Interesting read on coolants

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Originally Posted By: Donald
No date on the writeup. Maybe old info? Certainly Dexcool has had its problems, but its not as straight forward as the writer suggests. In a vehicle designed for Dexcool its the right coolant. In fact its probably best to keep the type of coolant that came with your car to begin with. Worst is the AMAM stuff (Dexclone) at Walmart. Not saying to use only coolant from the dealer. Thee are many types of coolant available from Zerex. If you have an old vehicle, you would be safe moving up to Peak Global or G-05 (with a water flush).


Interestingly, I am the guy that wrote up that post. I need to mention here that the problems with Dexcool are noted not only by myself but by GM mechanics who have had current issues with GM Dexcool based products. GM does not use proprietary alloys that chemically are vastly different than the rest of the world. Coolants are spec'd. by engine manufacturers and in the case of GM serious mistakes were made. Reformulation has helped some but still does not totally correct the problems. Inherently the G-05 standard and the Cat ELC-1 standards are superior to Dexcool and both of these are used worldwide according to the Zerex reps I talked to.
 
Originally Posted By: Donald
You don't need flush chemicals. Flush it with water a few times. Of course a last flush with distilled water is best, but if you can drain the block and radiator, there is only a little plain water left in the heater core. I would then go with Peak Global or Zerex G-05. Not familiar with Beck/Arnley but they typically make quality products. Some Walmarts carry Peak Global.


Flush chemicals are acidic instead of basic. Flush chemicals will remove traces of the old reacted corrosion inhibitors as well as helping to clean metal surfaces of metal oxides leaving the metal surfaces clean for the new coolant to react faster with the metal surfaces thereby enhancing speed of protection from corrosion. Only in cases where the owner is sticking with the same coolant type is a chemical flush not needed. In that case flush with distilled water. If you know your coolant system capacity, calculating how much coolant concentrate is a trivial back of the envelop calculation.
 
Thanks Falcon for the repost. However I do not have the time to come in and monitor this thread as well. Too many times coolants can be a challenge as with other chemicals and lubricants in vehicles. For me as a chemist and material scientist, the first question I ask is what is the exact chemical composition. Then I ask what is the surfaces that chemical composition is going to come in contact with. No engine manufacturer has a corner on specific engine technology that excludes exclusively one chemical over another. However certain technologies actually rise to the top as best of the bunch. In this case for coolants the Caterpillar ELC-1 specification is one of the best out there. For more info check the following post.

http://www.bobistheoilguy.com/forums/ubb...amp;type=thread

Stalag
 
Why are you so critical of Dexcool and praise Cat ELC-1 which for all intents and purposes is 2-EHA containing Dexcool?

You being a chemist you should no better than that. Dexcool like any coolant was extensively tested on metals contained in cooling systems and performed very effectively for a very long service life. This is why it the most common HD coolant also.

A lot of people have pointed out that Dexcool requires the system to be full and free from air, best accomplished by using a pressurized reservior or degas bottle. The problems Dexcool had were not a chemistry problem per se, but mostly a poor gasket problem allowing the system to run low. That's the general nature of long life OAT coolants vs IAT, as OATs work best when the system is full.

Dexcool does not cause problems in all vehicles it was filled with even from the beginning back in 1995. And it doesn't cause problems on later models factory filled with it. All coolants have some shortcomings. For instance, the borates and nitrites in G-05 can attack aluminum when the other inhibitors become depleted, silicates may reduce water pump seal life etc. You know, Ford is going to Dexcool now and formulas similar to Dexcool are used in Europe. I think it's bad advice to say everyone should dump their Dexcool.
 
It's just so yesterday. Nothing wrong with Dex.

And just a note. Our service vans have heat exchangers plumbed into the coolant bypass yielding almost 3 times stock volume. This virtually guarantees air in the system. No problems whatsoever.
 
I think it's cute that he mentions his Ph'D. Never seen an apostrophe in the title before.
 
Originally Posted By: mechanicx
Why are you so critical of Dexcool and praise Cat ELC-1 which for all intents and purposes is 2-EHA containing Dexcool?

You being a chemist you should no better than that. Dexcool like any coolant was extensively tested on metals contained in cooling systems and performed very effectively for a very long service life. This is why it the most common HD coolant also.

A lot of people have pointed out that Dexcool requires the system to be full and free from air, best accomplished by using a pressurized reservior or degas bottle. The problems Dexcool had were not a chemistry problem per se, but mostly a poor gasket problem allowing the system to run low. That's the general nature of long life OAT coolants vs IAT, as OATs work best when the system is full.

Dexcool does not cause problems in all vehicles it was filled with even from the beginning back in 1995. And it doesn't cause problems on later models factory filled with it. All coolants have some shortcomings. For instance, the borates and nitrites in G-05 can attack aluminum when the other inhibitors become depleted, silicates may reduce water pump seal life etc. You know, Ford is going to Dexcool now and formulas similar to Dexcool are used in Europe. I think it's bad advice to say everyone should dump their Dexcool.


I have a distinct problem with the formulation of the base dexcool itself. Some of the problems of straight Dexcool are fixed with the nitrated/nitrited formulations. In 2008 when I first researched this issue, too many current posts were coming up with the sludging issue for their vehicles that contained dexcool. This was verified when I talked to Ford mechanics about this. It seems that Ford attempted to use straight Dexcool in one of their model lines. So many coolant related issues came up they dropped it and went to the G-05 coolants.

I have seen better results with the nitrated/nitrited versions of organic acid technology coolants. This is verified by the few to no issues with either the G-05 or the ELC-1 coolant. Also Caterpillar posts full information directly on their own formulation and on the testing required for certification as ELC-1 (this you must dig for since it is not easy to find). If either Prestone or Peak did this I would have far more comfort in recommendations of their formulations including any reformulated coolants they have. To date no coolant manufacturer/formulator has ever posted full technical data except for Caterpillar. However I made the exception for Zerex products because their coolant line is clearly labeled and if you buy the right coolant you will match easily what is already in your radiator from the automobile manufacturer.

That said no pressurized system is hermetically sealed and at STP a coolant system when cold does see air in the cooling system voids. There is no way to get around this unless you fully seal the system. Pull a hard vacuum on the system (this would be less than 10 torr with 760 torr being defined as 1 atmosphere). Refill the system with Nitrogen and/or Argon. And this must be repeated no less than 3 times.

No coolant left beyond the life of the anticorrosive chemicals in solution will protect the engine. This fact is irrespective of who makes the coolant. Also it is a fact that almost all mechanics and DIY'ers will not use distilled water when distilled water is recommended by both the coolant manufacturers and the automobile manufacturers. The old silicate/phosphate formulation was tolerant of tap water but with Dexcool, ELC-1, G-05, or any other specialty coolant out in use today are all without exception not tap water tolerant.

The major reason silicate/phosphate coolant is not being recommended anymore was enunciated by the Caterpillar representative I spoke with. "The new coolant (ELC-1) has longer lasting protection and is not abrasive like the older coolant (silicate/phosphate base coolants). As a result as long as our coolant change procedures are followed to the letter, we have never seen a coolant related failure ever in relation to a cooling system converted to the new ELC-1 coolant." This statement was made in 2008 following the release of the coolant in 1995 thirteen years before.
 
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Originally Posted By: stalag
Also Caterpillar posts full information directly on their own formulation and on the testing required for certification as ELC-1 (this you must dig for since it is not easy to find).


Any links or even better patent numbers you can give. I don't mind searching myself but if someone else has already done the work, why bother?
 
OK but I just don't agree that nitrites or molybdates are necessary to make Dexcool work. The nitirites are used in HDs for diesel wet liner cavitation-erosion protection. Adding nitirites, molybdates, phopshate and other IAT gives you a HOAT, and some of the advantages of IAT inhibitors but OAT coolants like Dexcool do work and for a longer service life.

My point with the nitrite and borate thing is that some manufactures do not recommend borate and nitirites because it is counter productive for maximum aluminum protection. The Japanese formulas did away with borates for example.

I'm not sure why you say Dexcool and G05 is not tolerant of tap water as persumably original green? I would consider Dexcool very tolerant of tap water. You are a chemist, you should know under ASTM standards coolants are also tested for performance while using tap water.

It's not necessary for Dexcool to be totally absent of air, only for the system to not be ran with low coolant level in the engine for any extended periods of time. All that is need is a pressurized overflow bottle, and as I said, since 1995 and counting those systems have not evidenced sludging using Dexcool. Those systems are self bleeding of air basically.

Dexcool will even work in system without the high mounted pressurized reservoir/degas bottle, as a lot of people are doing it successfully. I just don't recommended it because if there is a coolant leak and lack of maintaining the coolant level, yes dexcool can be more prone to sludge in these systems.

All Dexcool formulas are similar containing 2EHA but not identical. Chevron's Havolime seems to be more sludge resistant than some universal types, Zerex's Dexcool I believe contains molybdate, and as you mentioned HD coolants often contian nitrite. But it comes back to the high mounted surge tank/reservoirs. With those you can run any brand of Dexcool and they basically never sludge.
 
Originally Posted By: stalag
Originally Posted By: mechanicx
Why are you so critical of Dexcool and praise Cat ELC-1 which for all intents and purposes is 2-EHA containing Dexcool?

You being a chemist you should no better than that. Dexcool like any coolant was extensively tested on metals contained in cooling systems and performed very effectively for a very long service life. This is why it the most common HD coolant also.

A lot of people have pointed out that Dexcool requires the system to be full and free from air, best accomplished by using a pressurized reservior or degas bottle. The problems Dexcool had were not a chemistry problem per se, but mostly a poor gasket problem allowing the system to run low. That's the general nature of long life OAT coolants vs IAT, as OATs work best when the system is full.

Dexcool does not cause problems in all vehicles it was filled with even from the beginning back in 1995. And it doesn't cause problems on later models factory filled with it. All coolants have some shortcomings. For instance, the borates and nitrites in G-05 can attack aluminum when the other inhibitors become depleted, silicates may reduce water pump seal life etc. You know, Ford is going to Dexcool now and formulas similar to Dexcool are used in Europe. I think it's bad advice to say everyone should dump their Dexcool.


I have a distinct problem with the formulation of the base dexcool itself. Some of the problems of straight Dexcool are fixed with the nitrated/nitrited formulations. In 2008 when I first researched this issue, too many current posts were coming up with the sludging issue for their vehicles that contained dexcool. This was verified when I talked to Ford mechanics about this. It seems that Ford attempted to use straight Dexcool in one of their model lines. So many coolant related issues came up they dropped it and went to the G-05 coolants.

I have seen better results with the nitrated/nitrited versions of organic acid technology coolants. This is verified by the few to no issues with either the G-05 or the ELC-1 coolant. Also Caterpillar posts full information directly on their own formulation and on the testing required for certification as ELC-1 (this you must dig for since it is not easy to find). If either Prestone or Peak did this I would have far more comfort in recommendations of their formulations including any reformulated coolants they have. To date no coolant manufacturer/formulator has ever posted full technical data except for Caterpillar. However I made the exception for Zerex products because their coolant line is clearly labeled and if you buy the right coolant you will match easily what is already in your radiator from the automobile manufacturer.

That said no pressurized system is hermetically sealed and at STP a coolant system when cold does see air in the cooling system voids. There is no way to get around this unless you fully seal the system. Pull a hard vacuum on the system (this would be less than 10 torr with 760 torr being defined as 1 atmosphere). Refill the system with Nitrogen and/or Argon. And this must be repeated no less than 3 times.

No coolant left beyond the life of the anticorrosive chemicals in solution will protect the engine. This fact is irrespective of who makes the coolant. Also it is a fact that almost all mechanics and DIY'ers will not use distilled water when distilled water is recommended by both the coolant manufacturers and the automobile manufacturers. The old silicate/phosphate formulation was tolerant of tap water but with Dexcool, ELC-1, G-05, or any other specialty coolant out in use today are all without exception not tap water tolerant.

The major reason silicate/phosphate coolant is not being recommended anymore was enunciated by the Caterpillar representative I spoke with. "The new coolant (ELC-1) has longer lasting protection and is not abrasive like the older coolant (silicate/phosphate base coolants). As a result as long as our coolant change procedures are followed to the letter, we have never seen a coolant related failure ever in relation to a cooling system converted to the new ELC-1 coolant." This statement was made in 2008 following the release of the coolant in 1995 thirteen years before.


I'll post this on this forum as well since you seem to be discussing in both places(Crown Vic Forum):
How do you know Cat ELC is not a Dexcool variant but a G-O5 variant? It would appear based on the following information that Cat ELC, made Texaco is/was originally called Dexcool Hd - Nitrited Dexcool.

http://www.penray.com/images/01.010.pdf

Based on the following links from Penray it would appear there are only four inhibitor packages used here in the US

Inhibitor package 2798-Dexcool:
http://www.penray.com/images/2798_InhibitorSheet_3.pdf

Inhibitor package 2798N - nitrited Dexcool package that is CatELC and compatible with Cat ELC:
http://www.penray.com/images/01.010.pdf

Penray Flyer stating that 2798N is Cat ELC:
http://www.penray.com/images/98.002.pdf

Penray 2705 Inhibitor package - Hybrid Ford/Chrysler:
http://www.penray.com/images/INH2705Flyer.1206.pdf

Penray 2792 Inhibitor Package - Fully formulated Convetional:
http://www.penray.com/managex/index.asp?x=313&y=314&articlesource=314&navID=

All Inhibitors: http://www.penray.com/managex/index.asp?x=313&y=313&articlesource=313&navID=

I don't think its a big deal if its(Cat ELC) Dexcool or not based on your statement that if it is nitrited it will mitigate any compatibility issues. I certainly defer to chemical expertise.


Edit: Cat MSDS list Texaco as Manufacuter - https://www2.itap.purdue.edu/msds/docs/12003.pdf
 
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Originally Posted By: mechanicx
OK but I just don't agree that nitrites or molybdates are necessary to make Dexcool work. The nitirites are used in HDs for diesel wet liner cavitation-erosion protection. Adding nitirites, molybdates, phopshate and other IAT gives you a HOAT, and some of the advantages of IAT inhibitors but OAT coolants like Dexcool do work and for a longer service life.

My point with the nitrite and borate thing is that some manufactures do not recommend borate and nitirites because it is counter productive for maximum aluminum protection. The Japanese formulas did away with borates for example.

I'm not sure why you say Dexcool and G05 is not tolerant of tap water as persumably original green? I would consider Dexcool very tolerant of tap water. You are a chemist, you should know under ASTM standards coolants are also tested for performance while using tap water.

It's not necessary for Dexcool to be totally absent of air, only for the system to not be ran with low coolant level in the engine for any extended periods of time. All that is need is a pressurized overflow bottle, and as I said, since 1995 and counting those systems have not evidenced sludging using Dexcool. Those systems are self bleeding of air basically.

Dexcool will even work in system without the high mounted pressurized reservoir/degas bottle, as a lot of people are doing it successfully. I just don't recommended it because if there is a coolant leak and lack of maintaining the coolant level, yes dexcool can be more prone to sludge in these systems.

All Dexcool formulas are similar containing 2EHA but not identical. Chevron's Havolime seems to be more sludge resistant than some universal types, Zerex's Dexcool I believe contains molybdate, and as you mentioned HD coolants often contian nitrite. But it comes back to the high mounted surge tank/reservoirs. With those you can run any brand of Dexcool and they basically never sludge.




In answer to a question in one of the above posts.
Full patent searches can be made by contacting the people at the following address. For a fee they will pull all patents for you on the subject.

Chemical Abstracts Service Science IP section.

http://www.scienceip.org/

I personally will not post these patents as my job would be on the line due to the work I do.

Testing of coolants I have never done personally. I have never seen tests of coolants that follow the Caterpillar ELC-1 testing specifications other than select ELC-1 coolants.

Nitrites/nitrates are inhibitors of the esterification reaction. As such they are needed not only for cavitation purposes but also for inhibition of esterification. I suspect because of the nature of borates and molybdates knowing the chemical structures they also act in part as esterification inhibitors.

Even though ASTM requires testing using tap water, many municipalities have wildly different loads of total dissolved solids. Also free chloride in the system especially from chlorination of municipal water supplies adds another contaminant that bypasses the anticorrosive chemicals and eats directly at the active metals in the system. This information I have personally seen when I worked at a state EPA lab years ago. For me there is a huge amount of chemstry I just do not want to get into over this as far as an arguement (debate). I have neither the lab space or time or money to pursue the direct testing of chemical systems in coolants. Suffice to say some of the ASTM methods of testing were never updated and never account for variations in tap water from municipal supplies to softened water to straight untreated water from wells and streams that in certain cases can have very significant salt loads in the water. Caterpillar does spell out in their documentation on engine fluids an upper bound to which water would be of sufficient quality. However in the same documentation distilled water is recommended in all cases. The Caterpillar documentation is easily available on their website. Go read it.
 
Originally Posted By: 3311
I'll post this on this forum as well since you seem to be discussing in both places(Crown Vic Forum):
How do you know Cat ELC is not a Dexcool variant but a G-O5 variant? It would appear based on the following information that Cat ELC, made Texaco is/was originally called Dexcool Hd - Nitrited Dexcool.

http://www.penray.com/images/01.010.pdf

Based on the following links from Penray it would appear there are only four inhibitor packages used here in the US

Inhibitor package 2798-Dexcool:
http://www.penray.com/images/2798_InhibitorSheet_3.pdf

Inhibitor package 2798N - nitrited Dexcool package that is CatELC and compatible with Cat ELC:
http://www.penray.com/images/01.010.pdf

Penray Flyer stating that 2798N is Cat ELC:
http://www.penray.com/images/98.002.pdf

Penray 2705 Inhibitor package - Hybrid Ford/Chrysler:
http://www.penray.com/images/INH2705Flyer.1206.pdf

Penray 2792 Inhibitor Package - Fully formulated Convetional:
http://www.penray.com/managex/index.asp?x=313&y=314&articlesource=314&navID=

All Inhibitors: http://www.penray.com/managex/index.asp?x=313&y=313&articlesource=313&navID=

I don't think its a big deal if its(Cat ELC) Dexcool or not based on your statement that if it is nitrited it will mitigate any compatibility issues. I certainly defer to chemical expertise.


Edit: Cat MSDS list Texaco as Manufacuter - https://www2.itap.purdue.edu/msds/docs/12003.pdf

Excellent information in this post. You will also find good information in the archived set of posts a few posts above this one that I give.
 
Information on Penray looks to me that this company is an original additive supplier for coolants much like Lubrizol is for lubricants. Chances are Penray technology shows up in many coolants much like Lubrizol technology shows up in many lubricants.
 
Originally Posted By: stalag
In answer to a question in one of the above posts.
Full patent searches can be made by contacting the people at the following address. For a fee they will pull all patents for you on the subject.

Chemical Abstracts Service Science IP section.

http://www.scienceip.org/

I personally will not post these patents as my job would be on the line due to the work I do.

I'm simply asking for the patent number for the coolant which you recommend and are referring to as ELC-1 and which I know as Caterpillar Extended Life Coolant meeting spec EC-1. I can do a look up by myself given what I request. I don't think posting the number here will get you in trouble.
 
Lets agree to disagree. Some like Dexcool, some don't. GM is sticking with Dexcool and that does say something. I am sure they have a small army of chemists and engineers that have gone all through this. Some may even have doctorates!
 
Well of course distilled water is better than unknown water. Anyway I'm not questioning your knowledge of chemisty or trying to get in a debate about coolant chemisty and a tit for tat. I'm just pointing out that not all manufactures want nitrites or borates (or silicates and phosphates for that matter) and all inhibitors have their shortcomings. OAT coolant like Dexcool can work fine without nitrites. I believe nitriting is more of a diesel cavitation matter than a chemisty matter.

Earlier on GM did have some problems with Dexcool in some applications. But don't think Dexcool wasn't tested extensively by Texaco, GM, and Ford probably more than CAT. Cat adopted Dexcool and again nitriting or molybdating HD coolants for cavitation protection was common way before Dexcool an OATs.

Is your issue with Dexcool the 2EHA or that it is an OAT formula? Have you heard of Peak Global? It is an OAT coolant that as far as anyone knows uses only benzoate as its inhibitor. Also some HD coolants like Peak Final Charge use OATS and no nitrites or molybdates.
 
Originally Posted By: mechanicx
If anything I think Japanese makes with their proprietary coolant and ATF violate the spirit of the MM Act.


Agreed. I find it odd that there are so many posters complaining about dexos1, yet don't extend those complaints, at least not as much, to DexCool and Dexron, let alone G-05, G-11, Genuine Nissan/Infiniti Antifreeze, Matic J, Matic S, and so forth.

Whether or not DexCool is or isn't a good coolant (personally, I think it's fine, but that's not relevant), from a pure marketing and customer convenience side, it's a great success. One can buy it anywhere, one can buy it at a decent price, and one can choose from one of several brands. They're clearly labelled, and GM clearly calls for DexCool. It couldn't get much simpler.
 
Originally Posted By: Donald
Lets agree to disagree. Some like Dexcool, some don't. GM is sticking with Dexcool and that does say something. I am sure they have a small army of chemists and engineers that have gone all through this. Some may even have doctorates!


Yes exactly, and also Ford has tested and adopted Dexcool. It has worked flawlessly in millions of vehicles for over 17 years. That's what counts the most. I'm not going to convince stalag of anything. He'll beat me down with chemistry technical terms.
 
I found the original texaco patent on which the caterpillar ELC-1 coolant is based. The exact chemical composition is listed in example 1 and example 11. The patent number is 4587028 and has a patent date of May 6th, 1986.
 
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