Or you find a company that has this instrument and hire them to do an analysis. You don't need to buy the instrument.

 

I find the discussion about distilled water versus RO plant water somewhat interesting. Distilled water is extremely aggressive and is crying out for ionic content- it is the nearest thing to a universal solvent! At one stage in my career my client was Exxon in the UK. One of my colleagues had a project that involved a section of austenitic stainless steel piping that had to be hydrotested after welding and the test specification called for water with a chloride content less than specified value [austenitics are vulnerable to chlorine attack]. The engineer involved instinctively ordered a tanker of distilled water to meet the hydrotest spec requirement. The test was successful and the water was left in the system. 48 hours later parts of the piping resembled a watering can! The distilled water had gone through the stainless piping like a knife in through butter.

I would politely suggest that demineralised water out of an RO plant is a far safer bet than distillled water. The reason distilled water is no longer commonly available is because car batteries are invariably sealed and no possibility of topping them up as we used to in days gone by.. What are commonly referred to as water softening units these days are in fact mini RO plants- just not very efficient. With carbon filters they actually get more out of the water than a flash desalination unit does, the main difference being that a flash unit gets rid of all mineral content and therein lies the potential problem.

 

It's readily available in every grocery store, at least in Wisconsin.

I have 10 gallons on the shelf in my garage, used to dilute chemicals for car detailing. I have no idea what anyone else uses it for.

In stock even at the local hardware store. 454 gallons at just one of the 3 Menards stores in Green Bay:
https://www.menards.com/main/grocery...4451353936.htm

 

Eric,

My intent was to convey why the stuff is not as common as it used to be in automobile accessory shops.- should have have made that clear. That it is still commonly available there is no doubt.

 

I've been keeping a stock of the stuff in my garage for as long as I can remember (25+ years rough guess) and I've never bought it at an automotive parts store. The bulk concentrate detailing chemicals I dilute with distilled water are not available at any auto parts stores either, at least around here. Some of them are sold at the Sherwin Williams Automotive Store, which doesn't carry distilled water either.

None of the car batteries in my fleet are sealed either, two of them purchased last year, Interstate brand.

Apologize if I missed your point, but earlier it was suggested that steam generated distilled water may be more difficult to come by versus di-ionized water and it sure seemed like you were on that angle of the subject.

No harm no foul, carry on.

 

Before we all get brain-damge treading onto the deep end, I figured we all benefit getting the basics out of the way. Here's a major difference between distilled water and deionized water.

https://bescocommercial.com/blog/dei...-vs-distilled/

 

Sorry @HenryPcar I vote for more brain damage. Your link describes both distilled and DI water as 'safe to drink.' Yet there are many, many other references (including my wife who knows her $h1+ about this stuff) that contradict that statement as a simple truth:

https://www.thoughtco.com/is-it-safe...d-water-609428

And if you don't believe that:

https://en.wikipedia.org/wiki/Purifi...purified_water

That wiki page is really interesting. Distilled and deionized in terms of language use is most-correctly a reference to the process used to produce purified water: they are both forms of 'purified water.'

@FredR I completely believe your story about the pipes being eaten.

The whole 'water' part of this thread started due to these two posts:

Dr B's

https://rennlist.com/forums/928-foru...l#post16191514

"it's starved for ions when the process is complete"

my reply:

https://rennlist.com/forums/928-foru...l#post16193293

... in which I posted "Deionized water leaches metal."

Both Dr B's and my above statement are more-or-less true. But there's one *very* critical "truth" that was not considered initially: Distilled water is completely free of ions - it's more-pure than DI water - except for stray H- and H0+ which is what makes distilled water so 'hungry' for ions from the stuff it touches.

So, the whole DI versus Walmart's water is a red herring unless we want to disbelieve every single coolant manufacture's recommendation to dilute 'pure' coolant with distilled water.

Now for more brain damage:

On the flip side this does suggest that flushing your cooling system with distilled water (with or without a flush agent) is perhaps disrecommended. I note that the instructions page for Prestone Radiator Flush does not specify distilled water

https://prestone.com/products?detail=AS105Y (instructions tab)

while the page for their coolant does:

https://prestone.com/products?detail=AF2000

But, unless your tap water is nicely soft, we know that using tap water will leave mineral deposits. So maybe if you are flushing the system (note *not* "filling" the system) you should use 'lightly' deionized water.

There....

I'll just leave that here and go back to the shop and work on 928s. (There might be a more-on-topic reply later.)

 

I’m going to church this Sunday and am stocking up on even better stuff....

 

OK, I'm going back to lightly ionized tap water!

 

I'm comfortable following the coolant mfrs' guidelines and diluting with distilled water. There are sufficient buffers in the coolant to protect the aluminum, based on the mfrs' info. They are smarter than I am on their products. Manage pH at sufficient (non-acidic non ion-starved) levels and you should be fine.

A certain amount of the additive package is intended to capture and bind the dissolved minerals in the water. I get a report a couple times a year from the local water utility, telling about the various mineral contents in the tap water they deliver. We happen to have very soft water out of the tap, but the Total Dissolved Solids and the calcium fraction of those is higher than I like for engine cooling in aluminum. I may cold-flush with hose water, but no heating until the fill is distilled water or a blend with coolant.

When I did a coolant service early in my stewardship period, I was hesitant to pull hard on the block drain bolts. So I did a soft-water hose-flush, and put coolant on top of that. By the next change, the support group here gave me enough confidence to pull harder and get the block completely drained. That allows pretty complete draining, and replacement with a distilled-water blend is pretty reliable. At this point there have been no signs of minerals plating out in the radiator or the inspectable sections of the block. Water bridge and thermostat housing are clean, and no deposits looking through the block drains. Most of the minerals that are captured and contained by the additives end up as rocks or plate-out in colder sections of the system, and are easy to find in the bottom of the radiator and the galleys.

Local hot-spot boiling in the system is another thing that might cause minerals to plate out in odd places. That process also involves some mechanical erosion of the local surfaces, as the coolant erupts into steam bubbles, then the bubbles collapse again back to liquid. There's some thermal shock too as energy moves rapidly back and forth across a small area. The damage seen around the fire rings in Jim's engine could easily be caused by local hot-spot boiling erosion rather than chemical corrosion.

 

Just posting this because I stumbled across the sheet below tonight. For those that may be considering Glysantin G-48 but not dig'n the shipping cost to the US. Apparently it's the same as Zerex G-48 which can be found at NAPA, O'Reilly's, etc. BTW - Who knew they had a shelf life of 3 years(?)

Unrelated, I feel like a pig looking at a watch when I look at the different datasheets. For the smart cookies, what does it mean when G-05 has an aluminum loss of 1.8mg in simulated service test and G-48 has a gain of 1.2mg?

G48: http://www.geomatique-liege.be/MGJP/...santin_G48.pdf

G05: http://www.geomatique-liege.be/MGJP/...santin_G05.pdf

 

The tests are designed to give a performance indication measure of what might happen in service. A positive loss is expected and the figures posted show what is considered acceptable and what is actually demonstrated in the lab. The actual numbers are very small compared to what is considered acceptable and in some cases a weight gain was recorded [negative value as they were assessing loss- a vector quantity- ha ha!] in the test. Why such happened is not clear but obviously it is not relevant.

Interestingly make up water as per their determination only needs to be softish which by most standards means less than 200ppm TDS supporting the notion I alluded to earlier in that mineral content of the make up water is not too critical- at least for these products.

In my first post to this thread I stated that there was nothing to support the notion that the coolant was responsible for Jim's corrosion other than the fact that it was present and I am still of the opinion that is very much the case and that some other mechanism has caused the corrosion experienced.

 

Just to muddy the water/coolant debate a bit more. The info quoted comes from the Internet, so it must be true !!!

"While both deionised water and distilled water can be safely used on metal parts in automotive systems, deionised water can be more corrosive than distilled water because it more readily absorbs carbon dioxide from the atmosphere.Jul 5, 2019"

Right or wrong, this was also my understanding for some years now. (BTW, chemistry was not my favorite subject in school and I am a self-declared chemistry idiot)

 

Damn, so another thing to worry about? A shelf life, like brake fluid. That's it, I'm out, Blumaxx for sale and I'm switching to leasing new Honda Accords every 2 years

 

And people wonder why EVs are getting more popular by the day. The next generation would really wonder how in the world we all put up with the complexity of ICE vehicles.