How does electrolysis affect a radiator?

Answer 1

What is electrolysis and why is it a problem in an automotive cooling system? Lets start by trying to understand electrolysis as it pertains to automobiles. Electrolysis is a destructive force that packs enormous potential to damage not just cooling system components, but any aluminum engine part that has contact with the coolant. The coolant acts as both the catalyst and as the conductor, just like the electrolyte in a battery.The "electrodes" mentioned in the above definition are the aluminum components in the cooling system (like the plates in a battery). The "electrochemical process" mentioned is the aluminum particle (ion) movement, such that leaks (thinning of wall surface) occur. When enough ions have moved, this results in a failure (leak) typically in the radiator or heater due to the thickness (read thinness) of the tube wall surface. A thicker surface (like an aluminum casting) is not more resistant to electrolysis, but is not as likely to leak because it is thicker. However these thicker surfaces may leak anyway if the electrolysis occurs at a gasket surface. Generally you won't know you have an electrolysis problem unless you have (a series of) unexplained leaks. However, to add yet another factor, in some parts of the country (southwest), electrolysis is much more prevalent than others.