4Crawler

iTrader: (3)

I use deionized water in mine most of the time, less expensive than distilled and works just as well. I also add Water Wetter along with the Toyota Red coolant, ~50:50 mix.

Nismo Convert

You know if you have a dehumidifier in your house that water coming from it is demineralized right? I empty the dehumidifier once a week, and I have enough demineralized water for years, I'll sell you some for a few bucks a gallon is you like .

dlbrunner

Deionized is BAD!!! De Ionized water is very agressive. DeIonized or RO (reverse osmosis) water will corrode stainless steel over time, a lot of RO drinking water plants are going to fiberglass vessels because the stainless ones are not holding up. There are a lot of free radicals in RO water which are very reactive. Also the pH of RO water is lower (more acidic) than distilled or tap water.

With RO plants we see a lot of elevated lead and copper levels after the install. Also Iron, aluminum and nickel will leach into solution. In an engine where the solution is under high temperatures and pressure you will see accelerated corrosion.

Distilled is the best way to go.

tom_mag

I've never heard that before but it sounds like you know what your talking about. I use water from the water softener or from the culligan tap.
In my Buick i use straight water and water wetter. In the Toyota, Toyota anti-freeze 50/50 or 60/40 water/antifreeze. Water cools better than anti-freeze.

Bennito

Lets work backwards.

Commercial antifreezes have various anti-scaling and anti-corrosion chemicals, in addition to ethylene glycol, to keep your cooling system in tip-top shape. Because of those chemicals, there is actually a broad range of water quality standards that your engine cooling system can tolerate. If you follow the directions and mix 50/50 antifreeze with distilled water from the store, you'll be in good shape.

Why a 50/50 mix? For most of contintal america a 50/50 mix will provide adequate freeze protection in winter. 50/50 is easy for the end user to mix. 70% antifreeze / 30% antifreeze will have the largest change in freezing point depression. While water has a higher specific heat than EG, I'm not willing to make comment on if water cools better (especially wtih antifreeze additives that might increase heat transfer coefficient).

Lastly - Deionized vs RO vs distilled. These are all methods of purifying water. none of them is a level of purity. While they separate/purify water based on different principles, at the level of purity we're talking about they can be considered siilar. Why? Because we're trying to get the big chunks out of our tap water for use in an engnine heavily treated with water treatment chemicals (the antifreeze). You may have also noticed that the distilled water you buy in the store is lacking on quality standards as well. indeed its not a well regulated industry. Furthermore, output water quality is a function of input water quality. That is, I've had chance to work with water purification systems in phoenix and colorado springs. Reverse osmosis product water (2 stage) from phoenix tapwater results in colorado tapwater.

Ultimately, this implies that people in various parts of the country may get away with using tap water in their coolant. But why risk it.

sorry for the gaps in knowledge/oversights. only had a few mins to write this.

dlbrunner

Why a 50/50 mix? For most of contintal america a 50/50 mix will provide adequate freeze protection in winter. 50/50 is easy for the end user to mix. 70% antifreeze / 30% antifreeze will have the largest change in freezing point depression. While water has a higher specific heat than EG, I'm not willing to make comment on if water cools better (especially wtih antifreeze additives that might increase heat transfer coefficient).

by mixing water with ethylene glycol you do two things 1 is elevate the boiling point of the mixture. the other is lower the freezing point. I did the calculations in chemistry class in college and 50/50 offers the largest temperature range for the mixture to remain in the liquid phase. Other ingredients in antifreeze may change this byt by and large not by much. other proportions may allow a lower freezing temp, but you will sacrifice on the boiling point and not in a linear fashion.

About the quality in vs out, I question this. A company that is bottleing water for consumption in most cases will be obtaining source water from a large municipality or a fairly large water system. that source water has been treated to meet Safe Drinking Water Standards already. The biggest thing a bottled water company wants is good taste, for that you need to pull out the alkalinity and TDS

While the contaminants of concern would be TDS (total dissolved solids), Alkalinity, and harness. These are what are going to cause deposits. The mentioned nasties are not regulated contaminats and do not need to be removed from water, but treatment R.O and other treatment will remove these..

I don't think the range of water quality is all that great on a higher milage engine, I did a radiator replacement/flush on my exploder and I accidentally put RO water in, within a week a freeze plug corroded and was spewing coolant. when I pulled the new radiator, there was a lot of gunk and mineralized deposits. I think the drastic change in the chemistry broke a lot of the old deposits loose. Coincedence... Maybe. But after looking at several RO plants I have noticed a disturbing trend, they leak and corrode like crazy.

One last note about RO, when used as process water lots of anti corrosion chemicals must be added.

I agree quality in will affect quality out for certain types of treatment like R.O GAC, coag/sedimentation, but it is not as significant of a factor in distillation. The nastier the water going in to distillation will just leave more deposits in the distillation vessel.