Best suited antifreeze for aluminium engines/cooling systems?

[Astro14]

The 1992 300E manual is quite similar in its wording, stating that for adding water, the water must be of sufficient quality, and that it must be “treated” if it is not.

Here‘s the screenshot.

 

[Astro14]

And the S600 says the same thing…“minimum requirements, which are usually satisfied by normal drinking water”…

 

[Astro14]

So, water added to a Mercedes cooling system is not required to be distilled, as the Bevo sheet already said, and I already posted, but it must have no more than a certain concentration of dissolved salts. No more than.

I am still looking for a document, from a manufacturer, that says it must have a minimum of XX concentration of calcium, etc, that drinking water would have.

In other words, a prohibition on distilled.

Let me know if you can find that “Mercedes Tech article”

 

[kschachn]

I posted this in the hope of finding out, not to go toe to toe with someone about it. I use distilled water in all my cars. Some how this question about the actual chemistry is elusive. Just want to know- Does distilled/deionized water leach metals out of coolant systems?

I've answered that twice in this thread. Yes it does. Water has a certain solubility for metal ions, and since distilled and deionized water has no metal ions then it will dissolve metals. But that solubility is finite and in a closed system such as a cooling system the amount of metal it will dissolve is in the micrograms. This behavior is not limited to distilled or deionized water however, some water has quite a bit of dissolved iron but perhaps no aluminum. That water will dissolve exactly as much aluminum as will deionized or distilled water.

The problem that people on the Internet misunderstand and mischaracterize is that it's only an issue where freshly distilled or deionized water is continuously flowing over a surface. In the corporate research laboratory I worked in we had a water purification system and of course we had to keep metallic piping or surfaces away from that water for two reasons. One is that we didn't want the water to become contaminated with metals and second, over the course of many years it could attack the piping. But this "attack" does not happen the same way in a closed system since the water quickly becomes saturated with whatever metal it contacts and is therefore no longer dissolving the metal.

It is even less of a concern when an appropriate coolant is used since the coolant contains passivation agents that help prevent corrosion. But even here that's not due to the deionized or distilled water, it is due to precipitates forming that fall out of solution and expose fresh bare metal surfaces. This type of corrosion is prominent even with tap water and is why no one should ever use plain water in a cooling system.

No automobile manufacturer that knows even the slightest chemistry would prohibit the use of distilled or deionized water when mixing with a coolant.

 

[kschachn]

So, water added to a Mercedes cooling system is not required to be distilled, as the Bevo sheet already said, and I already posted, but it must have no more than a certain concentration of dissolved salts. No more than.

I am still looking for a document, from a manufacturer, that says it must have a minimum of XX concentration of calcium, etc, that drinking water would have.

In other words, a prohibition on distilled.

Let me know if you can find that “Mercedes Tech article”

And this makes complete sense. Because the consumer may not know specifics about their water supply then the easiest and clearest course of action is to used deionized or distilled water.

 

[willbur]

I’m interested - but you’re asking me to accept, as fact, an opinion, a self-admitted controversial opinion, relayed from the author of an article in a car magazine, from 12 years ago, that refers to a tech publication that no one seems to be able to find?

Though I accept your quote as genuine, and believe that you found it as is, and while I appreciate the work, it‘s lacking the manufacturer recommendation I was seeking. I don’t know the author’s experience or credentials, so, it remains opinion.

If we could find the elusive “Mercedes tech publication” from 20-25 years prior to 2009, to which the author refers, and to which you’ve referred, that would be a good start.

If we could find something current, from a manufacturer, recommending against the use of distilled water, then, that would be even better.

I‘m willing to read, to listen, to change my mind, but it has to be because the facts are there.

Astro- what do you need to be comfortable? He references a M-B tech article as I do. Two independent sources. Good enough for me. I'm satisfied. I'm not about to scour the i-net to provide additional info. Its not worth it to me to prove you right or wrong. If you feel so strongly about this "tempest in a teapot" - go for it. Regarding authors experience or credentials, the same can be said here for the other posters.

Over 1000 views! Lets take a vote. BITOG - who do you think is correct? Astro, me or ? LOL

 

[kschachn]

You have one vague reference from a third-party to a statement that isn’t even verified. And you’re asking whom you think people believe?

Perhaps you could spend some time showing that my answers to you are incorrect. You seem to be invested in that idea.

 

[willbur]

You have one vague reference from a third-party to a statement that isn’t even verified. And you’re asking whom you think people believe?

Perhaps you could spend some time showing that my answers to you are incorrect. You seem to be invested in that idea.

Really K- you are complementing yourself- I simply don’t care about your implied idea. Just being sucked into your game of endless posts. Over something no one cares about…

Bring on the vote!!

 

[Mazomopar]

So just a thought here and it's probably been brought up,but what do the antifreeze companies add to their concentrated solutions to make it a 50/50 blend in their retail jugs.

 

[kschachn]

Really K- you are complementing yourself- I simply don’t care about your implied idea. Just being sucked into your game of endless posts. Over something no one cares about…

Bring on the vote!!

That’s just bizarre. You make the posts asking and asking, and when answered you get snarky… again. Well at least others in this thread can read what’s posted and learn.

 

[Snowflake White]

It would be more interesting to see the original German owner's manuals or service manuals for these cars back in the 1970s and 1980s.
Many times the information is translated from the original language and at times the meaning isn't related correctly. I've found this true in VW manuals when looking at the difference between the original in German and the translated for other markets in English.
Often times the German manuals will be much more detailed and specific about things too.

 

[NashNative]

Reading that link you posted, on page 3 clearly says that OAT is the best coolant out of conventional/hybrid-hoat/oat. That is quite interesting.

Hi everyone, I helped put that article together. I would be glad to help answer coolant questions you guys have...let me know!

 

[nthach]

For a Mercedes, all you really is need G-05 or G-48(all models are backspeced for the new stuff but I’d stick to G-05 in pre-2000s models) and distilled water. Easy.

IME, all the things I’ve touched that has seen only OEM-spec coolants had clean coolant passages. It’s when you mix coolant chemistry(IE adding Dex-Cool/Dex-Clone to old school green silicate-phosphate coolant or vice versa) or use hard water is when you have problems. The OEMs are now all in on OAT inhibitors, with the Japanese/Koreans and Ford using pHOATs(Prestone Cor-Guard is the 2-EHA variant of the benzoate/sebacate Japanese variety) and the Europeans/Tesla using SiHOAT(G-05/40/48) coolants; GM/Stellantis being the last holdout for straight OAT.