Use distilled water in your radiator.

[Keith Bradshaw <bradshaw@utdallas.edu>]

After looking into DI water problems here, and conversations with the North 
Texas Municipal Water
guys and the A&M water guys down south I found they concur on this point.

Use distilled water in your radiator.  Hard water allows calcium buildup in the 
radiator and even 
soft water will do that.  Distilled water should keep the radiator clear 
forever.


mBrad