Many engine failures are the result of improper antifreeze usage. To protect equipment from coolant–related damage, it is critical to know the different antifreeze types, required mix ratios and problems that could result from improper use. A 100 percent antifreeze solution will turn to a solid at 9°F (–13°C). For best all–around protection, use a 50:50 mixture of antifreeze and water. Concentrated antifreeze needs water for chemical balance and optimum performance.
Antifreeze to Water MixCoolant should not be mixed with hard tap water. Hard tap water has excessive calcium and magnesium deposits that can cause scaling, which will result in inadequate heat transfer. To avoid scaling, use only soft or de–ionized water that is not treated with salts or chlorides, when mixing water and antifreeze. (OEMs publish limits in parts per million (ppm) for hardness, chlorides, sulfates and total dissolved solids for the water used to dilute antifreeze.)
Supplement Coolant Additives (SCAs)Fresh antifreeze also requires a supplemental coolant additive (SCA) when used in heavy–duty engines. The supplemental coolant additive is depleted during use and needs to be added periodically to the coolant system. However, there is antifreeze available that contains the SCA (pre–charged antifreeze) and the proper water to antifreeze ratio (pre–charged/pre–mixed).
Castrol has several coolant products that are premixed with the proper additives and water ratios that ensure optimum engine performance. For best results, check for proper additive treat rates, pH levels, and freeze point twice a year to determine the condition of the antifreeze.