Correlation between 2-Ethylhexanoic acid and Solder corrosion

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FCD

FCD

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I've posted this in a couple threads already but i thought it deserved its own.

I've been investigating why is it that OAT coolants have been accused of being bad for solder, copper, brass radiators.

This book : "Engine Coolant Testing ( 1993 )" states this :

"The effects of 2-Ethylhexanoic acid was clearly seen in coolants, M,N and O where there was no diacid present, the high lead solder weight loos increased from 79 to 378mg as the 2-Eha acid level increased from 0.5 to 3.5%"

https://books.google.es/books?id=kS...ing%20solder%20ethylhexanoic&f=false

So which coolant do have it or not? from what i've been able to gather Dexcool and Dexclones do have it, other OAT coolants such as VW's G12, G12+, G12++ or G13 or the Asian P-OAT coolants don't ( i wish i could find the source where i read that right now )

I would say this is quite plausible as Dexcool is infamous for causing all kinds of problems whereas the others are not.
 
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I work at a radiator shop. We see the damage Dex does to soldered radiator and heaters. Every customer with a soldered radiator gets the talk. I have also noticed that if spilled on my floor Dex is impossible to mop up! That spot will stay wet and slippery for 2 days no matter how much i mop it.

I do not know the chemistry as to why dex eats solder. I just know that it does and very quickly. It has destroyed a brand new recore in a few months.
 
Originally Posted by FordCapriDriver
It seems 2-Ehtylehxanoic acid has a lot to do with that, and as i said apparenly Dexcool is just about the only coolant still using that chemical.




Prestone all makes all models was using it. I do not know if they have changed anything in it.
 
I was surprised to find that Ford used a Dexclone (Ford Orange) in my 2014 Focus and 2016 Escape. I think they are getting away from it with their latest coolant but I don't know if they will use the new stuff in all models. I may use a P-HOAT or PGL when it comes time to change out the OE coolant. Is it possible that some of these new radiators don't use solder so Ford didn't see an issue with 2-EHA?
 
Originally Posted by FordCapriDriver
It seems 2-Ehtylehxanoic acid has a lot to do with that, and as i said apparenly Dexcool is just about the only coolant still using that chemical.


That's not true, at least around here. I went and looked at all of the antifreeze jugs, and most of them (especially the quart jugs) showed they still have 2-EHA in them. I know for sure that the Valvoline Zerex silver bottles for Asian brands say they are 2-EHA free.
 
Peak had several that used 2-EHA. Long Life and Extended Life definitely had it, along with Prestone AMAM yellow. If you're on the fence about using a long life coolant, Zerex Green is rated for 5 years 150K, and many people have used G-05/Premium Gold with good results. I've even read that Ford is considering dumping Specialty Orange (2-EHA containing) in favor of something else. The Asian P-HOATs are also really good, but I've never used them in a system containing solder. The only vehicle I have with a brass radiator is the F-450, and it's doing just fine on regular green, DCA-2 SCAs, and a coolant filter.
 
Originally Posted by Chris142
Originally Posted by FordCapriDriver
It seems 2-Ehtylehxanoic acid has a lot to do with that, and as i said apparenly Dexcool is just about the only coolant still using that chemical.




Prestone all makes all models was using it. I do not know if they have changed anything in it.


Well yeah, most of the all makes all models coolants are Dexclones so...
 
Originally Posted by bullwinkle
Peak had several that used 2-EHA. Long Life and Extended Life definitely had it, along with Prestone AMAM yellow. If you're on the fence about using a long life coolant, Zerex Green is rated for 5 years 150K, and many people have used G-05/Premium Gold with good results. I've even read that Ford is considering dumping Specialty Orange (2-EHA containing) in favor of something else. The Asian P-HOATs are also really good, but I've never used them in a system containing solder. The only vehicle I have with a brass radiator is the F-450, and it's doing just fine on regular green, DCA-2 SCAs, and a coolant filter.


I've already settled on a VW G12++ / G40, Silicated OAT for both my cars, no 2-Eha and it seems to be doing just fine.

Until a few months ago i was using conventional green in both, then the Capri overheated on me one day and when i drained the cooling system i found the radiator was severely clogged with what seemed like Silicate gel / dropout.

My intention was to make a PSA out of this thread warning people not to use 2-Eha containing coolant in cooling systems containing Lead Solder.
 
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So does anybody know if late model cars (Fords in my case) still use solder in their radiators?
I can't see Ford going over to 2-EHA coolant knowing it can cause these problems in soldered radiators...
 
Originally Posted by FordCapriDriver
Originally Posted by bullwinkle
Peak had several that used 2-EHA. Long Life and Extended Life definitely had it, along with Prestone AMAM yellow. If you're on the fence about using a long life coolant, Zerex Green is rated for 5 years 150K, and many people have used G-05/Premium Gold with good results. I've even read that Ford is considering dumping Specialty Orange (2-EHA containing) in favor of something else. The Asian P-HOATs are also really good, but I've never used them in a system containing solder. The only vehicle I have with a brass radiator is the F-450, and it's doing just fine on regular green, DCA-2 SCAs, and a coolant filter.


I've already settled on a VW G12++ / G40, Silicated OAT for both my cars, no 2-Eha and it seems to be doing just fine.

Until a few months ago i was using conventional green in both, then the Capri overheated on me one day and when i drained the cooling system i found the radiator was severely clogged with what seemed like Silicate gel / dropout.

My intention was to make a PSA out of this thread warning people not to use 2-Eha containing coolant in cooling systems containing Lead Solder.







I wish they would stop selling EHA2 period. It seems to only be truly compatible with a car that came from the factory with dex and there are a LOT of cars that didn't come that way.

One less confusing item to have to worry about.
 
So, if so many of the coolant additives are harmful if you pick the wrong one, is there anything chemically speaking (since I hated Chemistry class) from stopping you from using a propylene glycol that is phosphate, nitrate, nitrite, silicate, borate, amine free?

It seems to make sense since it's biodegradeable and isn't likely to result in death to stray neighborhood animals who lap it up (ok, so one of those is a plus) Just kidding on the animal thing, but it is a valid concern for people with a conscience.
 
When Dex first came out we saw a ton of cooling system related component failures like heater-cores, Head / Intake gaskets, and radiators. Then it slowed down and now it seems that they fail no more than any other OE so they either made a change to the Dex formulation or components or both. Not sure because we never really tracked it but that is what it was like. Oh and the sludging issues in the beginning. That was terrible as well.

Other OE's aren't exempt from their cooling system fluid change from good old green to other types of coolant / longer life coolants. Chrysler had their fair share of heater-core and radiator failures as well while they ironed out their coolants during the transition from standard glycol to HOAT and then to OAT. Less with the HOAT to OAT but from standard to OAT there were some really big material compatibility issues.

Now keep in mind with the sludging issue this could be related to folks pouring in the wrong stuff that isn't compatible and then fibbing about it however it seemed to be more common on the 60 degree V6's than other models when it first started happening. Maybe a weird anomaly.
 
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Originally Posted by SubieRubyRoo
So, if so many of the coolant additives are harmful if you pick the wrong one, is there anything chemically speaking (since I hated Chemistry class) from stopping you from using a propylene glycol that is phosphate, nitrate, nitrite, silicate, borate, amine free?

It seems to make sense since it's biodegradeable and isn't likely to result in death to stray neighborhood animals who lap it up (ok, so one of those is a plus) Just kidding on the animal thing, but it is a valid concern for people with a conscience.


I believe the reason you need SOME kind of acid is to fight scale build up inside the coolant piping. In the past silicates performed this function by abrasively rubbing against pathways to keep surfaces exposed but with age the particles fall out of suspension.

So then you have a HOAT like G05 that still uses some silicates but also has acid technology. And then you have dex which is silicate free and completely acid based.

If one is good about maintenance then a silicated coolant is fine assuming the system is built for it. Change it out before the silicates fall out and you're good. Whether the base is EG or PG would be of little difference.
 
VW's current G13 and previous G12++ are OAT coolants with About 80% of the Silicates a traditional coolant would have added to the Benzoic and Sebacic acid "backbone"

They also have compounds that stabilize the Silicates and prevent them from gelling or dropping out.

Silicates when properly stabilized do not gel or drop out, the way they work is they passivate metals, the silicates absorb themselves into the metal within 48-72h of entering the system so depletion is sharp at first but depletes slower later.
 
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Originally Posted by Reddy45
Originally Posted by SubieRubyRoo
So, if so many of the coolant additives are harmful if you pick the wrong one, is there anything chemically speaking (since I hated Chemistry class) from stopping you from using a propylene glycol that is phosphate, nitrate, nitrite, silicate, borate, amine free?

It seems to make sense since it's biodegradeable and isn't likely to result in death to stray neighborhood animals who lap it up (ok, so one of those is a plus) Just kidding on the animal thing, but it is a valid concern for people with a conscience.


I believe the reason you need SOME kind of acid is to fight scale build up inside the coolant piping. In the past silicates performed this function by abrasively rubbing against pathways to keep surfaces exposed but with age the particles fall out of suspension.

So then you have a HOAT like G05 that still uses some silicates but also has acid technology. And then you have dex which is silicate free and completely acid based.

If one is good about maintenance then a silicated coolant is fine assuming the system is built for it. Change it out before the silicates fall out and you're good. Whether the base is EG or PG would be of little difference.




I think you are confusing what OAT is, OAT is a broad term that includes various different types of acids, which function as corrosion inhibitors, just like Silicates, Phosphates, Nitrites etc are corrosion inhibitors.

The PH of OAT coolants is lower, around 8 - 8.5 usually, meanwhile a fully formulated IAT coolant would be over 9, but they are by no means acidic.
 
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