BMW coolant -- distilled or tap water?
- Thread starter dparm
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60:40 distilled to coolant plus a bottle of Water Wetter is what I use in all of my Bimmers, except my track car which is just distilled and two bottles of WW (Zionsville rad plus other cooling system mods = nearly 1.8x the capacity of stock).
BMW recommends distilled water, BUT - I beleive it has to do with the much higher mineral concentrations of European tap water than here in the US. I've always used tap water. Municipal tap water will have such low concentrations of minerals that it's a non-issue.
Originally Posted By: dparm
Finally changing out the coolant in my M3 since it just ticked 50k. BMW claims it's lifetime but I call [censored] on that.
The OEM concentrate bottles don't say you need to use distilled water, but they also don't say to avoid tap water. It is a phosphate-free fluid so in theory there is no benefit to using tap water.
Does anyone know what BMW recommends in this regard? The dealer was of no help: "well it's lifetime so you shouldn't have to change it out".
Seriously???? Don't clean your shower for a month..do you want the stuff that collects on the walls in your Bimmer's cooling system? I'm on municipal water with the best whole house water softener Kinetico sells and that water won't come near my cooling system or even my windshield washer reservoir, for that matter. Buy the distilled.
Finally changing out the coolant in my M3 since it just ticked 50k. BMW claims it's lifetime but I call [censored] on that.
The OEM concentrate bottles don't say you need to use distilled water, but they also don't say to avoid tap water. It is a phosphate-free fluid so in theory there is no benefit to using tap water.
Does anyone know what BMW recommends in this regard? The dealer was of no help: "well it's lifetime so you shouldn't have to change it out".
Seriously???? Don't clean your shower for a month..do you want the stuff that collects on the walls in your Bimmer's cooling system? I'm on municipal water with the best whole house water softener Kinetico sells and that water won't come near my cooling system or even my windshield washer reservoir, for that matter. Buy the distilled.
Where does BMW recommend distilled water? For what, the battery?
I mean, if all they have is pre-mix why would they recommend water at all for the cooling system?
Originally Posted By: KenO
BMW recommends distilled water, BUT - I believe it has to do with the much higher mineral concentrations of European tap water than here in the US. I've always used tap water. Municipal tap water will have such low concentrations of minerals that it's a non-issue.
I mean, if all they have is pre-mix why would they recommend water at all for the cooling system?
Originally Posted By: KenO
BMW recommends distilled water, BUT - I believe it has to do with the much higher mineral concentrations of European tap water than here in the US. I've always used tap water. Municipal tap water will have such low concentrations of minerals that it's a non-issue.
It depends on the source. I've lived in a few places over the years. Where I grew up (and still live) has some of the softest water in the country. It's Sierra snowmelt from a river in the Sierra Nevada foothills. Other than that, the storage reservoirs might also contain local rainwater. I used to keep aquarium fish and used a calcium/magnesium water hardness testing kit. The water typically registered 30-40 mg/liter, which is considered extremely soft.
I bought a house in a city served mostly by city-owned wells. It has this odd smell. It leaves crusty rings in the toilet. You thought hard about washing your car with this water. I tried using the same water hardness testing kit, which involved adding drops from one bottle until the color changed. I gave up after about 40 drops.
I've personally used distilled water, but I don't sweat it when I have some service done and they use high quality local tap water. I had my radiator replaced a year ago, and the guy who installed it did it with the OEM coolant I provided. His water would be from the same source supplying the area where I grew up.
Also - most premix coolant wouldn't use distilled water, which is expensive and takes time. It's almost always deionized water, which is faster and cheaper to produce on site. I remember my HS chemistry lab had a water deionizer (probably an ion exchange system) that we used for lab assignments. It wouldn't have the absolute purity of distilled water, but for coolant mix, the most important thing is to remove the dissolved minerals.
I bought a house in a city served mostly by city-owned wells. It has this odd smell. It leaves crusty rings in the toilet. You thought hard about washing your car with this water. I tried using the same water hardness testing kit, which involved adding drops from one bottle until the color changed. I gave up after about 40 drops.
I've personally used distilled water, but I don't sweat it when I have some service done and they use high quality local tap water. I had my radiator replaced a year ago, and the guy who installed it did it with the OEM coolant I provided. His water would be from the same source supplying the area where I grew up.
Also - most premix coolant wouldn't use distilled water, which is expensive and takes time. It's almost always deionized water, which is faster and cheaper to produce on site. I remember my HS chemistry lab had a water deionizer (probably an ion exchange system) that we used for lab assignments. It wouldn't have the absolute purity of distilled water, but for coolant mix, the most important thing is to remove the dissolved minerals.
Originally Posted By: GatorJ
Originally Posted By: dparm
Finally changing out the coolant in my M3 since it just ticked 50k. BMW claims it's lifetime but I call [censored] on that.
The OEM concentrate bottles don't say you need to use distilled water, but they also don't say to avoid tap water. It is a phosphate-free fluid so in theory there is no benefit to using tap water.
Does anyone know what BMW recommends in this regard? The dealer was of no help: "well it's lifetime so you shouldn't have to change it out".
Seriously???? Don't clean your shower for a month..do you want the stuff that collects on the walls in your Bimmer's cooling system? I'm on municipal water with the best whole house water softener Kinetico sells and that water won't come near my cooling system or even my windshield washer reservoir, for that matter. Buy the distilled.
A small amount of minerals from soft tap water won't hurt anything. There are additives to keep it from settling out. Now well water would be another story.
Originally Posted By: dparm
Finally changing out the coolant in my M3 since it just ticked 50k. BMW claims it's lifetime but I call [censored] on that.
The OEM concentrate bottles don't say you need to use distilled water, but they also don't say to avoid tap water. It is a phosphate-free fluid so in theory there is no benefit to using tap water.
Does anyone know what BMW recommends in this regard? The dealer was of no help: "well it's lifetime so you shouldn't have to change it out".
Seriously???? Don't clean your shower for a month..do you want the stuff that collects on the walls in your Bimmer's cooling system? I'm on municipal water with the best whole house water softener Kinetico sells and that water won't come near my cooling system or even my windshield washer reservoir, for that matter. Buy the distilled.
A small amount of minerals from soft tap water won't hurt anything. There are additives to keep it from settling out. Now well water would be another story.
I once read a thing from Royal Purple advising people to not use distilled water if they were using a straight water and Purple Ice mixture with no antifreeze.
Purple Ice
Not so much applicable in OP's case, but it is not exactly unheard of for water other than distilled to be recommended for the cooling system.
Purple Ice
Not so much applicable in OP's case, but it is not exactly unheard of for water other than distilled to be recommended for the cooling system.
It is silly, though, for them to advise specifically against distilled water. Much of this is based on the completely misunderstood notion of distilled water being corrosive. All water is corrosive. There's a reason they call water the universal solvent, after all.
Originally Posted By: WANG
I once read a thing from Royal Purple advising people to not use distilled water if they were using a straight water and Purple Ice mixture with no antifreeze.
Purple Ice
Not so much applicable in OP's case, but it is not exactly unheard of for water other than distilled to be recommended for the cooling system.
Prestone used to sell a deoinized water that they claimed was better than distilled for cooling systems. Someone apparently found one (label looks pretty beat up) and is looking to sell on eBay as a collector's item:
The biggest issue I've heard is that some people dump the distilled water directly into the cooling system. Distilled water is nearly almost "carbonic acid" because of dissolved CO2. It's an extremely weak acid, but there are reports that after pouring just that in a radiator, the aluminum starts precipitating out this black corrosion. It really needs to be mixed with the coolant, which contains acid neutralizers. Even a small quantity of coolant should do the trick.
I mentioned my testing kits. I used to test distilled water and tap water with water hardness and pH kits. Distilled water always tested as acidic but was always neutralized and made alkaline with a little bit of tap water. I also remember trying stuff like testing soft tap water that had gone through a Brita filter. The hardness went down to zero (I didn't even have to put in a reactive drop) and the pH indicated it was acidic.
I once read a thing from Royal Purple advising people to not use distilled water if they were using a straight water and Purple Ice mixture with no antifreeze.
Purple Ice
Not so much applicable in OP's case, but it is not exactly unheard of for water other than distilled to be recommended for the cooling system.
Prestone used to sell a deoinized water that they claimed was better than distilled for cooling systems. Someone apparently found one (label looks pretty beat up) and is looking to sell on eBay as a collector's item:
The biggest issue I've heard is that some people dump the distilled water directly into the cooling system. Distilled water is nearly almost "carbonic acid" because of dissolved CO2. It's an extremely weak acid, but there are reports that after pouring just that in a radiator, the aluminum starts precipitating out this black corrosion. It really needs to be mixed with the coolant, which contains acid neutralizers. Even a small quantity of coolant should do the trick.
I mentioned my testing kits. I used to test distilled water and tap water with water hardness and pH kits. Distilled water always tested as acidic but was always neutralized and made alkaline with a little bit of tap water. I also remember trying stuff like testing soft tap water that had gone through a Brita filter. The hardness went down to zero (I didn't even have to put in a reactive drop) and the pH indicated it was acidic.
Test kits may show distilled water as acidic but that has no bearing on whether the water is actually acidic or not. The equilibrium reaction generating that indication is very limited and is more of a false indication than anything else. Any aqueous solution near neutral will exhibit this behavior unless it is buffered. There is very little dissolved CO2 in distilled water unless it is exposed to the atmosphere, and even then it is very small. It will not be enough to corrode anything by that mechanism.
Originally Posted By: y_p_w
Distilled water is nearly almost "carbonic acid" because of dissolved CO2. It's an extremely weak acid, but there are reports that after pouring just that in a radiator, the aluminum starts precipitating out this black corrosion. It really needs to be mixed with the coolant, which contains acid neutralizers. Even a small quantity of coolant should do the trick.
I mentioned my testing kits. I used to test distilled water and tap water with water hardness and pH kits. Distilled water always tested as acidic but was always neutralized and made alkaline with a little bit of tap water. I also remember trying stuff like testing soft tap water that had gone through a Brita filter. The hardness went down to zero (I didn't even have to put in a reactive drop) and the pH indicated it was acidic.
Originally Posted By: y_p_w
Distilled water is nearly almost "carbonic acid" because of dissolved CO2. It's an extremely weak acid, but there are reports that after pouring just that in a radiator, the aluminum starts precipitating out this black corrosion. It really needs to be mixed with the coolant, which contains acid neutralizers. Even a small quantity of coolant should do the trick.
I mentioned my testing kits. I used to test distilled water and tap water with water hardness and pH kits. Distilled water always tested as acidic but was always neutralized and made alkaline with a little bit of tap water. I also remember trying stuff like testing soft tap water that had gone through a Brita filter. The hardness went down to zero (I didn't even have to put in a reactive drop) and the pH indicated it was acidic.
Originally Posted By: kschachn
Test kits may show distilled water as acidic but that has no bearing on whether the water is actually acidic or not. The equilibrium reaction generating that indication is very limited and is more of a false indication than anything else. Any aqueous solution near neutral will exhibit this behavior unless it is buffered. There is very little dissolved CO2 in distilled water unless it is exposed to the atmosphere, and even then it is very small. It will not be enough to corrode anything by that mechanism.
I know the effect is small (perhaps insignificant in the long run) but there are people who report clearly visible aluminum corrosion from using distilled water itself as a rinse or those who attempt to use straight water for racing purposes. My point is that it is incredibly easy to buffer distilled water by mixing it with something that serves that purpose, including uncut coolant solutions or even a small amount of low mineral tap or spring water.
I've heard of people so paranoid that they use distilled water to rinse out a radiator (GM instructions used to be to run a hose through the rad cap). Even if I use distilled water to cut the coolant, I doubt I'd go so far as to pour distilled water as a rinse. Maybe buffer it with something.
Test kits may show distilled water as acidic but that has no bearing on whether the water is actually acidic or not. The equilibrium reaction generating that indication is very limited and is more of a false indication than anything else. Any aqueous solution near neutral will exhibit this behavior unless it is buffered. There is very little dissolved CO2 in distilled water unless it is exposed to the atmosphere, and even then it is very small. It will not be enough to corrode anything by that mechanism.
I know the effect is small (perhaps insignificant in the long run) but there are people who report clearly visible aluminum corrosion from using distilled water itself as a rinse or those who attempt to use straight water for racing purposes. My point is that it is incredibly easy to buffer distilled water by mixing it with something that serves that purpose, including uncut coolant solutions or even a small amount of low mineral tap or spring water.
I've heard of people so paranoid that they use distilled water to rinse out a radiator (GM instructions used to be to run a hose through the rad cap). Even if I use distilled water to cut the coolant, I doubt I'd go so far as to pour distilled water as a rinse. Maybe buffer it with something.
Well any corrosion isn't caused by the water per se. The solubility of metals in water isn't that high in an absolute sense, especially in a closed system. Once the water is saturated it won't dissolve any more. I don't know what the solubility of iron or aluminum is in water, but it isn't very high when compared to the mass of the engine.
Corrosion in a cooling system is due to other factors that I'm not very familiar with. Things like dissimilar (Galvanic) corrosion. Something is acting as an anode and something else as a cathode. The coolant is going to inhibit this corrosion by buffering, that is what you miss out by using straight water (that and the boiling point/freezing point elevation/suppression). There are other methods of corrosion that I'm not very familiar with that I'm sure occur in cooling systems, especially at elevated temperatures.
The point is that it's not the water. The water isn't going to corrode the metals by leaching.
Corrosion in a cooling system is due to other factors that I'm not very familiar with. Things like dissimilar (Galvanic) corrosion. Something is acting as an anode and something else as a cathode. The coolant is going to inhibit this corrosion by buffering, that is what you miss out by using straight water (that and the boiling point/freezing point elevation/suppression). There are other methods of corrosion that I'm not very familiar with that I'm sure occur in cooling systems, especially at elevated temperatures.
The point is that it's not the water. The water isn't going to corrode the metals by leaching.
Originally Posted By: kschachn
Well any corrosion isn't caused by the water per se. The solubility of metals in water isn't that high in an absolute sense, especially in a closed system. Once the water is saturated it won't dissolve any more. I don't know what the solubility of iron or aluminum is in water, but it isn't very high when compared to the mass of the engine.
Corrosion in a cooling system is due to other factors that I'm not very familiar with. Things like dissimilar (Galvanic) corrosion. Something is acting as an anode and something else as a cathode. The coolant is going to inhibit this corrosion by buffering, that is what you miss out by using straight water (that and the boiling point/freezing point elevation/suppression). There are other methods of corrosion that I'm not very familiar with that I'm sure occur in cooling systems, especially at elevated temperatures.
The point is that it's not the water. The water isn't going to corrode the metals by leaching.
I was never referring to corrosion as a matter of using distilled water in a properly mixed coolant/water mixture. However, there are reports that when poured into an aluminum radiator that the slight acidity is enough to cause a bit of quick precipitation of stuff. The whole point of a radiator flush is to rinse out as much of the original coolant as possible. So by the point it's flushed away there's only going to be bare distilled water. In any case, I never said it was anything severe enough to worry about, but it would still be advisable to mix with coolant first.
Aluminum cans have to be coated to resist the acidity of most carbonated beverages as well as phosphoric acid.
Well any corrosion isn't caused by the water per se. The solubility of metals in water isn't that high in an absolute sense, especially in a closed system. Once the water is saturated it won't dissolve any more. I don't know what the solubility of iron or aluminum is in water, but it isn't very high when compared to the mass of the engine.
Corrosion in a cooling system is due to other factors that I'm not very familiar with. Things like dissimilar (Galvanic) corrosion. Something is acting as an anode and something else as a cathode. The coolant is going to inhibit this corrosion by buffering, that is what you miss out by using straight water (that and the boiling point/freezing point elevation/suppression). There are other methods of corrosion that I'm not very familiar with that I'm sure occur in cooling systems, especially at elevated temperatures.
The point is that it's not the water. The water isn't going to corrode the metals by leaching.
I was never referring to corrosion as a matter of using distilled water in a properly mixed coolant/water mixture. However, there are reports that when poured into an aluminum radiator that the slight acidity is enough to cause a bit of quick precipitation of stuff. The whole point of a radiator flush is to rinse out as much of the original coolant as possible. So by the point it's flushed away there's only going to be bare distilled water. In any case, I never said it was anything severe enough to worry about, but it would still be advisable to mix with coolant first.
Aluminum cans have to be coated to resist the acidity of most carbonated beverages as well as phosphoric acid.
OK,well we are beating this horse to death
My point is that there is no "acidity" to distilled water. Yes, it can dissolve carbon dioxide from the atmosphere if exposed, but this is a very small amount of free H+ unless the partial pressure of the dissolved CO2 is very high. It gets back to the statement you made about your pH measurement showing it as acidic. Measuring the pH of a near-neutral solution (especially distilled water) is nearly impossible and also nearly meaningless. Like a quantum measurement, the very act of attempting to measure the value disturbs the system more than the thing you are trying to measure. The amount of dissociation in distilled water is vanishingly small.
Now carbonated beverages is another thing. Here like you mention, the main aggressor is the phosphoric acid. The carbon dioxide in the solution is under pressure too and contributes, but a whole lot less than that phosphoric acid.
Off topic, I always chuckle at those Facebook posts where people show Coca-Cola cleaning a toilet or something due to it's acidity. They always make the statement about how introducing this horribly acidic substance into your body is somehow near lethal. No doubt it is bad for your teeth (some people more than others), especially if it is allowed to linger in the mouth. But your esophagus is not particularly vulnerable, and once it enters the much more acidic environment of the stomach it quickly becomes a non-issue. Drinking soda through a straw helps a lot to get it past the teeth BTW.
Originally Posted By: y_p_w
Originally Posted By: kschachn
Well any corrosion isn't caused by the water per se. The solubility of metals in water isn't that high in an absolute sense, especially in a closed system. Once the water is saturated it won't dissolve any more. I don't know what the solubility of iron or aluminum is in water, but it isn't very high when compared to the mass of the engine.
Corrosion in a cooling system is due to other factors that I'm not very familiar with. Things like dissimilar (Galvanic) corrosion. Something is acting as an anode and something else as a cathode. The coolant is going to inhibit this corrosion by buffering, that is what you miss out by using straight water (that and the boiling point/freezing point elevation/suppression). There are other methods of corrosion that I'm not very familiar with that I'm sure occur in cooling systems, especially at elevated temperatures.
The point is that it's not the water. The water isn't going to corrode the metals by leaching.
I was never referring to corrosion as a matter of using distilled water in a properly mixed coolant/water mixture. However, there are reports that when poured into an aluminum radiator that the slight acidity is enough to cause a bit of quick precipitation of stuff. The whole point of a radiator flush is to rinse out as much of the original coolant as possible. So by the point it's flushed away there's only going to be bare distilled water. In any case, I never said it was anything severe enough to worry about, but it would still be advisable to mix with coolant first.
Aluminum cans have to be coated to resist the acidity of most carbonated beverages as well as phosphoric acid.
My point is that there is no "acidity" to distilled water. Yes, it can dissolve carbon dioxide from the atmosphere if exposed, but this is a very small amount of free H+ unless the partial pressure of the dissolved CO2 is very high. It gets back to the statement you made about your pH measurement showing it as acidic. Measuring the pH of a near-neutral solution (especially distilled water) is nearly impossible and also nearly meaningless. Like a quantum measurement, the very act of attempting to measure the value disturbs the system more than the thing you are trying to measure. The amount of dissociation in distilled water is vanishingly small.
Now carbonated beverages is another thing. Here like you mention, the main aggressor is the phosphoric acid. The carbon dioxide in the solution is under pressure too and contributes, but a whole lot less than that phosphoric acid.
Off topic, I always chuckle at those Facebook posts where people show Coca-Cola cleaning a toilet or something due to it's acidity. They always make the statement about how introducing this horribly acidic substance into your body is somehow near lethal. No doubt it is bad for your teeth (some people more than others), especially if it is allowed to linger in the mouth. But your esophagus is not particularly vulnerable, and once it enters the much more acidic environment of the stomach it quickly becomes a non-issue. Drinking soda through a straw helps a lot to get it past the teeth BTW.
Originally Posted By: y_p_w
Originally Posted By: kschachn
Well any corrosion isn't caused by the water per se. The solubility of metals in water isn't that high in an absolute sense, especially in a closed system. Once the water is saturated it won't dissolve any more. I don't know what the solubility of iron or aluminum is in water, but it isn't very high when compared to the mass of the engine.
Corrosion in a cooling system is due to other factors that I'm not very familiar with. Things like dissimilar (Galvanic) corrosion. Something is acting as an anode and something else as a cathode. The coolant is going to inhibit this corrosion by buffering, that is what you miss out by using straight water (that and the boiling point/freezing point elevation/suppression). There are other methods of corrosion that I'm not very familiar with that I'm sure occur in cooling systems, especially at elevated temperatures.
The point is that it's not the water. The water isn't going to corrode the metals by leaching.
I was never referring to corrosion as a matter of using distilled water in a properly mixed coolant/water mixture. However, there are reports that when poured into an aluminum radiator that the slight acidity is enough to cause a bit of quick precipitation of stuff. The whole point of a radiator flush is to rinse out as much of the original coolant as possible. So by the point it's flushed away there's only going to be bare distilled water. In any case, I never said it was anything severe enough to worry about, but it would still be advisable to mix with coolant first.
Aluminum cans have to be coated to resist the acidity of most carbonated beverages as well as phosphoric acid.
Looks like we have a good debate going on here! I remember an article in Sport Rider magazine that I read not too long ago about radiator leak issues.
In essence the main debate between the two is that tap water has mineral content, and with that the minerals have ions and an electrical charge. This of course can lead to corrosion or a buildup of minerals within the coolant lines/passages. So the use of distilled water that has lost its mineral content would henceforth solve the problem, but the issue with distilled water is that since it is stripped of all minerals, the water has a chemical need to replace the lost minerals, thus acting on the aluminium or other metals it comes in contact. In a nut shell, here is a quote from the article that was forwarded to Royal Purple for a technical response:
"The company responded that under normal use, chemically, distilled/demineralized/deionoized can be corrosive to aluminum components. This is due to the fact that the water is stripped of all minerals (being left with just about only hydrogen and oxygen, H20 ) and the water has a chemical need to replace the minerals, it is hungry so to speak and it will happily take the aluminum. This is a chemical attack. Further, they state that the cooling tubes and fins are aluminum and don't need much corrosion to leak.
The response goes on to say that distilled water is a holdover from when cooling systems consisted of brass/copper radiators and steel in the engine and water pump. The Royal Purple company recommends filtered drinking water or tap water, preferably the inexpensive grocery store bottled water.
This is the first time I've heard of this reasoning, but it sounds reasonable from a chemical standpoint. Any thoughts on the subject from our resident Chemists?
In essence the main debate between the two is that tap water has mineral content, and with that the minerals have ions and an electrical charge. This of course can lead to corrosion or a buildup of minerals within the coolant lines/passages. So the use of distilled water that has lost its mineral content would henceforth solve the problem, but the issue with distilled water is that since it is stripped of all minerals, the water has a chemical need to replace the lost minerals, thus acting on the aluminium or other metals it comes in contact. In a nut shell, here is a quote from the article that was forwarded to Royal Purple for a technical response:
"The company responded that under normal use, chemically, distilled/demineralized/deionoized can be corrosive to aluminum components. This is due to the fact that the water is stripped of all minerals (being left with just about only hydrogen and oxygen, H20 ) and the water has a chemical need to replace the minerals, it is hungry so to speak and it will happily take the aluminum. This is a chemical attack. Further, they state that the cooling tubes and fins are aluminum and don't need much corrosion to leak.
The response goes on to say that distilled water is a holdover from when cooling systems consisted of brass/copper radiators and steel in the engine and water pump. The Royal Purple company recommends filtered drinking water or tap water, preferably the inexpensive grocery store bottled water.
This is the first time I've heard of this reasoning, but it sounds reasonable from a chemical standpoint. Any thoughts on the subject from our resident Chemists?
Originally Posted By: Analyzer
Looks like we have a good debate going on here! I remember an article in Sport Rider magazine that I read not too long ago about radiator leak issues.
In essence the main debate between the two is that tap water has mineral content, and with that the minerals have ions and an electrical charge. This of course can lead to corrosion or a buildup of minerals within the coolant lines/passages. So the use of distilled water that has lost its mineral content would henceforth solve the problem, but the issue with distilled water is that since it is stripped of all minerals, the water has a chemical need to replace the lost minerals, thus acting on the aluminium or other metals it comes in contact. In a nut shell, here is a quote from the article that was forwarded to Royal Purple for a technical response:
"The company responded that under normal use, chemically, distilled/demineralized/deionoized can be corrosive to aluminum components. This is due to the fact that the water is stripped of all minerals (being left with just about only hydrogen and oxygen, H20 ) and the water has a chemical need to replace the minerals, it is hungry so to speak and it will happily take the aluminum. This is a chemical attack. Further, they state that the cooling tubes and fins are aluminum and don't need much corrosion to leak.
The response goes on to say that distilled water is a holdover from when cooling systems consisted of brass/copper radiators and steel in the engine and water pump. The Royal Purple company recommends filtered drinking water or tap water, preferably the inexpensive grocery store bottled water.
This is the first time I've heard of this reasoning, but it sounds reasonable from a chemical standpoint. Any thoughts on the subject from our resident Chemists?
What Royal Purple says is that distilled or DI water should not be used in straight water cooling systems, such as cooling systems prepared for racing.
Quote:
http://royalpurpleconsumer.com/wp-content/uploads/PS_Purple_Ice.pdf
TECH TIP
Distilled water should not be used in straight water cooling systems with aluminum radiators.
Filtered drinking water or tap water is recommended for such cooling systems.
The key is that you're actually mixing the distilled or DI water with some sort of coolant concentrate that contains corrosion inhibitors and other things that will keep that property in check. They key is to mix it before pouring it in.
Every premix coolant on the market uses DI or demineralized water. I just bought a gallon of Honda Type 2 for my wife's Civic, and the front label says it's blended with deionized water.
Quote:
http://www.prestone.com/products/antifreeze_coolant/product_list?select_region=1#Overview-410
Prestone® 50/50 Ready-to-Use Prediluted Extended Life Antifreeze/Coolant is a blend of 50% antifreeze/coolant for temperature and corrosion protection and 50% demineralized water for heat transfer protection.
Looks like we have a good debate going on here! I remember an article in Sport Rider magazine that I read not too long ago about radiator leak issues.
In essence the main debate between the two is that tap water has mineral content, and with that the minerals have ions and an electrical charge. This of course can lead to corrosion or a buildup of minerals within the coolant lines/passages. So the use of distilled water that has lost its mineral content would henceforth solve the problem, but the issue with distilled water is that since it is stripped of all minerals, the water has a chemical need to replace the lost minerals, thus acting on the aluminium or other metals it comes in contact. In a nut shell, here is a quote from the article that was forwarded to Royal Purple for a technical response:
"The company responded that under normal use, chemically, distilled/demineralized/deionoized can be corrosive to aluminum components. This is due to the fact that the water is stripped of all minerals (being left with just about only hydrogen and oxygen, H20 ) and the water has a chemical need to replace the minerals, it is hungry so to speak and it will happily take the aluminum. This is a chemical attack. Further, they state that the cooling tubes and fins are aluminum and don't need much corrosion to leak.
The response goes on to say that distilled water is a holdover from when cooling systems consisted of brass/copper radiators and steel in the engine and water pump. The Royal Purple company recommends filtered drinking water or tap water, preferably the inexpensive grocery store bottled water.
This is the first time I've heard of this reasoning, but it sounds reasonable from a chemical standpoint. Any thoughts on the subject from our resident Chemists?
What Royal Purple says is that distilled or DI water should not be used in straight water cooling systems, such as cooling systems prepared for racing.
Quote:
http://royalpurpleconsumer.com/wp-content/uploads/PS_Purple_Ice.pdf
TECH TIP
Distilled water should not be used in straight water cooling systems with aluminum radiators.
Filtered drinking water or tap water is recommended for such cooling systems.
The key is that you're actually mixing the distilled or DI water with some sort of coolant concentrate that contains corrosion inhibitors and other things that will keep that property in check. They key is to mix it before pouring it in.
Every premix coolant on the market uses DI or demineralized water. I just bought a gallon of Honda Type 2 for my wife's Civic, and the front label says it's blended with deionized water.
Quote:
http://www.prestone.com/products/antifreeze_coolant/product_list?select_region=1#Overview-410
Prestone® 50/50 Ready-to-Use Prediluted Extended Life Antifreeze/Coolant is a blend of 50% antifreeze/coolant for temperature and corrosion protection and 50% demineralized water for heat transfer protection.
I hear ya y_p_w, I personally used filtered drinking water when I started working on my first car, but have since then switched to Distilled water for coolant replacements. I completely agree with the recommendation that Royal Purple made for water only coolant systems that you posted, but the article I'm referring to is a direct response between Royal Purple and Sport Rider magazine, with their recommendations being made regarding a Suzuki GSXR750 with an inline 4 aluminium block and radiator that specifically uses a standard 50/50 mix of coolant/water, not a water only system.
I'll see if I can find the article online, as I have the actual magazine article at home.
I'll see if I can find the article online, as I have the actual magazine article at home.
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