years;
• BMWs are replaced every 5 years;
• in VAZ cars, the fluid changes every 75 thousand kilometers.

Classification of antifreezes and manufacturer's advice

Today, coolants are divided into several classes, each of which has its own characteristics:

• G11. The basis of this class of antifreeze is ethylene glycol. They also have special additives, but in minimal quantities. Almost all companies producing this class of antifreeze advise changing them every 2 years. This allows you to protect the motor from corrosion as much as possible;
  

  Arctic is the typical and most popular representative of the G11 class.
• G12. This is a class of coolants without nitrites. They are also based on ethylene glycol, but the degree of its purification is much higher than that of G11. Manufacturers advise changing the fluid every 3 years and using it in motors that experience increased loads. Therefore, the G12 is especially popular with truck drivers;
  

  Antifreeze G12 Sputnik is found on domestic shelves everywhere
• G12+. The basis of antifreeze is polypropylene glycol with a package of anti-corrosion additives. It is non-toxic, decomposes quickly and isolates corroded areas well. Recommended for use in motors with aluminum and cast iron parts. Changes every 6 years;
  

  Felix belongs to the G12+ antifreeze family and has an affordable price.
• G13. Antifreezes of hybrid type, on a carboxylate-silicate basis. Recommended for all types of engines. They have a complex complex of anti-corrosion additives, therefore they are the most expensive. They change every 10 years.
  

  Specialized antifreeze G13 VAG for Volkswagen cars

Replacing antifreeze depending on the mileage of the car

Each car manufacturer regulates the timing of coolant replacement. But drivers use cars at different rates, so they cover different distances. So, the manufacturer’s official recommendations are always adjusted for the car’s mileage:

• domestic antifreezes and G11 antifreezes change every 30-35 thousand kilometers;
• fluids of classes G12 and above change every 45–55 thousand kilometers.

The specified mileage values ​​\uXNUMXb\uXNUMXbcan be considered critical, since it is after them that the chemical properties of antifreeze begin to gradually change.

Strip test on a worn motor

Many car owners buy cars from their hands. The engines in such cars are worn out, often very much, which the seller, as a rule, is silent about. Therefore, the first thing a new owner should do is check the quality of antifreeze in a worn out engine. The easiest way to do this is to use a set of special indicator strips, which can be purchased at any parts store.

A set of indicator strips with a scale can be purchased at any auto parts store.

The driver opens the tank, lowers the strip there, and then compares its color with a special scale that comes with the kit. General rule: the darker the strip, the worse the antifreeze.

Video: checking antifreeze with strips

Antifreeze strip test

Visual assessment of antifreeze

Sometimes the poor quality of the coolant is visible to the naked eye. Antifreeze may lose its original color and turn white. Sometimes it becomes cloudy. It may also take on a brownish color. This means that it contains too much rust, and corrosion of parts has begun in the engine. Finally, foam can form in the expansion tank, and a thick layer of hard metal chips forms at the bottom.

If foam appears in the tank, the antifreeze must be changed urgently.

This suggests that the engine parts began to break down and the antifreeze must be urgently replaced, after flushing the engine.

Boil test

If there is any doubt about the quality of antifreeze, it can be tested by boiling.

1. A little antifreeze is poured into a metal bowl and heated on gas until it boils.
   

   You can use a clean tin can to test antifreeze by boiling.
2. Attention should be paid not to the boiling point, but to the smell of the liquid. If there is a distinct smell of ammonia in the air, antifreeze cannot be used.
3. The presence of sediment at the bottom of the dishes is also controlled. High-quality antifreeze does not give it. Solid particles of copper sulphate usually precipitate. When they enter the engine, they will settle on all rubbing surfaces, which will inevitably lead to overheating.

Freeze test

Another method for detecting counterfeit antifreeze.

1. Fill an empty plastic bottle with 100 ml of coolant.
2. The air from the bottle should be released by slightly crushing it and tightening the cork (if the antifreeze turns out to be falsified, it will not burst the bottle when it freezes).
3. The crumpled bottle is placed in a freezer at -35°C.
4. After 2 hours, the bottle is removed. If during this time the antifreeze only slightly crystallized or remained fluid, it can be used. And if there is ice in the bottle, it means that the base of the cooler is not ethylene glycol with additives, but water. And it is absolutely impossible to fill this counterfeit into the engine.
   

   Counterfeit antifreeze that turned to ice after a couple of hours in the freezer

So, any motorist can check the quality of antifreeze in the engine, since there are many methods for this. The main thing is to use the coolant of the class recommended by the manufacturer. And when using it, be sure to make an adjustment for the mileage of the car.