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Why Coolant Additives
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by Steve Jack
Concept One Pulleys
Jackstands at Old Cars Only

Okay...here's my speeeeal on these and why I use them. I think you will change your mind about some of these after doing some simple research. I used to be a little skeptical about some of this. However, after doing much research in the cooling and coolant areas my mind was changed a couple of years ago. Now I am NOT saying that this stuff is going to make an appreciable difference on your temperature gauge per se and the benifits of these products are hard to put a yardstick to since we don't directly see the evidence. But, a chemist from Prestone taught me most of this and how these additives work. I am a believer now. Your decision is yours!

Actually even tho these products are marketed toward problematic areas in general, the additives are in fact worth using under normal circumstances too... AND most of the newer coolants are employing much the same additives I might say, according to Prestone engineers. Both EG and PG coolants have some sort of surfactant additive added and in most cases are the identical chemical concoction found in these additives! So they see the worth too and obviously antifreeze 10 years ago was pretty mundane compared to today's complicated products. So, these additives have played an improvement role, especially with advent of aluminum parts etal and smaller radiators.

Also, take into account that many of US are not running the "perfect mix" of 50/50 mix per se, something that the coolant industry designs its products for specifically, therefore the surfactants and additives that is in the original product is diluted to an extent depending on mixture, so a surfactant/additive is quite appropriate in any in most cases and even with a 50/50 mix as well I would argue.

My research shows that these products provide excellent protection from cavitation erosion in the water pump and cylinder head. Localized boiling in the cylinder head forms vapor bubbles which collapse when they come in contact with cooler liquids. This collapse creates tremendous shock waves which removes the inhibitor film from the aluminum surface and can cause catastrophic erosion of the aluminum if the inhibitor does not reform the film quickly. Another problem created by cavitation erosion is the deposition of the removed aluminum as a salt with poor heat transfer properties in the lower temperature radiator tubes. These products prevents this corrosion through effective film formation and smaller vapor bubble formation, which has a less violent collapse. Foam control is equally important since entrained air will cause cavitation erosion due to the collapse of foam bubbles. These products provide excellent control of foam with water alone and glycol solutions due to their "surfactant actions".

Now understanding the chemistry and its worth, I run these for several reasons really. First, surfactants help alot with getting air out of the system completely. Second, I run high flowing pumps in all my engines with "overdrive" technology. This means at 6500rpms indicated on the Camaros tach, means the water pump is turning at a whopping 7600+rpms and keep in mind it's a high flow pump! I do not want to induce cavitation and air in places I do not want it, therefore the "surfactant action" of the additives will help alleviate this air problem. I have seen this with my own two eyes in test tanks. The secondary feature of inhanced heat transfer does not help me per se, because I am like you guys (Ed and Deuce) and design systems that are adequate, but if I ever lose pressure or coolant the edge might get me to a safe haven just in case. Third, there are corrosion inhibitors abound in these additives and with less than a 50/50 mix, with all the aluminum parts that my cars engines have (water pumps, heads, intakes, radiators) this is further insurance against electrolysis and corrosion by keeping the coolant at the correct PH levels.

The benefits of WaterWetter or Purple Ice are:

-Doubles the wetting ability of water
-Improves heat transfer
-Has the ability to reduces cylinder head temperatures
-Reduces rust, corrosion and electrolysis of all metals
-Provides long term corrosion protection
-Cleans and lubricates water pump seals (new waterpumps do not need seal lubrication tho....)
-Prevents foaming
-Reduces cavitation and the corrosion that goes with
-reacts with hard water to reduce scale

Also, some cooling systems are on the ragged edge regardless of design due to footprint design or area limitations etc. I get over 100 emails a month on either cooling or electrical issues from various articles. I cannot tell you how many times some rodder has stuck a beheamoth 502/502 in a 67 NOVA and can't get it to cool in Texas. He may have the largest/most efficient radiator he can get in there too. His sytem is usually on the edge of cooling. By adding a high flow pump, a higher CFM fan and some water wetter he has made a huge difference in heat transfer and is happy as a lark. The additive helps build a cushion due to its ability to move heat faster.

So, you can do what you want, but in my experience and after learning all it's attributes, it's a no brainer and cheap too. I hope I can change some of those "rodding" minds. That's my story and I'm stick'in to it ;)

Acidity and alkalinity is measured on a "pH" scale, where 7 is neutral, lower numbers represent increasing acidity and higher numbers increasing alkalinity (pH is chemist talk for the concentration of hydrogen ions in solution). Pure water is neutral with a pH of 7. Battery acid reads 2 or 3 on the pH scale, while baking soda might rate a 10 or 11.

Whether the coolant is acidic or alkaline makes a big difference. As long as it remains alkaline, corrosion is inhibited. But if it goes acidic, corrosion starts to eat away at the interior of the system. The corrosion-inhibiting additives in antifreeze are put there to keep the solution on the high side of the pH scale. The alkalinity of a typical antifreeze/water mixture will vary depending on the additives used and ratio of ingredients, but is usually somewhere between 8 and 11. The average for most antifreezes is around 10.5, but when diluted 50/50 with water and added to the cooling system the pH drops to the 8.5 to 9 range. Higher is not necessarily better, though, because some of the new long-life coolants have a pH of only 8.3. Staying power is what counts.

This point speaks to my diatribe above about corrosion inhibitors.....To ensure that the coolant remains alkaline for a reasonable length of time, there must be enough corrosion inhibitor to neutralize the acids formed from glycol degradation that occur over time. This neutralizing capability is called "reserve alkalinity," and it varies depending on the type and quantity of additives used in a particular brand of antifreeze.

Heat, dissolved oxygen, minerals in the water and corrosion inhibitor reactions at the metal surface gradually "use up" the corrosion inhibitors; once depleted, the coolant becomes acidic and corrosion accelerates. The trick to preventing internal corrosion, therefore, is to change the coolant before all the reserve alkalinity has been used up.

Test strips are commonly available from your favorite parts store. Just do it to protect your aluminum parts.

Steve Jack
Concept One Pulleys
Jackstands at Old Cars Only

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