This spring I disassembled an engine from a 1965 MGB that has been in the family for the last 30 years. It has always been filled with a 50/50 mixture of Prestone and tap water. There was virtually no rust anywhere in the cooling system. Now I am hearing that you should only use distilled or de-i…

Distilled water for radiators?

Craig58 April 23, 2008, 12:36am 4

I believe it depends on the quality (hardness) of your tap water. Personally, I only used distilled water in my cars, it is very cheap and available everyplace.