Car radiator coolant instead of water?

magda

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I'm upgrading my watercooling setup and I'm wondering about using car radiator coolant instaed of water.
The idea is to avoid copper corrosion.

There are different engine coolants, like:
IAT (Inorganic Additive Technology)
OAT (Organic Acid Technology)
HOAT (Hybrid OAT)

Which one would be more adecuate for a copper loop?
And as these coolants have dyes, that could also leave some residue after a while...
 

pendragon1

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get the regular green stuff and mix it like 90/10 distilled water to coolant. thats all they use in aios and what i use to refill mine.
 

Zarathustra[H]

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These are pretty much just premixed water/antifreeze solutions right?

Antifreeze used to be very popular back in the early days of water cooling, before there was an industry to support it, when people where modding their own shit.

Antifreeze is usually glycol based, and glycol is very popular in atercooling coolants.

In the correct concentrations it does all three things you want your water cooling fluid to do:

It has:
- Anti-corrosive properties
- Anti-growth properties
- Surfactant properties.

There are certainly a lot worse things you could use.

Only caution I would have is that it is unclear to me what the other ingredients in these formulations might be, and what they might do.
 
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Just be sure not to use any glycol coolants in a loop with PETG. It will melt the tubes.
 
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Zarathustra[H]

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Just be sure not to use any glycol coolants in a loop with PETG. It will melt the tubes.

I'm trying to remember the details about this, but it is surprisingly difficult to find by googling.

As I recall one of the common glycols (ethylene glycol, or propylene glycol) is fine for use with PETG, but the other causes trouble.

I just can't remember, and I can't find anything while googling right now.
 

matt167

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propylene I think is 'ok' to use, which I think is the same formulation as PETG I think.. Many RV antifreezes will be propylene while some are alcohol based. BUT, unless going hard tube/ probable high dollar build, antifreeze will be fine

I don't think they will stain anything, and you can choose almost any color.. Green, yellow, red or blue. You'll find some purple windshield washer fluids if that's your color, just make sure it's glycol based and not alcohol
 

VoodooRufus

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I run ~75/25 water to antifreeze to make sure I have enough biological and corrosion inhibitors. Works great for years.
 
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THRESHIN

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No corrosion inhibitor or biocide in distilled. Growth won't be removed by a coolant change, and corrosion can be irreparable if severe enough.

So long as you don't use dissimilar metals in your loop corrosion is not a problem. Many of my parts are 15 years old or more.

A biocide additive doesn't need to be extreme like antifreeze. A simple additive with that purpose will do. I bought a little bottle of PTnuke when I built this setup and I still have it. Couple drops is all it takes.

Sure if you want say a copper block and an aluminum rad in your loop, corrosion is a huge concern. Not sure why you'd want to bother though.

So sure car coolant will do the job. Kind of like throwing a hand grenade at a fly. It's stupid overkill and antifreeze is very toxic stuff. If it leaks, I'd rather it not be in my home thanks.
 
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So long as you don't use dissimilar metals in your loop corrosion is not a problem. Many of my parts are 15 years old or more.

A biocide additive doesn't need to be extreme like antifreeze. A simple additive with that purpose will do. I bought a little bottle of PTnuke when I built this setup and I still have it. Couple drops is all it takes.

Sure if you want say a copper block and an aluminum rad in your loop, corrosion is a huge concern. Not sure why you'd want to bother though.

So sure car coolant will do the job. Kind of like throwing a hand grenade at a fly. It's stupid overkill and antifreeze is very toxic stuff. If it leaks, I'd rather it not be in my home thanks.
I never said car coolant was a good option. I only said that straight distilled with no additives isn't a good one either.
 

THRESHIN

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I never said car coolant was a good option. I only said that straight distilled with no additives isn't a good one either.

That is correct. You also mentioned distilled not having corrosion inhibitor. This gives the impression that it is necessary. The point of my post was that if you are not using dissimilar metals in the loop a corrosion inhibitor is unnecessary and that there are options for biocide.

Anything else I can clear up for you?
 
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Anything else I can clear up for you?
Yeah: why are you even arguing with me in the first place? We both agree that running pure distilled isn't a good idea, and we both agree that automotive coolant, while it will work, isn't great either. If you've run for forty+ years without inhibitors and not had any corrosion in your loop, then congratulations on Being Very Smart and Not Needing Corrosion Inhibitors. Personally I'd rather not gamble. Copper, brass, nickel and stainless are not dissimilar, but they are also not identical on the anodic index, so I prefer to run an inhibitor and suggest others do as well.
 
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Nimisys

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PC water cooling I swear is intent on reinventing the damn wheel.

A gallon of GM High Voltage Battery coolant runs about 10$. It is a 50/50mix of antifreeze and Distilled Water intended to keep the the battery pack as well as the AC/DC inverter, Motors, motor controllers, and DC/DC inverters all cool, with a lifespan of 10yrs, under both higher thermal loads and pressure.

So what about it isn't great for PC cooling again? Not specialized enough? Any leak great enough to pose a health hazard due to toxicity is going to have to be quite substantial, way past the point of your equipment already being dead.
 
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Any leak great enough to pose a health hazard due to toxicity is going to have to be quite substantial, way past the point of your equipment already being dead.
You must not have pets or small children.

Ethylene glycol is sweet tasting and highly toxic.
 

Nimisys

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You must not have pets or small children.

Ethylene glycol is sweet tasting and highly toxic.
I have both, and you obviously don't have much exposure. For the last twenty years, anti-freeze
has contained bittering agents. The initial half second, it will taste sweet, but the bittering agent is strong and last about 15-20mins from a single drop. They have also reduced the toxicity from previous levels. As a mechanic, I am exposed to the stuff daily.
 
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I have both, and you obviously don't have much exposure. For the last twenty years, anti-freeze
has contained bittering agents. The initial half second, it will taste sweet, but the bittering agent is strong and last about 15-20mins from a single drop. They have also reduced the toxicity from previous levels. As a mechanic, I am exposed to the stuff daily.
If those facts make you comfortable with keeping the stuff around, then the risk level is acceptable to you - it isn't to me. Mainly because there are products on the market that achieve the same thing in my loop and aren't toxic. I keep a fill bottle handy in my office so it's worth it for me for the stuff to be non hazardous.
 

Nimisys

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Copper sulfate in PT Nuke is also toxic, in sufficient quantities. For as often as things need topped off, it's not like you have to keep it immediately available. You don't have an issue keeping bleach around somewhere do you? Or ammonia? That's far more toxic than anything being discussed here.
 

THRESHIN

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Yeah: why are you even arguing with me in the first place? We both agree that running pure distilled isn't a good idea, and we both agree that automotive coolant, while it will work, isn't great either. If you've run for forty+ years without inhibitors and not had any corrosion in your loop, then congratulations on Being Very Smart and Not Needing Corrosion Inhibitors. Personally I'd rather not gamble. Copper, brass, nickel and stainless are not dissimilar, but they are also not identical on the anodic index, so I prefer to run an inhibitor and suggest others do as well.

Ok point well taken. My apologies.
 

Gideon

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Distilled and silver kill coil is all I have used, but I change the water every 6 months and have no issues.
 
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VoodooRufus

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Distilled water by itself is a straight path to clogging up your blocks with growth. The silver kill coils are inadequate to prevent it, too. Running 25% glycol is enough to kill anything, without being high enough to be a detriment to heat transfer to matter.
 

Gideon

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Distilled water by itself is a straight path to clogging up your blocks with growth. The silver kill coils are inadequate to prevent it, too. Running 25% glycol is enough to kill anything, without being high enough to be a detriment to heat transfer to matter.

Been 6 years and counting and the blocks have been fine. Long as you change the water from time to time there is truly little risk.
 
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tunatime

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Been 6 years and counting and the blocks have been fine. Long as you change the water from time to time there is truly little risk.
I 100% guarantee you have bacteria growth in it and probably some algae it's just limited by how much nutrients are in the water. Why not add something so you don't have to drain it ever 6 months? I doubt anything you can add to it that a pump can still pump will hurt temps more then a few c
 

Gideon

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I 100% guarantee you have bacteria growth in it and probably some algae it's just limited by how much nutrients are in the water. Why not add something so you don't have to drain it ever 6 months? I doubt anything you can add to it that a pump can still pump will hurt temps more then a few c

I can 100% guarantee I dont since I took it apart when I upgraded to the 3900X from my 1700X and it was just fine. On a closed loop a silver kill coil is more then enough unless your using tap water or something like that. I drain every 6 months because by then the case needs a good cleaning and it's super easy to drain and fill with the way I put it together. Seems to work well for me since it's still cooling just the same as when I put it all together, I just dont feel the need to complicate it by adding coolant to it.
 
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I respect all of you guys, especially the ones that have been doing custom loops forever. However, I have to say that at this point in the game there is little point in debating a dead issue. Distilled water with a biocide works very well but needs to be changed more often. Distilled water with just a kill coil works in most cases, but is just not recommended anymore. Clear concentrates or premixes are now really awesome and if you want the very least hassle, and best results get a clear premix. Premix with dye , of the same brand, is your next best hassle free option. This would involve filling your loop with clear and then using a dye to drop in some color. If you want to roll the dice a bit try a premix color option. Obviously the deeper the color the more "staining" you can expect. Dark red is going to, possibly, give more problems than white. In my builds I have generally used either clear or light pastell colors and have never had a problem with "gunk" or staining. Then again, I have never reused tubes in builds. The real issue is will your res or block get stained. I am telling you they will not as long as you use modern liquids made for this and quality reservoirs and blocks. Should you use automotive products? No! Why would you. Clear premixes are not expensive, and pc water cooling pumps are not near as strong as car pumps. Just get a clear premix and stop trying to out think the room. That premix is designed to avoid corrosion!
 
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