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Antifreeze/Coolants Brands

KOST USA manufactures a comprehensive range of high performance ethylene glycol and propylene glycol-based antifreeze/coolants for automotive, heavy-duty, on-road, off-road and marine applications. Our extensive portfolio of brands are made with virgin raw materials and manufactured to rigid quality assurance levels. Each brand formulation is formulated to meet the latest ASTM standards as well as OEM (Original Equipment Manufacturer) approved chemistries. Additionally, all KOST USA antifreeze/coolants contain Bitter-Aid™ an anti-consumption additive.

Antifreeze/Coolant FAQ’s

Antifreeze/Coolant is comprised of a heat transfer liquid, typically high quality deionized/reverse osmosis (DI/RO) water, virgin glycol, corrosion inhibitors and additives depending on the coolant type which may be organic or inorganic in nature.

Water is an adequate heat transfer fluid but is limited in temperature range. Glycol when added to water offers an operating temperature range that is higher than either fluid used by itself. Ethylene glycol (EG) is the most prevalent glycol used in antifreeze/coolant, but environmentally friendly fluids such as Propylene Glycol (PG) may be used as well.

Yes. Ideally water should be used that is free of dissolved minerals which directly contribute to scale formation. Scale reduces the fluid’s ability to transfer heat and can lead to engine cooling system failures. Original equipment manufacturers (OEM) specifications and standards have quality requirements for the water appropriate for use in antifreeze/coolants by both the coolant manufacturer and the consumer. Municipal or well water can contain amounts of dissolved minerals and fine particulate and is not recommended to dilute coolant concentrate for this reason. Deionized water has been specifically processed to remove dissolved minerals and particulate making it ideally suited for use in coolants.

No. Glycol-based coolant concentrate in of itself does not offer sufficient heat transfer and corrosion protection. To reach the desired heat transfer and attributes, a coolant concentrate must always be diluted with high quality water, preferable deionized water at a 50:50 ratio with coolant concentrate. Glycol-based coolant concentrate should always be diluted to between 30% and 70% strength as mixtures outside of these limits would compromise coolant performance.

Volume dilutions and temperature operating ranges are provided below for typical ethylene glycol coolant concentrate:

Generally speaking, Ethylene Glycol (EG) fluids, conventional (inorganic) in nature, have a shelf life of 18 months. Organic Acid Technology (OAT) fluids have a shelf life of approximately 8 years. For environmentally-friendly fluids blended with Propylene Glycol (PG), the shelf life for conventional fluids is estimated at 12 months and (OAT) fluids at 5 years. These statements are to be interpreted as a general guide based on normal storage conditions. Fluid shelf life may be shorter or longer depending on those conditions.

Ideally, Antifreeze/Coolant should be stored in utilizing stainless or carbon steel, poly, and plastic. Excessive heat of over 100°F and long-term exposure to UV sunlight should be avoided.

A refractometer is the best and most economical field device to measure the glycol concentration (freeze and boil protection). The use of hydrometers can be less effective and are not recommended. Supplemental Coolant Additive (SCA) test strips can be used to determine inhibitor levels as part of a proper coolant maintenance program. Most test strips on the market are specific to heavy duty diesel coolants and measure either nitrite or molybdate levels.

Using a conventional coolant will not disrupt the ability of the extended life coolant to protect the cooling system but will reduce the extended life properties. Therefore, it is not recommended to top-up an extended life coolant OAT with any coolant other than an extended life as this will negate the extended service life desired by the original coolant in the cooling system.

Cavitation occurs from vibrations in fluid during operation without the adequate inhibitors to protect against the implosions against cooling system materials. Low pressure results in the vaporization of the fluid and gas bubble formation and then collapses when the pressure normalizes. In an engine, this typically occurs within the water pump and along the cylinder liners as a result of the piston movement and is most common in diesel engines. This constant bubble creation and collapse along surfaces can be repetitive and violent enough to corrode the underlining metal resulting in cooling system failure. Corrosion inhibitors such as nitrite and/or molybdate are preferably used in coolant to prevent this cavitation corrosion since they form barrier films on metal surfaces.