A Laboratory Study on the Effect of Coolant Contaminants in Heavy Duty Applications
Pressure to reduce costs has caused a trend toward extended coolant life in heavy duty applications today. Extended life requires the user to maintain the cooling system within tighter limits over a longer period of time. Ideally, the coolant would be replaced based on need, rather than time or mileage. The introduction of corrosive ions can lead to shortened coolant life and the need to replace the coolant sooner than normal in order to protect the engine. In order to know when to replace the coolant, an understanding of the effects of these corrosive ions in the coolant is necessary. This paper focuses on the effects of chloride and sulfate ions on coolant performance in laboratory tests. Laboratory tests were run on a variety of commercially available heavy duty coolants including organic, inorganic, and treated water systems. The tests consisted of various laboratory procedures used throughout the industry to test the ability of a coolant to protect against corrosion.