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blue or green coolant?

General conversations about BMW E28s and the people who own them.
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simonm11
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blue or green coolant?

Post by simonm11 »

lets talk coolant for e28s, blue or green? orange/pink is def out of the question, am i right?
why? :D
jc72
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Re: blue or green coolant?

Post by jc72 »

The color is just a dye.

The correct coolant from BMW is blue.

Zerex G-05 is interchangable; but has no dye and is clear.
Mike W.
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Re: blue or green coolant?

Post by Mike W. »

The BMW blue is supposed to be a very high quality coolant. But I think in E28 engines it's unnecessary, plain old green works just fine. A cast iron block with aluminum head isn't all that fancy to need special coolant. I would steer clear of the pinks and oranges and other oddball colors along with the Dex whatever from GM. Keep a decent mix in, change it every once in a while and you'll be fine.
Shawn D.
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Re: blue or green coolant?

Post by Shawn D. »

jc72 wrote:Zerex G-05 is interchangable; but has no dye and is clear.
Actually, it's a pale Mello-Yello-ish color. Source: I use it in my 300td and '57 Chevy.
Mike W.
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Re: blue or green coolant?

Post by Mike W. »

Shawn D. wrote:
jc72 wrote:Zerex G-05 is interchangable; but has no dye and is clear.
Actually, it's a pale Mello-Yello-ish color. Source: I use it in my 300td and '57 Chevy.
Yeah, I've used it in an E39 and thought it had color, but wasn't sure enough to say something, nor exactly what it was.
Blue Shadow
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Re: blue or green coolant?

Post by Blue Shadow »

The cars came with an orange coolant but that is before that color was claimed by the Dex-cool camp.
The Zerez G-05 is the correct coolant and is a very pale yellow color and looks just fine while costing less than the BMW Blue-Stuff.
oldskool
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Re: blue or green coolant?

Post by oldskool »

I only worry about the brown acid.
Mike W.
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Re: blue or green coolant?

Post by Mike W. »

oldskool wrote:I only worry about the brown acid.
Blotter or barrel?
alabbasi
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Re: blue or green coolant?

Post by alabbasi »

Provided that you change every couple of years, green coolant is just fine. The other colors are long life chemistry and if you plan to keep the coolant for 7 years or 100k miles. Then go with G05 or the blue stuff. I'm sure that both are good.
bkbimmer
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Re: blue or green coolant?

Post by bkbimmer »

Distilled water and a splash of vodka is all you need.
Dave_in_VA
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Re: blue or green coolant?

Post by Dave_in_VA »

Generally green is good old ethylene glycol, gold/beer colored is HOAT (hybrid organic acid technology) and orange (dexcool) is OAT.

Now according to wikipedia:

Organic acid technology
Certain cars are built with organic acid technology (OAT) antifreeze (e.g., DEX-COOL), or with a hybrid organic acid technology (HOAT) formulation (e.g., Zerex G-05), both of which are claimed to have an extended service life of five years or 240,000 km (150,000 mi).

DEX-COOL specifically has caused controversy. Litigation has linked it with intake manifold gasket failures in General Motors' (GM's) 3.1L and 3.4L engines, and with other failures in 3.8L and 4.3L engines. One of the anti-corrosion components presented as sodium or Potassium 2-ethylhexanoate and ethylhexanoic acid is incompatible with nylon 6,6 and silicone rubber, and is a known plasticizer. Class action lawsuits were registered in several states, and in Canada, to address some of these claims. The first of these to reach a decision was in Missouri, where a settlement was announced early in December 2007. Late in March 2008, GM agreed to compensate complainants in the remaining 49 states. GM (Motors Liquidation Company) filed for bankruptcy in 2009, which tied up the outstanding claims until a court determines who gets paid.

According to the DEX-COOL manufacturer, "mixing a 'green' [non-OAT] coolant with DEX-COOL reduces the batch's change interval to 2 years or 30,000 miles, but will otherwise cause no damage to the engine".[30] DEX-COOL antifreeze uses two inhibitors: sebacate and 2-EHA (2-ethylhexanoic acid), the latter which works well with the hard water found in the United States, but is a plasticizer that can cause gaskets to leak.

According to internal GM documents,[citation needed] the ultimate culprit appears to be operating vehicles for long periods of time with low coolant levels. The low coolant is caused by pressure caps that fail in the open position. (The new caps and recovery bottles were introduced at the same time as DEX-COOL). This exposes hot engine components to air and vapors, causing corrosion and contamination of the coolant with iron oxide particles, which in turn can aggravate the pressure cap problem as contamination holds the caps open permanently.

Honda and Toyota's new extended life coolant use OAT with sebacate, but without the 2-EHA. Some added phosphates provide protection while the OAT builds up. Honda specifically excludes 2-EHA from their formulas.

Typically, OAT antifreeze contains an orange dye to differentiate it from the conventional glycol-based coolants (green or yellow). Some of the newer OAT coolants claim to be compatible with all types of OAT and glycol-based coolants; these are typically green or yellow in color.

Hybrid organic acid technology
HOAT coolants typically mix an OAT with a traditional inhibitor, such as silicates or phosphates.

G05 is a low-silicate, phosphate free formula that includes the benzoate inhibitor.

I normally tell my customers that if flushing and changing the coolant, to go with what the factory fill was but if just adding, to match what is in the vehicle. You don't want to mix dexcool and ethylene glycol.
BRRV
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Re: blue or green coolant?

Post by BRRV »

I researched this a few years ago. I will expand on Dave's comments:

First, G48 (BMW) is blue-green, and G05 (Mercedes-Benz) is pale yellow, according to BASF in its Glysantin descriptions. I've used both, although contrary to reports, they are not strictly interchangeable, although both are now HOAT. And plain old green is flatly unacceptable in a (modern) BMW, according to the factory.

Green anti-freeze is IAT: inorganic acid technology, and it contains both phosphate and silicates, rendering it unacceptable to BMW, which requires "mono-ethylene gycol which is nitrite, amine, and phosphate-free". Now, why? The short answer is corrosion: "Some European automobile manufacturers request that a phosphate-free antifreeze be used in their vehicles. This issue is related to the extremely high mineral content of the water in Europe. If you were to mix an antifreeze that contained phosphates with the type of water they have in Europe, it may produce deposits that can settle in the cooling system and promote corrosion..." Generally, silicates then replaced phosphates for Europeans vehicles.

Now, all of us typically would use distilled water, which might render this point mute. But then we'd be neglecting the additives in the factory-spec corrosion package, wouldn't we? BMW N 600 69.0 states "ethylene glycol based, organic acids and silicates, nitrate, amine, and phosphate free". G48 is the ONLY coolant spec that meets those requirements. G48 uses 2-EHA (a hydrated organic acid salt) and silicates (<250PPM). According to sae.org, G48 is a "low silicate formula with sebecate, a dash of 2-EHA and reduced borate". Interestingly, and this may be why some folks have no problem with using 'green' antifreeze in BMWs, the (BASF) G48 spec is historically dated as mid-1986.

And while G05 is considered an "acceptable" alternative to G48, it is not specifically approved. Why? nitrites, which show a higher "weight loss" of aluminum due to corrosion (glassware and heat transfer tests) than the later-gen G48 without. While both G05 and G48 are, again, considered to be HOAT technology, G48 is the next generation, primarily because of changes in metals used in engines (aluminum, specifically). G05 does not contain 2-EHA, either. By the way, original G05 was not long-life; the current formulation is, and may be similar to Glysantin G40, another BASF coolant spec; it uses SI-OAT technology.

The removal of nitrites from BMW antifreeze with N 600 69.0 was clearly intended to extend the life of aluminum components; nitrite is, generally, an additive for diesel engines. According to some sources, BMW moved to G48 due to issues with plastic incompatibility (water pumps, etc.), and G05 isn't as "friendly" to plastics, based on various reports I've read. Where G05 shines is with cast, grey iron, which really like nitrites, and helps protect from the corrosion caused by water-pump cavitation issues. BMW clearly felt that protecting from aluminum loss was more important that water pump cavitation issues.

The conclusion, then, is that G48 (which is BMW antifreeze) is safe and less corrosive on aluminum components. Last but not least, HOAT coolants can also extend the life of rubber coolant hoses, because they conduct less electrochemical degradation (ECD) than the conventional green antifreeze. ECD is the process by which the motion of coolant and water through your engine creates an electrical charge, similar to a galvanic battery. This electrical charge degrades both rubber and metal parts in the cooling system from the inside out. ECD can be the cause of premature coolant system failures, in the words of some automotive writers.
alabbasi
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Re: blue or green coolant?

Post by alabbasi »

BRRV wrote:G05 isn't as "friendly" to plastics, based on various reports I've read.
And we all know how important that is on modern BMW cooling systems. Mercedes Benz actually just moved to blue coolant in the last couple of years. Again if we're talking about E28's and you plan to change the coolant every couple of years. Green is fine and certainly better than not changing at all.
BRRV
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Re: blue or green coolant?

Post by BRRV »

I I think the question is, really, why would you? Use green, I mean. Sure, you can, with a caveat: distilled water wouldn't be a recommendation, it would be a requirement. And, if green, why not split the difference and use G05, which, save for nitrites, is considered to be a more compatible coolant, and cheaper than G48? I personally use G48 now, but have used G05 in the past without worry. If I was using green, I'd be changing it yearly, and I think the cost and the hassle of doing a full, complete change every year makes using G05 or G48 a more logical, certainly a less troublesome, alternative, for all the reasons mentioned already. We all know that aluminum in our cooling systems is expensive and difficult to replace. This is the reason, in my forever E28, I use G48.
alabbasi
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Re: blue or green coolant?

Post by alabbasi »

BRRV wrote:I I think the question is, really, why would you? Use green, I mean
I still use green (Well Preston which is greenish and long life) on some of my cars. For the simple reason that I can walk into any store (not just an auto store but a grocers, or hardware store) and pick some up. This means that it's available to me pretty much wherever I am , 24 hours / day.

Some retail auto parts stores sell G05, I've not seen any sell G48. If for any reason you need to add coolant while you're in transit, it's the lowest common denominator. It still does a pretty good job on older cars provided that you stay on top of maintenance schedules.
Dave_in_VA
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Re: blue or green coolant?

Post by Dave_in_VA »

I sell the Pentosin http://www.pentosin.net brand which is actually Deutsche Pentosin-Werke GmbH.

They recommend their Pentofrost NF for all BMWs. http://pentosin.net/specsheets/Pentofrost_NF.pdfIt is, and I quote, "Pentofrost NF is an environmentally friendly Antifreeze
concentrate for multipurpose applications in water-cooled engines. It does not contain any nitrites, amines or phosphorous additives. Pentofrost NF protects all material used in cooling systems and is recommended for non-ferrous metals and year-round use. Meets ASTM D-3306".

I have not used it personally but I do have some customers that swear by it, Which is a refreshing change from the "is that the cheapest you got" mentality of the majority of my customers.
BRRV
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Re: blue or green coolant?

Post by BRRV »

I can buy the Pentasin here at my NAPA; I can also get it at PepBoys (as I can G05). But it's more expensive than even the G48 BMW coolant. Honestly, while I carry a gallon of pre-mixed G48 in the car, the haven't touched it since I made the last change in '16. In any event, unless it's below freezing, you could always get away with distilled water until you got it home.
a
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Re: blue or green coolant?

Post by a »

It is moot now. Purists may cringe, But I never had any trouble running parts house store brand coolant cut in half with my iron rich well water. I did a coolant change as a part of base lining a new daily driver. Other than normal old car stuff, drips, etc. I
have had only one water pump failure. And that was managed easily with well water in some gallon jugs. E 28s were easy on cooling systems. And with a Low Coolant light there is no excuse to ever overheat the engine. I have yet to pull an M20 head.
wkohler
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Re: blue or green coolant?

Post by wkohler »

Honestly, how big a deal is the price difference for something you change out every couple of years? $25/gallon and a $.99 gallon of distilled water and you're good and you don't have to worry. The last thing I need is another fluid that isn't instantly recognizable. I run the G-05 in the Volvos but I use the blue stuff in my cars. The '99 M coupe had Evans waterless coolant in it and I don't understand that stuff at all. Supposedly never wears out, but I don't really want to put it back in.
simonm11
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Re: blue or green coolant?

Post by simonm11 »

wow! good info here, thank you guys. always learning!
Karl Grau
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Re: blue or green coolant?

Post by Karl Grau »

alabbasi wrote:I still use green on some of my cars. For the simple reason that I can walk into any store (not just an auto store but a grocers, or hardware store) and pick some up. This means that it's available to me pretty much wherever I am , 24 hours / day.
I'm pretty old but I can honestly say that there has never been a time in my life where not being able to buy antifreeze at 3:00am on Sunday was an issue. :laugh:
vinceg101
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Re: blue or green coolant?

Post by vinceg101 »

Dave_in_VA wrote:I sell the Pentosin http://www.pentosin.net brand which is actually Deutsche Pentosin-Werke GmbH.

They recommend their Pentofrost NF for all BMWs. http://pentosin.net/specsheets/Pentofrost_NF.pdfIt is, and I quote, "Pentofrost NF is an environmentally friendly Antifreeze
concentrate for multipurpose applications in water-cooled engines. It does not contain any nitrites, amines or phosphorous additives. Pentofrost NF protects all material used in cooling systems and is recommended for non-ferrous metals and year-round use. Meets ASTM D-3306".

I have not used it personally but I do have some customers that swear by it, Which is a refreshing change from the "is that the cheapest you got" mentality of the majority of my customers.
I used some of the NF this past July when driving back from 5erWest. I had to stop and pick up more coolant as I was burning through the green Prestone that we used in the blown hose emergency (thanks again to Kohler and Eric for rescue on that). It seemed to perform a little better but it was hard to tell what was going on with engine on that trip (i.e. I wasn't mysteriously losing as much blue NF nor was it running as hot as I was when it was green :dunno: ). Both were 50/50 cut with distilled. (Oddly one of my over riding decision drivers for going with the NF was that it comes in smaller bottles than the other stuff; I couldn't stomach buying a whole gallon of green only to never use it again.)
I flushed out the whole block thoroughly when I got back and replaced it with 50/50 BMW blue as it should be.
SPF2006
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Re: blue or green coolant?

Post by SPF2006 »

Dave_in_VA wrote:I sell the Pentosin http://www.pentosin.net brand which is actually Deutsche Pentosin-Werke GmbH.

They recommend their Pentofrost NF for all BMWs. http://pentosin.net/specsheets/Pentofrost_NF.pdfIt is, and I quote, "Pentofrost NF is an environmentally friendly Antifreeze
concentrate for multipurpose applications in water-cooled engines. It does not contain any nitrites, amines or phosphorous additives. Pentofrost NF protects all material used in cooling systems and is recommended for non-ferrous metals and year-round use. Meets ASTM D-3306".

I have not used it personally but I do have some customers that swear by it, Which is a refreshing change from the "is that the cheapest you got" mentality of the majority of my customers.
I've used the Pentosin NF most recently on my previous Volvo 850 fwiw, and would certainly use it again.
alabbasi
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Re: blue or green coolant?

Post by alabbasi »

Karl Grau wrote:
alabbasi wrote:I still use green on some of my cars. For the simple reason that I can walk into any store (not just an auto store but a grocers, or hardware store) and pick some up. This means that it's available to me pretty much wherever I am , 24 hours / day.
I'm pretty old but I can honestly say that there has never been a time in my life where not being able to buy antifreeze at 3:00am on Sunday was an issue. :laugh:
And if we were to go on the premise that if you had not experienced it then it can't possibly be considered then we would all be in agreement :)
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