Strangely, Ed's snobby car demands Fresh spring water.

Dear Car Talk

Dear Car Talk | Apr 01, 1991

Dear Tom and Ray:

I live in a town where the water is very hard. Several years ago, I started using a 50/50 mix of antifreeze and distilled water. This mixture seems to work well, and in fact my temperature gauge seems to run approximately five degrees cooler than it used to. The other day in a local barber shop, I mentioned this. The barber said that a customer of his, a transmission man, said distilled water should not be used in the cooling system as it attracts metallic particles. What do you think?

RAY: I think the barber should stick to trimming moustaches, Ed.

TOM: Hard water is water with lots of dissolved minerals in it. Distilled water has no minerals in it. Which would you rather have in your engine? Lots of minerals, or no minerals?

RAY: Minerals deposit themselves on the metal parts of your engine, and can eventually clog vital cooling passages. It's like having too much cholesterol in your arteries.

TOM: In most parts of the country, the water's not hard enough to make this a big problem, but it certainly doesn't do any harm to use distilled water and cut down on the mineral deposits.

RAY: So what you're doing is fine, Edward. And next time this barber gives you authoritative, second-hand automotive advice, the best response would be "Hey, Fred, can you take a little more off the sides?"

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