Distilled water...

[Johnj]

Distilled water is water that has virtually all of its impurities removed through distillation. Distillation involves boiling the water and then condensing the steam into a clean container, leaving most if not all solid contaminants behind.
The contaminants foul the plates inside battery's and leave clogging deposits in cooling systems.

[slimcolo]

Water will not conduct electricity, but if you add a catalyst it will. (this means that battery plates will short out sooner with use of impure water) also when you over charge a battery the boil off is pure water the other parts of acid stay in battery this, plus cost, is why you use distilled water to top off a used battery instead of refilling with acid. This is the best summary I can give of a lecture that my Chem Prof (Dr. John Smith no siht his real name) gave on this subject about 20 yrs ago.

[dean owens]

thanks. learned something new. i knew how distilled water was different... just didn't know how it mattered.