Antifreeze shenanigans

[FishFry]

Last night I had a long discussion with some friends on antifreeze.
I was amazed how many opposite opinions I heard on something that should have a pretty straight answer.

Ethylene, propylene, organic, inorganic, silicates, long life, distilled, non-distilled, bolt in zinc anodes andwhatnot.

Some say propylene based doesn't kill your bearings, when it gets into the oil, but it kills your seals on older engines (also silicone form-a-gasket stuff).
Some say distilled/demineralized water is corrosive and eats your engine, others say tap water makes deposits and scaling, and that some instructions say to use distilled water.

Everybody says they did this or that for 150 years (pretty much every possible combination) and never had a problem at all,
than the mechanics chime in and tell stories about leaking disasters with a certain orange type of antifreeze, they had to fix all the time etc.

The information you can find online is also all over the place and it's a mess.

I'm not a chemist, all I know for sure is that you should not mix different types, since they may gel.
On my daily drivers (most of the time 10-20 year old cars) I actually never gave it much thought. Always used the recomended type and tap water and called it a day. Also never had a problem with that. Maybe that means it's not THAT critical at the end of the day - who knows?

Can someone with more knowledge please shine some light on this?

I'm having a 41 Chevy with a hopped up 261 - iron block and head, but aluminum intake (water heated) and a radiator with brass parts.
It's a mixed bag of metals. Also sometimes our winters get pretty cold, so just Water Wetter doesn't do the trick.
Distilled/demineralized water or tap water? Organic/inorganic? Ethylene, propylene, silicates free?
And what's the deal with those anodes? Do I just throw a magnesium stick on the radiator?

thanks, Frank

 

[Thunderbolt]

I would also like to know more about this antifreeze jungle.

My brass heater core started leaking, iron block and heads, aluminum intake and radiator.
I read that some "modern" types of antifreeze can be bad for brass (or maybe the solder tin?).
I used "modern" OAT antifreeze, could be the issue, or that the heater core was from 1967, who knows

The replacement heater core was made of aluminum, so i filled with OAT anti freeze again.

 

[Grumpy]

Best Antifreeze and Coolant Fluids for 2022

Antifreeze prevents engine cooling fluids from freezing in winter and helps cool the engine in summer. Here are the best antifreeze and coolant fluids for 2022.

www.forbes.com

The 10 Best Coolants and Antifreezes

Find out how to choose the best engine coolant and antifreeze for your car based on factors such as quality, price, performance, warranty and more.

mechanicbase.com

The Best Antifreeze (Review) in 2022

Car's cooling system is vital for a smooth engine performance. Check out our detailed guide about the best antifreezes on the market to save you time and money.

www.carbibles.com

Best Antifreeze: That's Cool

Antifreeze, or coolant, is vital to making sure your car runs properly. Check out the best antifreeze at The Truth About Cars.

www.thetruthaboutcars.com

Best Antifreeze: Keep Your Engine Cooler for Longer

Looking for antifreeze? Our team of experts narrowed down the best antifreeze on the market. Read this review and save yourself time and money.

www.thedrive.com

Choose the Right Engine Coolant - Valvoline™ Global

Learn about the different types of engine coolant and make sure you're putting the right coolant in your vehicle. Valvoline's antifreeze color chart can help!

www.valvoline.com

thoughts on cooling

read this, yes theres a good deal of info in the links worth the time and effort, and yes its well worth your time to read thru keep in mind, that if your engine is mechanically functioning correctly, IE there are no problems like leaking head gaskets or the wrong head gasket or a cracked head...

garage.grumpysperformance.com

anti freeze red vs green

ANY ANTI FREEZE needs to be replaced every 3-5 years or so or at 150K miles ,AS A MAXIMUM LIFE EXPECTANCY, MOST LOSE SIGNIFICANT LEVELS OF EFFECTIVE CORROSION PROTECTION GRADUALLY FROM 24 MONTHS and about 40,000 miles and its a good idea to have the RADIATOR FLUSHED of the crud that tends to...

garage.grumpysperformance.com

14 Rules for Improving Engine Cooling System Capability

I thought this article explained very well why slowing down the flow of coolant by using a restriction is wrong. Also goes a long ways to uncovering many of the myths that surround a cooling system. Mr Crook gives us some hard numbers that can be used when picking a radiator, such as the number...

garage.grumpysperformance.com

anodes

I got asked if USING anodes, in an engine is a good idea? electrolysis can rapidly cause damage, use of a 50% anti-freeze/50% water coolant mix and at least two good separate engine grounds to the cars frame helps but get out a multi meter and test for voltage in coolant, (more info in links)...

garage.grumpysperformance.com

 

[FishFry]

Thanks for the links Grumpy,
this here also answered a lot of my coolant questions:

No-Rosion Products Technical Questions and Answers

Frank

 

[Indycars]

Using ANODES is a good idea also. I have two in my TBucket, one in the bottom of the radiator and one in the back of the intake manifold. It's not one and done either, anytime you have the system open you should check it if it's been over a year since the last time.

 

[FishFry]

Actually this is the first time I hear about anodes in cars ever.
So they are in my car from the factory? Where are they?
Should I check them from time to time? Are they already eaten away after 20 years?
Why haven't I heard of them the last 50 years?

Frank

 

[Grumpy]

factory cars in some cases came with them, on others , they were not there,
but in all cases they (ANODES) provide better durability and reduced corrosion, in the cooling system.
keep in mind factory cars are built with PLANED OBSOLECENCE in mind
, I.E. about the time you have the car paid off (6-7 years old) minor parts are expected, and designed to start wearing out.
now parts like brakes, light bulbs, fan belts, filters, batteries, water pumps, power steering pumps, tires, shocks constantly wear out every few years or every 15k-30k miles
but parts like transmissions, radiators, u-joints also generally wear out every 80k-150k miles, the idea the manufacturers depend on, is that most people will just get frustrated after a few dozen parts are replaced, and start over by buying a new car./truck
thus cheap and easily added parts that add minimal cost but also extend and enhance durability , like adding magnets in oil filter or anodes in the cooling system, are rarely done to the less expensive vehicles, but are common on brands like Mercedes, porches, caddys, range rovers, usually do have ANODES/MAGNETS and better filters etc.
any time you use aluminum heads on an iron block (ESPECIALLY WITH COPPER HEAD GASKETS )
but any head gasket on an iron block with aluminum heads, or an aluminum intake, or aluminum, water pump,
is going to have issues over time,
your forced to use ANODES and replace those ANODES regularly as they are designed to sacrificially corrode rather than the more expensive components, and replace the anti freeze at least every 12-18 months or the result you got is very common

anodes

I got asked if USING anodes, in an engine is a good idea? electrolysis can rapidly cause damage, use of a 50% anti-freeze/50% water coolant mix and at least two good separate engine grounds to the cars frame helps but get out a multi meter and test for voltage in coolant, (more info in links)...

garage.grumpysperformance.com

magnets

heres an old post "Any source for the magnets Grumpy? what do you use? " http://www.kjmagnetics.com/proddetail.a ... SH&cat=167 magnets are ceramic and glass hard, don,t try to drill or grind them, as they can shatter or http://www.magnet4sale.com/samarium-cobalt-discs/ proper magnets trap...

garage.grumpysperformance.com

 

[NewbVetteGuy]

This coolant chart is WONDERFUL, IMHO, in understanding what coolant chemistries came from what manufacturers, in what era of time.

The obvious "safe" advice is to stick with the coolant that your car came with AND make DANG SURE you adhere to the recommended replacement intervals, especially with old Green IAT chemistries, which have super short intervals.

 

[NewbVetteGuy]

I've tried to deep-dive on coolant chemistries and I'm sure I don't have it 100% right, but I think I've got a few of the salient points right.

Composition of most (unmixed) coolants:
90% Base Fluid (Alcohols: Mono Ethylene Glycol or Mono Propylene Glycol)
Ethylene Glycol:
POISON
Sweet smell and taste
400F boiling point
8F freezing point
Better heat transfer efficiency vs. propylene glycol, but only because it's viscocity is lower; propylene glycol has a higher specific heat, so it "cools better" / removes more heat, but because it has a much higher viscocity than ethylene glycol in practical engine applications, Ethylene Glycol cools better than propelyne glycol when all things are considered. (Now think about Evans coolant which has a lower specific heat AND higher viscocity than both of them and you realize how dumb Evans coolant is if you want your engine to run COOLER).

Propylene Glycol:
Synthetic, colorless, odorless
Non-toxic
370F boiling point
-74F freezing point

I THINK, but haven't found confirmation that many coolants use a BLEND of Ethylene Glycol with some added propelyne glycol to lower the freezing point and provide more freezing resistance.

5-7% Additives:
Here's where the REAL differences happen:
There's corrosion inhibitors (the specific chemistry selected is largely what drives the differences between the different types of coolants), anti-deposit, pH buffers, defoamers, stabilizers, water wetters / "surficants", bittering agents so pets don't drink the stuff.

The Corrosion inhibitors can include:
Silicates: act as a "metal sealant" (primary anti-corrosive additive in IAT / ye olde Green coolant)
Carboxylates -oxidation will create sludge
Category of "Organic Acids"
pH buffers that help prevent the pH from dropping too low and accelerating corrosion and galvanic reactions with multiple metals in the system
Phosphates --> Phosphates + Hard water creates scale; phosphate-containing chemistries need distilled / DI / RO water

"Heavy Duty" application coolants often also include nitrites and molybdates -I have no idea what these are for, though.

The exact selected Surfacants / water wetters in coolants and the radiator additive products, seem to vary and seem to even work in narrow-ish temperature ranges. Additive products like VP Racing's "Cool Down" and Amsoil's "Dominator Coolant Boost" state that they use a blend of 3 different surficants, that target different temperature ranges, so that you get both better heat transfer when the coolant is hot (better coolint), but you also get better heat transfer when the engine is cool, which helps the engine to warm up faster.

I've also found some discussions that in very high heat racing applications that the sodium that is often a part of coolant blends will break down and fall out of suspension as a sodium salt. Quantum Blue's HP Gold markets a sodium-free formulation that doesn't break down under high heat so that extended intervals can be used even in racing apps. I have to think some other products do this, too, but I haven't found them marketed like Quantum Blue.

3-5% Unavoidable Water Molecules

Note: Again, the above percentages are for 100% coolant before water is blended in for cooling purposes.

Over time it's NOT the anti-freeze / anti-boil abilities that degrade (it's not the Ethylene Glycol or Propylene Glycol that's breaking down, it's the additive packages including the corrosion inhibitors.) Important note here: Just because your coolant still isn't boiling and your engine isn't over-heating, doesn't mean that you shouldn't replace your coolant at it's replacement interval. The pH could be dramatically changed vs. when new and you could be seeing internal corrosion / eventually WILL. (I've heard people say before "I ran my green coolant for 6 years and it still worked just fine; didn't over heat at all." -That's NOT what's going to happen...)



Coolants are generally broken down into two types:
"Type A" This is the type I'm talking about above that have ethylene glycol / propylene glycol in them to provide anti-freeze and anti-boil protection
"Type B" The "race only" coolants that are just distilled water blended with corrosion inhibitors and surfacants / "water wetters" for max cooling.



Adam

 

[NewbVetteGuy]

Named Coolant Types:

Bottom-line, up-front: Many of the coolant chemistries have issues with hard or alkaline water. Unless you want to memorize which do and don't require distilled / or DI water, then just always use the stuff, it's a no-brainer.


IAT: Inorganic Additive Technology:

• Green
• Best corrosion protection (why it's normally used with iron blocks and heads)
• Shortest Lifetime:
• 2 year / 24,000 mile change intervals
• Silicone & Phosphate
  • Phosphoric acid- removes grease and oil and softens water
  • Silicates act as metal sealant -primary anti-corrosion method
• CHEAP $$$$
• Can hurt non-metallic, plastic parts
• Cars built before the late 1990s all came with IAT (many European cars, early 1990s)

OAT: Organic Acid Tech

• Orange (Dexcool death-fluid / sludge-maker lives here)
• Purpose: A coolant that lasts way longer than traditional IATs and doesn't need replaced as often
• Negative -less corrosion protection; not compatible with other coolants.
• Designed for engines with lots of plastic and aluminum
• Extremely Long life / extended life
  • 10 years, 150,000 miles - theoretical
  • 5 years / 50,000 miles - typically recommended / practical
• EXPENSIVE $$$$
• Carboxylates for corrosion protection
• Oxidizes over time, especially if coolant levels get low; oxidation creates sludge and clogs
• Propylene Glycol base
• Cloudiness indicates OAT formulation is breaking down and losing effectiveness
• Excellent heat transfer vs. IAT
• OATs should have special hose chemistry; rubber and silicone will be degraded faster with OAT coolants
• P.S. Yes, you could argue that adding hard water to dexcool is the fault of the installer and is responsible for all the head gaskets getting "eaten", but these formulations have less corrosion protection by definition; more corrosion IS going to happen with them vs. IAT, period.
• P.P.S. Yes, you could argue that "Dexcool sludge" is also the fault of the user for blending with green fluid or not keeping the reservoir approriately topped up and allowing it to get oxidized, but it's not like you can fill that reservoir up all the way. Nothing will make me run Dexcool in anything #sorryNotSorry

HOAT: Hybrid (Inorganic / Organic Acid Technology)

• Yellow (but also purple, blue, pink, turquoise
• 5 year, 50k miles (100k theoretical)
• Some HOAT mixtures recommend changes every 2 years or 30k miles (the IAT releases life)
• OAT with more silicates to prevent corrosion (rusting and aluminum corrosion)
• G-05, G-11, G-12, Global (Euros, Japanese, some Fords)
• Purpose: Longer life vs IAT, better corrosion prevention vs. OAT "Best of Both Worlds"
• Some manufacturers recommend adding an anti-corrosive additive every 25,000 miles (because the corrosion resistance is not as good at IAT and breaks-down over time)
• "Hybrid" because it uses inorganic molecules & organic acid to fight corrosion
• DO NOT MIX HOAT and OAT -it will make sludge / goo / slushies -makes no sense, but true.
• HOAT is NOT just a blend of an IAT and an OAT, it's s special formulation

THEN we get into all the variations of HOATs, which mostly seems to be about what anti-corrosion additives they have selected.

The additive packages seem to be selected based upon whether the area it's used in has soft water or water with a higher mineral content. The EU has banned Phosphate-based chemistries because it creates scale when used with hard water which is plentiful in Europe. The regulation seems to just assume that consumers are going to top-up with tap water and it's hopeless to tell them not to. (Interestingly enough.)

Asia tends to use phosphated chemistries, because they have mostly soft water. Phosphated chemistries seem to prevent metal corrosion better, but are harder on gaskets, so it's all a trade-off and a deciding if you need a chemistry that works with hard water or not. (I'm guessing that there might be a cultural issue here too in that in Asian countries you're expected to listen to authorities, and if you can't follow instructions and use distilled / RO water, you're not going to win a lawsuit when your cooling system gets build up or corrosion, either.) Essentially, if you can trust consumers to not add hard water to their cooling system, then Phosphated chemistries seem like a better way to go.

Phosphate-free HOAT:

• Turquoise
• NAP-free; does not contain phosphates and low-silicate.
• Purpose: Be easier on engine gaskets and seals vs. phosphate-containing HOAT formulations. (less corrosion protection (for newer engines, without much iron)
• BMW, Volvo, Tesla, Mini, Audi, Jaguar, Mercedes, Porsche, Rolls-Royce, Saab, VW
• Recommended by EU MFGRs who don't need the added heat transfer abilities of phosphated HOAT; AND Europe tends to have hard water so phosphate chemistries don't work well.

Phosphated HOAT:

• Pink or Blue or Violet
• Helps inhibit corrosion more than phosphate-free HOAT
• Helps improve heat transfer more than phosphate-free HOAT
• Uses Carboxylates and phosphates, rather than silicates to inhibit corrosion
• No Silicates
• -Worse on gaskets, but better for corrosion and better heat transfer or hot climates and tiny radiators
• Japanese & Korean companies recommend
• NEVER USE with hard water (will create flaking and scale formation)
• Japanese use it because it cools better AND they tend to have soft water, which it needs.
• EU bans phosphate-free formulates because they fear people mixing hard water; some European cars still seem to use it…? -Audi 2008+ Mercedes Benz 2014+

Silicated HOAT:

• Bright purple; newest formulation; must be expensive as it's considered a luxury car / super-car coolant right now…
• Silicates and organic acids to stop corrosion
• No nitrates, phosphates
• 5 year or 150k miles with light applications
• 3 years or 300k heavy applications
• PREMIUM: Mercedes Benz, Audi, VW, Porsche, Bently, Lamborghini
• Alternative to phosphate but also may damages gaskets
• Also works well with European hard water
• Form a sand-like substance at end of life and REALLY need to be changed at recommended intervals
• I honestly can't figure out why this is BETTER than the other HOAT formulations and why manufacturers would bother to release it as it doesn't seem like some magical formulation that stops all corrosion, lasts forever, and cools amazingly, even with hard water.

Adam

 

[NewbVetteGuy]

Issue this "deep dive" brought up for me:
1. There are big issues that come up when blending from different types of coolants that can cause sludge / gels to form. This seems to come primarily from incompatibilities between the anti-corrosion additives. That must mean that there are potentially certain anti-corrosion additives in the coolant additives bottles that might create sludge / gels if used with an incompatible coolant... How the @W$#@ do we figure out what's in the additive bottles? I have no idea...

I also want to stress something Grumpy has said in almost every cooling thread, and that's that WATER is the best coolant, if you're looking for lower temperatures, BUT with a higher % of water in your blend, you need EXTRA anti-corrosive additives to make up for that extra water.

The added water cools in at LEAST two different ways:
1. The higher specific heat of the blend with water (literally the coolant carries more heat away with it). This will give you more heat moved to the radiator with less of a temp rise at your sensor.

The specific heat of 100% pure water @ 80C / 176F is 1.0026; at 90C / 194F it's 1.0049
The specific heat of a 50/50 water ethylene glycol blend @ 80C/176F is .87343; at 90C/194F it's .88075
The specific heat of a 25% glycol-water blend @ 80C/176F is .95393; at 90C/194F its .95851

2. Water has a much lower dynamic viscocity than a 50/50 glycol blend

Water dynamic viscocity @ 180F: .345 centiPoise
50% glycol dynamic viscocity @ 180f: .825 centiPoise
25% glycol dynamic viscocity @ 180F: .565 centiPoise


-Ultimately when you use a 50% Ethylene Glycol blend you need to increase the coolant flow to make up for the decreased thermal conductivity by the numbers below BUT that's made even harder by the fact that the glycol-water blends are more viscous and resist that flow. A GOOD HIGH FLOW WATER PUMP IS YOUR FRIEND!

At 40F you require +22% more flow of a 50/50 blend to equal the cooling power of pure water.
At 180F you require +14% more flow of a 50/50 blend to equal the cooling power of pure water.

(If I did the math right, moving from a 50/50 blend to a 75% water / 25% glycol blend, should net you a 7% improvement in liquid-side cooling from the combination of improved thermal conductivity and increased flow from the reduced viscocity.)

(Maybe those underdriven crank and water pump pulleys aren't such a good idea in those C3 Corvettes that like to overheat if you look at them funny..?)


Adam

 

[NewbVetteGuy]

Increasing the % of water in your coolant blend is a highly effective way to increase your systems cooling ability. It increases the thermal conductivity of the fluid / system AND increases coolant flow through decreased dynamic viscocity at the same time.

If you take this approach, you need to:
1. Increase the amount of anti-corrosion additive that you add to make up for the water (VP Racing gives recommendations on using their "Cool Down" product to do this, Amsoil probably has similar guidance for their Dominator Coolant Boost product) -these products don't last forever, so follow the top-up and replacement recommendations of the MFGR.
2. Determine how much freeze / slush protection and boil-over protection your engine needs.


The table below will give you "Freeze" / "Burst" (pop-out freeze plugs) temps for a given blend of propelyne glycol-based coolant. The "freeze" temp is the temp at which the coolant will turn to a shushie-like consistency and be hard/ impossible to pump through the water pump.

For the boiling point, you will need to also consider the pressure of your radiator cap as increased system pressure will increase the boiling point.

The simple calculation is that every +1 PSI of pressure the boiling point rises 3 degrees Fahrenheit.

Note: A high volume water pump will likely ALSO increase the pressure in the system as the coolant flow encounters flow bottlenecks in critical areas like the heads' coolant passages this is a GOOD thing as it helps resist localized boiling / steam. High volume water pumps are the gift that keeps on giving to your cooling system.




Example: My car is garaged in a garage attached to my house and I live in the relatively temperate Seattle. The coldest my garage has EVER gotten was 39F last winter.

I feel comfortable running a 75% water / 25% Ethylene Glycol blend, but someone who lives in a more extreme climate might want the added cold weather protection of a 70/30 or 66/33 blend.


My 75/25 blend gives me "Freeze" / Slush protection to 18F and "Burst Protection" down to 10F. -Way lower than I should ever expect to get even if the power goes out for several DAYS in Seattle winter.
Note: Yes, my numbers are more conservative than the table I pasted above. The link below includes a calculator for specific Propylene Glycol products made from Dow chemicals and provides more conservative estimates for slush and freeze points, so I prefer to use these numbers as they seem closer to a "worst case". https://goglycolpros.com/pages/glyc...point-burst-point-protection#glycolcalculator


On the boiling side, if I had no radiator cap, a 75/25 blend would boil at 218F, but I have a 16 PSI radiator cap, which adds another 48 degrees F of boil protection, -for 266F. I think it's important to have plenty of additional boil-over capacity because the hottest spots in your heads are going to see much hotter temps potentially than even the temp sensor in my heads. The good news is that heads' coolant jackets tend to be the smallest area and the highest pressure areas of an SBC cooling system.


When it comes to practicalities of how did I select my coolant and additives to stay "compatible" and not form sludge, I just stuck with one company's products and asked them about how much additional anti-corrosion additive to add to make up for the added water in the blend.

Definitely not the cheapest option but I went with VP Racing's "Stay Frosty High Performance", which is a Type A coolant and VP Racing "Cool Down" additive. You could also blend VP Racing "Stay Frosty High Performance" (Type A) with VP Racing "Stay Frosty Racing" which is a Type B coolant that's just distilled water essentially already blended with the right amount of the "Cool Down" anti-corrosion and surfactants/ "Water wetters".




The case for a lot of people to run with a higher % of water in their coolant blend to get better cooling performance just seems so strong to me, I'm surprised I don't see it talked about more often.


Before Grumpy asks, YES, I added a big Zinc anode to my radiator system drain, just in case I forget to add more anti-corrosion additive or change the fluid quite on time...

I added it because so many guys here recommend it and install them in their cooling systems.


Adam

 

[Indycars]

Thanks, lots of good info there !