{"id":4831,"date":"2019-11-25T08:52:06","date_gmt":"2019-11-25T06:52:06","guid":{"rendered":"https:\/\/blog.febi.com\/?p=4831"},"modified":"2019-11-25T10:40:26","modified_gmt":"2019-11-25T08:40:26","slug":"radiator-coolant-more-than-just-antifreeze","status":"publish","type":"post","link":"https:\/\/blog.febi.com\/en\/radiator-coolant-more-than-just-antifreeze\/","title":{"rendered":"Radiator Coolant: More Than Just Antifreeze"},"content":{"rendered":"\n

For many vehicle owners, the perceived demands placed on the coolant in their car’s cooling system are extremely low. In winter, the coolant should not freeze \u2013 in summer, it should not overheat. That’s it. In reality, however, the demands placed on coolants for modern engines are enormous. This is especially on account of the fact that even series engines are becoming lighter, more compact, and more powerful, resulting in an increased heating of individual components.<\/p>\n\n\n\n

Protection Against Frost and Overheating<\/strong><\/h2>\n\n\n\n

Virtually every antifreeze (concentrate) consists of about 90% glycol and 10% additives. Additives are substances that influence the properties of the agent. Automotive coolants are a mixture of water and antifreeze. The ideal mixing ratio is 1:1, which corresponds to an antifreeze protection down to -36\u00b0 C. The maximum possible antifreeze protection of approximately -52\u00b0 C is achieved with a mixture of 2:1 (antifreeze:water). Pure antifreeze reduces the cooling efficiency by around 50% when compared to the 1:1 mixture.<\/p>\n\n\n\n

In addition to lowering the freezing temperature, glycol\nalso contributes to increasing the boiling point which protects the engine from\noverheating in the warmer months. With a mixture of water and antifreeze in a\nratio of 1:1, the boiling point of the coolant is around 107\u00b0 C thus offering\nthe cooling system an enormous performance reserve.<\/p>\n\n\n\n

Tap Water or Distilled Water?<\/strong><\/h2>\n\n\n\n

The argument that distilled water should be added to the\ncooling system stems from the fact that phosphate-containing antifreeze was\nused in the past. These phosphates were incompatible with the minerals found in\ntap water. Since phosphates have not been present in antifreeze for a\nconsiderable time, conventional tap water of drinking quality can be used.<\/p>\n\n\n\n

Distilled water has the fundamental advantage that it hardly\ncontains any minerals that can be deposited into the engine. The disadvantage\nof distilled water, on the other hand, is that the pH level is lower than that\nof tap water. Pure, triple-distilled water achieves a neutral pH value of 7.0.\nTap water has slightly alkaline values usually around 7.5 – 8.0.<\/p>\n\n\n\n

The coolant in the engine should always be slightly alkaline\n(pH value >7) and never acidic (pH value <7), otherwise the seals will be\ndamaged. For this reason, additives are added to each antifreeze to ensure that\nacids are bound and the coolant remains alkaline. Therefore, the small amounts\nof minerals in tap water are negligible when compared to the poorer pH value of\nthe distilled water.<\/p>\n\n\n\n

Protection of the Entire Cooling System<\/strong><\/h2>\n\n\n\n

Antifreeze agents have additional lubricating properties, which allow the coolant to be used as a lubricant for cooling system components (e.g. water pump, thermostat, heating valves). This is particularly important for the slide seal ring of the water pump, which would wear out after a short time without antifreeze.<\/p>\n\n\n\n

The additives in the antifreeze also protect against\ncorrosion and cavitation and also prevent deposits and foam formation. Silicate\nis an additive with excellent corrosion protection properties. If the mixing\nratio of antifreeze and water is incorrectly calculated, the coolant may\ncontain too few protective additives.<\/p>\n\n\n\n

This can lead to corrosion in the entire cooling system. In\nthis case, rust, lime, or dirt can destroy the surfaces of the slide seal ring.\nA sealing of the pump bearing is then no longer guaranteed. When changing the\ncoolant it is therefore advisable to clean and flush the coolant circuit.<\/p>\n\n\n\n

Change Intervals<\/strong><\/h2>\n\n\n\n

The coolant has a certain wear. Some of the additives are\nconsumed over time. Therefore, the coolant loses its antifreeze and corrosion\nprotection as well as its lubricating effect and thermal conductivity. Foam\nformation and deposits can also occur. The durability of a coolant depends on\nits quality and the cleanliness of the entire cooling system.<\/p>\n\n\n\n

Wear is particularly intense if leakage occurs or exhaust\ngases enter the cooling system (e.g. due to a defective cylinder head gasket).\nFor this reason, the coolant should be checked regularly and replaced if\nnecessary. The specifications of the vehicle manufacturer regarding\nspecifications, replacement intervals, miscibility, and mixing ratio must be\nobserved!<\/p>\n