How to check antifreeze
Content
Question how to check antifreeze, is relevant not only during its long-term operation in the cooling system, but, first of all, when buying a new coolant. After all, the use of fake antifreeze or one that has lost its properties will negatively affect all components of the cooling system.
The parameters that should be measured for antifreeze are its general condition, freezing point, boiling point. This can be done at home using heat, a multimeter and a hydrometer. When the check is carried out in the cooling system itself, it is important to make sure that there is no oil and gases in the antifreeze, that there is no leakage, as well as its level in the expansion tank. How to perform all these checks correctly and quickly read in the article.
How to check the level of antifreeze
Filling / topping up antifreeze, as well as monitoring its level in the system, is carried out using an expansion tank. In most cases, there are MAX and MIN marks on the tank body (sometimes FULL and LOW), which indicate the maximum and minimum coolant levels. But sometimes there is only MAX, less often there are no marks on the tank at all, or it is located so inconveniently that it is impossible to visually assess the amount of liquid, not to mention its condition.
For those who do not know antifreeze, they check for hot or cold, the answer is - only cold! This is due to two factors. The first is that antifreeze expands when heated and its level will appear higher. The second - checking for hot is simply dangerous, because you can burn yourself.
Minimum and maximum risks on the tank
Ideally, the antifreeze level should be about 1-2 cm below the maximum mark. If there are no marks on the tank, then the expansion tank is filled with antifreeze by about half the volume. Well, the check, respectively, must be done visually. If the tank is dark, use a stick or a long thin object.
If the antifreeze does not leak anywhere, then its level does not change for a long time, since it circulates in a sealed system and cannot evaporate anywhere. A low level may indicate a leak and it is not necessarily visible, so the liquid can go into the cylinders.
When the check showed that the level is higher than necessary, then this should also be paid attention to, especially if it gradually grows or gases (bubbles) come out of the expansion tank or radiator. Most often this indicates a broken cylinder head gasket. As a result, the level rises due to airing or oil ingress. You can check the oil in antifreeze visually, by touching the coolant. The gases in antifreeze are checked through the sense of smell (the smell of exhaust gases), as well as by drilling fluid in the tank. With an increase in speed, the number of bubbles in the expansion tank will increase. in order to find out if there are gases in antifreeze, methods are used to check the integrity of the cylinder head gasket.
Most often, owners of Hyundai Solaris and Kia Rio cars, as well as other cars of these brands, have difficulties with checking the level of antifreeze. This is because their tank is also located in a very inconvenient place, like its design itself. Therefore, in order to find out what level of coolant in the system, you will have to take a flashlight and highlight it behind the radiator. The reservoir is located on the right side of the fan shroud, in front of the engine compartment. On the side of the tank there is a scale with the letters F and L. In addition, you can also see the level in the radiator by unscrewing its cap. It is located next to the expansion tank (3 pipes converge to it).
How to check antifreeze for quality
A general check of antifreeze for quality and further suitability for use in the radiator, and the system as a whole, can be done using an electronic multimeter, litmus paper, by smell and the presence of sediment.
Checking antifreeze with a multimeter
To check it in the cooling system, you need to set the DC voltage measurement scale in the range of 50 ... 300 mV. After turning on the multimeter, one of its probes must be lowered into the neck of the radiator or expansion tank so that it reaches the antifreeze. Attach the other probe to any cleaned metal surface on the internal combustion engine ("mass"). Such a check of antifreeze in a car for quality can give the following results:
Checking antifreeze with a multimeter
- Less than 150mV. This is a clean, completely serviceable antifreeze. The lower the value, the better.
- Range 150...300 mV. Antifreeze needs to be changed, because it is already dirty, it has developed protective, lubricating and anti-corrosion additives.
- Over 300 mV. Antifreeze is definitely a replacement, and the sooner the better!
This at-home antifreeze test method is versatile and can be used to analyze new and used coolant before determining its boiling or freezing point. Since over time, antifreeze loses its initial characteristics.
Touch and smell test
New or used antifreeze can simply be rubbed between the index finger and thumb. More or less high-quality antifreeze will feel like soapy water to the touch. If the antifreeze is just like tinted water, it is either a fake or a coolant that has already lost its properties. After such an experiment, be sure to wash your hands!
you can also warm up the antifreeze. If during the heating process you feel a distinct smell of ammonia, the antifreeze is fake or of very low quality. And when a precipitate forms in the antifreeze during heating, then you should categorically refuse to use it.
Check antifreeze pH
Testing acidity with litmus paper
If a litmus test is available to you, then it can also be used to indirectly check the condition of antifreeze. To do this, place the test strip in liquid and wait for the result of the reaction. Assessing the color of the paper, you will find out the pH factor. Ideally, the paper should not be blue or red. The normal pH value for antifreeze is considered to be 7 ... 9.
How to check antifreeze for freezing
Checking antifreeze with a machine hydrometer
It is impossible to check the temperature of antifreeze at which it will freeze in a conventional freezer, because it will not be possible to cool the liquid in it below -21 ° C. The freezing point of antifreeze is calculated from its density. Accordingly, the lower the density of the antifreeze (up to about 1,086 g / cm³), the lower the freezing point. Density, and accordingly, the freezing point is measured using a hydrometer. They are of two types - household (medical) and special machine. Household hydrometers are usually submersible. On their lateral surface there is a scale with the corresponding density values (usually in g / cm³). Which is better to choose a hydrometer for checking antifreeze, see here.
How to check antifreeze with a hydrometer
A machine hydrometer is a plastic bottle (or glass tube) with a rubber hose and bulb attached to the neck. With it, you can take samples of antifreeze directly from the radiator. On the side of the bottle there is a scale with nominal information about the freezing point. Density values in the temperature value can be viewed in the table.
| Density of antifreeze, g/cm³ | Freezing point of antifreeze, °C |
|---|---|
| 1,115 | -12 |
| 1,113 | -15 |
| 1,112 | -17 |
| 1,111 | -20 |
| 1,110 | -22 |
| 1,109 | -27 |
| 1,106 | -29 |
| 1,099 | -48 |
| 1,093 | -58 |
| 1,086 | -75 |
| 1,079 | -55 |
| 1,073 | -42 |
| 1,068 | -34 |
| 1,057 | -24 |
| 1,043 | -15 |
Antifreeze boil test
You can check the boiling point using an electronic thermometer capable of showing temperatures over 120 degrees Celsius. The essence of the experiment is very simple. The task is to heat the liquid in a vessel on an electric stove and fix the temperature at which it begins to boil.
The boiling point for antifreeze is very important for the following reasons:
Antifreeze boil and burn test
- When boiling, the action of additives in the coolant is reduced.
- With boiling and a further increase in temperature, the pressure in the enclosed space increases, which can damage the elements of the cooling system.
so, the lower the boiling point of antifreeze, the worse it is for the internal combustion engine, since the efficiency of its cooling decreases, and in addition, the pressure in the cooling system increases, which can lead to damage to its elements.
For all old antifreezes, the boiling point decreases during operation, so it is important to check it not only when buying a new fluid, but also periodically with coolants after a year or more of operation. Such a check of antifreeze will help determine its condition and suitability for further use.
Checking antifreeze for combustion
When buying a new antifreeze, it is important to check it for burning evaporating fumes. High-quality liquid should not ignite when boiled. In a fake coolant, alcohols are added to increase the freezing point, which evaporate at critically high temperatures, and such vapors can literally ignite in the pipes, radiator and other elements of the system.
The experiment is easy. It is enough, when checking the boiling point, to try to set fire to the antifreeze vapor evaporating from the flask when it boils. To do this, it is better to use a vessel with a narrow neck. If they burn, the antifreeze is of poor quality, but if they don’t burn, then it passed this test, which means that there is no danger of fire and rupture of the pipes.
Antifreeze Leak Check
You can check where antifreeze flows on any car by doing one of three methods:
Cover for pressurizing the system
- visual inspection. The simplest method, but not very efficient, as it can only find significant leaks.
- Fluid pressure test. To perform it, the antifreeze is completely drained from the cooling system, and instead water is pumped under pressure. Excessive pressure will most likely show where the leak was.
- Searching with ultraviolet light. Many modern antifreezes contain fluorescent additives (or you can add them to the liquid yourself), which become visible when you shine an ultraviolet flashlight on them. Therefore, at the slightest leak, you will see a place on a luminous trail.
At home, there is one proven life hack on how to check where antifreeze flows using a machine compressor. It consists in taking an old similar plug from the expansion tank, drilling it and inserting the nipple from the wheel (securing it tightly). then put the cap on the expansion tank and use an air compressor to create excess pressure in the system, but NOT MORE THAN 2 atmospheres! A very effective method!
Hack and predictor Aviator
At home or garage conditions, you can easily check the main operational parameters of any antifreeze. Moreover, with improvised means. The main thing is to check the new antifreeze if you suspect its poor quality, and also check the old antifreeze, which has been poured into the cooling system for a long time. And do not forget to change the coolant according to the regulations!
