Antifreeze is a liquid used to cool a car engine. Its special property is resistance to low temperatures. A characteristic indicator of the suitability of antifreeze for use is density, due to a decrease in which it loses its frost resistance.
How to check antifreeze using a hydrometer
The density of antifreeze is checked using a special device - a hydrometer. Currently, devices are produced that have two scales - for determining the density of the electrolyte and for determining the freezing point of the coolant. To check the density of the antifreeze, open the hood of the car, unscrew the radiator cap. Press down on the hydrometer balloon to release the air and place the device in the radiator. Lower the bulb, this will fill the flask of the device with liquid.
Look at the hydrometer scale: the line of contact of the liquid with the hydrometer rod will correspond to the freezing point of the antifreeze. If the antifreeze has a density that allows it to be used in frost, the scale will be green (30-40 ° C), if it has partially lost its frost resistance, the scale will be red (20-30 ° C), with a strong loss of frost resistance, it will be yellow (10-20 ° C), if the antifreeze is unsuitable to use - the scale will be blue (0-10 ° C). Press on the hydrometer balloon and pour the antifreeze back into the radiator. If the density of the antifreeze is lowered, the concentrate should be added to it: add "Antifreeze A65" to "Tosol A40". At increased density, distilled water is added to the coolant.
After use, the device must be washed with running water and dried. Do not use the same hydrometer to determine the density of electrolyte and antifreeze.
Checking the density of antifreeze when buying
When buying, the density of antifreeze is determined in order to identify a fake, the simplest of which is blue water. The seller can offer to check the coolant using a special hydrometer: high-quality antifreeze has a density of 1.073-1.079 g / cm3. However, such a check may yield nothing. The counterfeit may contain triethylene glycol, diethylene glycol or propylene glycol, which are much cheaper than ethylene glycol, but with these components, the density will correspond to the norm. There are cases when table salt was added to the water to achieve the required parameters.
In order not to run into a fake, you need to purchase antifreeze only in large stores.
It is better to check the quality of antifreeze when buying with the help of a litmus test, this method is the most reliable. Dip a piece of paper into antifreeze and compare the result with the scale to determine the pH of the solution. If the paper turns pink (pH = 1-5), the solution contains a lot of acid and is a fake, if the paper turns blue (pH = 10-13), there is a lot of alkali in the solution, which indicates a fake or poor-quality antifreeze. The green color of the paper (pH = 7-9) indicates that the antifreeze can be of high quality.
