Join Date: Jul 2007
Location: Truckee, CA
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I have read that after a long time the anti-freeze coolants lose the rust inhibitor additive
capability? With an iron block engine rust could possibly start forming resulting in the brown color? If the heat exchanger is leaking salt water into the coolant it could perhaps have the same effect. Short of tasting the coolant there may be a way of testing the coolant for salt?