Distilled water bad? Use reverse osmosis water instead?

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Originally Posted by Lou_Boyle
+1 on Shannow's comments. The only thing to add to that is that because RO/distilled/deionized water does not have a bunch of other chemical ions in it, some of which are inherently corrosive, the anti corrosion, anti scaling and pH adjusting additives in the antifreeze can do their job unimpeded with no competition.


Right, you're absolutely correct. Coolant mfgs start out with absolutely zero mineral water and formulate their additive pkg based on that.

Simply put, if you want your coolant to perform at it's best according to how the coolant mfg designed it, use distilled or demineralized water.
 
I worked maintenance at a local hospital , close to 40 years ago .

The boiler make up water was RO water . I was told they had to add " very little " chemicals to the make up water .

They also had a de-ionizing setup , which was intended to remove every thing from the RO water ( much smaller quantities ) . The DI water was piped to the kitchen and to the lab or pharmacy ( can not remember which ) . PVC pipe was used to carry DI water from the plant to those locations . I was told if metal pipe was used , the water would no longer be DI water when it arrived .

Our foreman was a plumber . He had to spend a LOT of tome messing with the DI equipment .
 
Originally Posted by das_peikko
Distilled water pulls minerals out of the engine block? Boy that does it right there. I've heard everything now.
lol.gif



MB, years back, did say Not to use distilled water in their engine coolant because of metallic leaching. May have changed by now because of different cooling system metallurgy since then. I do know deionized water is very aggressive and is sometime used for cleaning. Maybe this is where the "hungry" water theory originated.
 
Originally Posted by willbur
MB, years back, did say Not to use distilled water in their engine coolant because of metallic leaching. May have changed by now because of different cooling system metallurgy since then. I do know deionized water is very aggressive and is sometime used for cleaning. Maybe this is where the "hungry" water theory originated.

Yes it is, but as I stated earlier that only makes a hill of difference in an open system, not in a closed one. Water can only hold so much of any one element in suspension until it becomes saturated, and in a cooling system that is on the order of micrograms. But this would only apply to a system filled with water only, once you mix it with coolant it no longer applies.

An open system where fresh distilled, RO or de-ionized water is continuously flowing over metallic surfaces is where it would be a problem. But it is complete myth that it is a problem in a closed cooling system especially when mixed with coolant.
 
Originally Posted by atikovi
Guy says distilled water is bad because it pulls minerals, aluminum and iron oxides from the block. Says to use reverse osmosis water or filtered rain water. Go to time 5:55: https://www.youtube.com/watch?v=2ovO1esqzVo Thoughts?

I flush with a chemical flush and tap water. I flush the tap water with about 8-10 gallons of WM distilled water. Whatever distilled water that remains in the block/radiator mixes with the full strength coolant I add.
 
Scale is a problem in boilers because you are boiling off water and leaving behind the minerals. Plus you are using make up water on a regular basis, depending how many steam leaks there are, which contains a supply of new minerals if not treating the water correctly.

Scale is not a problem in auto cooling systems because you are not boiling water and you are generally not using make up water. If your tap water is soft you can use that no problem.
 
Originally Posted by willbur
Originally Posted by das_peikko
Distilled water pulls minerals out of the engine block? Boy that does it right there. I've heard everything now.
lol.gif



MB, years back, did say Not to use distilled water in their engine coolant because of metallic leaching. May have changed by now because of different cooling system metallurgy since then. I do know deionized water is very aggressive and is sometime used for cleaning. Maybe this is where the "hungry" water theory originated.


Interesting, have a link to an FSM that says that?

MB Sheet 310.1 says:
Quote
Water quality

Clean and the softest possible water should be used for processing the coolant. Drinking water often satisfies the requirements. Information concerning the water quality of drinking water is available from the local water-plant authorities or the official water utilities on request.

If there is no available information regarding the water quality or if no suitable water is available, then distilled or deionized water should be used to prepare the coolant. Sea water, brackish water, brine and industrial waters are not suitable. Salts may promote corrosion or form disruptive deposits.


https://bevo.mercedes-benz.com/bevolisten/310.1_en.html
 
Take the popular 50/50 coolant … what water did Prestone (or whom ever) mix for that jug?
 
Originally Posted by JHZR2
Originally Posted by willbur
Originally Posted by das_peikko
Distilled water pulls minerals out of the engine block? Boy that does it right there. I've heard everything now.
lol.gif



MB, years back, did say Not to use distilled water in their engine coolant because of metallic leaching. May have changed by now because of different cooling system metallurgy since then. I do know deionized water is very aggressive and is sometime used for cleaning. Maybe this is where the "hungry" water theory originated.


Interesting, have a link to an FSM that says that?

MB Sheet 310.1 says:
Quote
Water quality

Clean and the softest possible water should be used for processing the coolant. Drinking water often satisfies the requirements. Information concerning the water quality of drinking water is available from the local water-plant authorities or the official water utilities on request.

If there is no available information regarding the water quality or if no suitable water is available, then distilled or deionized water should be used to prepare the coolant. Sea water, brackish water, brine and industrial waters are not suitable. Salts may promote corrosion or form disruptive deposits.


https://bevo.mercedes-benz.com/bevolisten/310.1_en.html



I do not have a link to this info because it was years ago. It was a technical article in one of the reputable/trusted car magazines.
 
So nothing in that MB sheet says anything about not using distilled water, in fact it lists a maximum hardness level for the water that should be followed. If you don't know the hardness level or it exceeds the given value then you should use distilled or deionized water instead. Note the statement about "softest possible water". More Internet amplification of misguided notions about this subject.

When I lived in the City of Milwaukee we had extremely soft water as do many individuals who obtain their drinking water from surface supplies. But here in the suburbs were the water comes from deep wells our hardness value makes it entirely unsuitable for cooling systems and the value greatly exceeds the one listed in that sheet.

"Technical article in one of the reputable/trusted car magazines" explains how they too misinterpreted the sheet and subsequently promulgated the incorrect information to the general public. So the bottom line is that "MB, years back, did say Not to use distilled water in their engine coolant because of metallic leaching." is in reality nowhere to be found in any MB technical information.
 
Originally Posted by kschachn
So nothing in that MB sheet says anything about not using distilled water, in fact it lists a maximum hardness level for the water that should be followed. If you don't know the hardness level or it exceeds the given value then you should use distilled or deionized water instead. Note the statement about "softest possible water". More Internet amplification of misguided notions about this subject.

When I lived in the City of Milwaukee we had extremely soft water as do many individuals who obtain their drinking water from surface supplies. But here in the suburbs were the water comes from deep wells our hardness value makes it entirely unsuitable for cooling systems and the value greatly exceeds the one listed in that sheet.

"Technical article in one of the reputable/trusted car magazines" explains how they too misinterpreted the sheet and subsequently promulgated the incorrect information to the general public. So the bottom line is that "MB, years back, did say Not to use distilled water in their engine coolant because of metallic leaching." is in reality nowhere to be found in any MB technical information.


Thank you for clearing that up. I wondered about this for years. However, it appears you/someone cite a recent (?)MB tech sheet. Perhaps the recommendation that I found applies to earlier MBs and not more recent vehicles? Did you research ALL MB tech sheets going back? We all know recommendations do change over time because of material and chemistry advances. Maybe MB did recommend not to use distilled water?

I am not trying to get into a match. LOL Just trying to educate myself
 
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Does any one run pure distilled water in their coolant system? Most run a 50/50 or so mix.
 
Power station we do...
The steam circuit I'd deionised with continuous full flow polishing through ion exchange. A few ppm of ammonia and hydrazine....then up to 2600 psi and 320c

The generator stator is made of copper brass and steel, and is cooled again by ultra pure water, continuously kept that way with mixed resin polishing...has to be pure enough that the 22,000 volt 660MW electricity doesn't leak to ground.

THAT water is cooled by another demineralised water system, again mixed metal.

All these systems running ultra pure water last 300,000 hours in service.

That's why I find these scary threads so amusing...
 
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Originally Posted by willbur
Originally Posted by kschachn
So nothing in that MB sheet says anything about not using distilled water, in fact it lists a maximum hardness level for the water that should be followed. If you don't know the hardness level or it exceeds the given value then you should use distilled or deionized water instead. Note the statement about "softest possible water". More Internet amplification of misguided notions about this subject.

When I lived in the City of Milwaukee we had extremely soft water as do many individuals who obtain their drinking water from surface supplies. But here in the suburbs were the water comes from deep wells our hardness value makes it entirely unsuitable for cooling systems and the value greatly exceeds the one listed in that sheet.

"Technical article in one of the reputable/trusted car magazines" explains how they too misinterpreted the sheet and subsequently promulgated the incorrect information to the general public. So the bottom line is that "MB, years back, did say Not to use distilled water in their engine coolant because of metallic leaching." is in reality nowhere to be found in any MB technical information.


Thank you for clearing that up. I wondered about this for years. However, it appears you/someone cite a recent (?)MB tech sheet. Perhaps the recommendation that I found applies to earlier MBs and not more recent vehicles? Did you research ALL MB tech sheets going back? We all know recommendations do change over time because of material and chemistry advances. Maybe MB did recommend not to use distilled water?

I am not trying to get into a match. LOL Just trying to educate myself


Believe Daimler Benz has been using a low silicate HOAT since the late 70's. G-05 was it, now they have G-48 on the list, which I'm not happy about because it has 2-EH in it... but otherwise very much the same...
 
Originally Posted by 4WD
Take the popular 50/50 coolant … what water did Prestone (or whom ever) mix for that jug?


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Originally Posted by CT8
Does any one run pure distilled water in their coolant system? Most run a 50/50 or so mix.


I know a guy with a old Kubota that does. Straight water in the summer. 50/50 in the winter. I've thought about trying it when I have nothing better to do.
 
Originally Posted by dlundblad
Originally Posted by CT8
Does any one run pure distilled water in their coolant system? Most run a 50/50 or so mix.


I know a guy with a old Kubota that does. Straight water in the summer. 50/50 in the winter. I've thought about trying it when I have nothing better to do.


Not really sure why one would want/need to if the system was sized appropriately. If the Kubota overheats in hot weather, why not track down the problem?

The issue with straight water is that I'd doesn't have any inhibitor at all. That's a different conversation then distilled vs deionized vs tap. I get wanting to do away with the glycol for heat transfer reasons, but would argue that the other adds are still necessary, and to swap every year and replenish them seems like a waste of $ unless the mixes are being stored in inert containers for the next year.
 
Originally Posted by JHZR2
Originally Posted by willbur
Originally Posted by kschachn
So nothing in that MB sheet says anything about not using distilled water, in fact it lists a maximum hardness level for the water that should be followed. If you don't know the hardness level or it exceeds the given value then you should use distilled or deionized water instead. Note the statement about "softest possible water". More Internet amplification of misguided notions about this subject.

When I lived in the City of Milwaukee we had extremely soft water as do many individuals who obtain their drinking water from surface supplies. But here in the suburbs were the water comes from deep wells our hardness value makes it entirely unsuitable for cooling systems and the value greatly exceeds the one listed in that sheet.

"Technical article in one of the reputable/trusted car magazines" explains how they too misinterpreted the sheet and subsequently promulgated the incorrect information to the general public. So the bottom line is that "MB, years back, did say Not to use distilled water in their engine coolant because of metallic leaching." is in reality nowhere to be found in any MB technical information.


Thank you for clearing that up. I wondered about this for years. However, it appears you/someone cite a recent (?)MB tech sheet. Perhaps the recommendation that I found applies to earlier MBs and not more recent vehicles? Did you research ALL MB tech sheets going back? We all know recommendations do change over time because of material and chemistry advances. Maybe MB did recommend not to use distilled water?

I am not trying to get into a match. LOL Just trying to educate myself


Believe Daimler Benz has been using a low silicate HOAT since the late 70's. G-05 was it, now they have G-48 on the list, which I'm not happy about because it has 2-EH in it... but otherwise very much the same...


You can get G-48 without 2-Eha, although it is rare, but i can source one locally which at least does not mention 2-Eha in the SDS
 
Originally Posted by Shannow
Power station we do...
The steam circuit I'd deionised with continuous full flow polishing through ion exchange. A few ppm of ammonia and hydrazine....then up to 2600 psi and 320c

The generator stator is made of copper brass and steel, and is cooled again by ultra pure water, continuously kept that way with mixed resin polishing...has to be pure enough that the 22,000 volt 660MW electricity doesn't leak to ground.

THAT water is cooled by another demineralised water system, again mixed metal.

All these systems running ultra pure water last 300,000 hours in service.

That's why I find these scary threads so amusing...


Correct me if i'm wrong, but don't they sell Corrosion Inhibited water in OZ for cars?
That would be interesting to try.
 
Yep, you can get a green coolant which is corrosion inhibited, with no glycol.

Castrol used to sell a small can of "green" about 150ml which turned water into coolant (again with no glycol)
 
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