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G12 Goop Solvent Thread

6K views 49 replies 21 participants last post by  Electron Man 
#1 ·
#2 ·
I'm no chemist, but have heard that Dexcool used to cause deposits. Enough so they actually had a cleaner for it, GM P/N 12346500 (now discontinued) used "oxalic acid as the powder, washing soda was the neutralizer". I found in another thread : " The GM stuff is actually Prestone P/N AS100 Heavy Duty Cooling System Cleaner". Another: "The old two-stage product (Prestone AS100=GM pn:123465000 or something like it) has been replaced with the new, one-stage product (pn:88861344)."

Quotes taken from an internet search, did not verify. And some threads were from 2009-ish, so not sure how compatible with VW's coolant system.
 
#3 ·
I have a tankless hot water coil in my boiler . I also have very hard water ( calcium ) . Calcium builds in the coil as the water is heated and eventually clogs the coil leaving me with no hot water . I found a product called " sizzle " that disolves the calcium
. It not for amatures for sure . It's hydacloric acid , but when diluted and pumped through the coil it dissolves anything . It will eat through a completely cloged coil and restore full functioning hot water to the house .
 
#5 ·
I have a tankless hot water coil in my boiler. I also have very hard water ( calcium ).
The residue in question is most likely of an organic nature...
A chemical that dissolves calcium/minerals may or may not have much effect on the G12/Prestone goop. I know acetone is a strong solvent, but that doesn't necessarily mean it will dissolve our goop. That's why I'm hoping someone with a chemistry background can lead this charge. Different substances are dissolved by different things and an understanding of chemistry helps determine which solvents will work on which substances.

When I was a late teen I did mechanical for a chain of dry cleaning plants. In a plant there is a position called a "spotter". The spotter specializes in removing spots and stains from garments. They have a selection of various solvents and chemicals they use to do this. Each type of stain had a chemical formulated to work on that specific type of stain. I remember one chemical was called POG (Paint Oil Grease). Another was called Protein and was formulated to work on stains like blood or grass. When they put the correct chemical on a stain, it broke it down or dissolved it. We need to figure out what dissolves goop. Or in other words, in what chemical, will goop go into solution.
 
#4 ·
The residue in question is most likely of an organic nature...meaning you probably won't have much success completely dissolving it with CLR, citric acid, weak muratic (hydrochloric) acid or vinegar. Some of it perhaps, but not all of it.

Not to change the thread direction, but I'm a little more confused about how people who've never had oil/coolant mixing issues (failed heat exch.) or who've never mixed Prestone with G12 end up getting sludge out of their heater core (HC). I realize the HC is a "well" for catching any solid material that may form, since it tends to settle there. I guess the G12 degrades by itself somehow(?)

I really wish there were something like Stoddard solvent (mineral spirits), lacquer thinner, Acetone :O or something similar with a flash point above ~300 F so we could safely put it into our cooling systems, drive around for a half hour, then drain the coolant sludge mixutre.
 
#7 ·
Not to change the thread direction, but I'm a little more confused about how people who've never had oil/coolant mixing issues (failed heat exch.) or who've never mixed Prestone with G12 end up getting sludge out of their heater core (HC). I realize the HC is a "well" for catching any solid material that may form, since it tends to settle there. I guess the G12 degrades by itself somehow(?)
Do we know this for a fact?

Let me explain what I mean: most oil change places are checking fluids and sometimes adding if necessary. Most of the people working there don't know that coolant and P/S fluid is different than the generic one.
 
#6 ·
Throwing in another constraint for the "ultimate solvent" here since it crossed my mind. Whatever is used must be "friendly" to the water pump seal and coolant hoses if it will be in the cooling system for very long.

If the goop is viscous but pumpable, in your opinion Steve, I'm gonna go out on a limb and loosely classify it as an emulsion. I wonder whether Amour All Purple cleaner would break the emulsion up...without doing too much damage to aluminum while it's hot. :nervous: I recall this stuff will dissolve oil and grease even when diluted.
 
#8 ·
Is Armour All Purple Cleaner the same as any of those multi cleaners? Like Simple Green and the like? Some of those I've used seem like degreasing detergents.

Detergents, like soaps, work because they are amphiphilic: partly hydrophilic (polar) and partly hydrophobic (non-polar). Their dual nature facilitates the mixture of hydrophobic compounds (like oil and grease) with water.
I have some G12 and I have the yellow kind of antifreeze. First I'm going to try creating a sample batch of goop. I don't know if the two coolants curdle straight off or if they need time or heat or a catalyst to do so. Then I'll see how multi cleaners effect it.

 
#9 ·
I'm not a chemist, but my father was. I picked up enough to know that a strong solvent for one substance may be completely ineffective for another. I would suspect the "goo" we're talking about is along the lines of complex molecules of some minor additive in both coolants linking up to form a semi-solid; an organic emulsion, as mentioned. I would expect grease-cutters, petroleum-based solvents, and acids would all be useless. Something that breaks down the bonds created.... Hmm. I have a gallon of G12 in the shed, as well as one of Prestone left by the previous owner. I also have an enzyme-based cleaner for bird cages. I'll let you know in a day or two. Right now the shed door latch is frozen.
 
#12 ·
http://www.amazon.com/OTC-6043-Blast-Vac-Multipurpose-Cleaning/dp/B000F5ECRW

Not a solvent, but a good way to force the crud loose. If deposits are simply lodged in place from stacking up, a little convincing would help.

I wouldn't recommend anything too acidic for these systems as it has a plastic flange first then its mounted to an aluminum heat exchanger. I'd say a reduced acidic solution to break down any material, then a harsh flush with the above Blast Vac.
 
#14 ·
Does anyone have the chemical formulas for G12 coolants and the Prestone coolants? Might be helpful to know what kind of reactants were are looking to break up, instead of just speculation.

A few observations or perhaps summaries of other members' posts:

1) since both G12- and Prestone-type anti-freeze products are water soluble or are able/recommended to be diluted with water, then I would think that both are classified as solutions, and not compounds. it would stand to reason that the coolant molecules are not fundamentally changed by their mixing with water, but they could be catalyzed to change by interaction with impurities if distilled water is not used.

2) mineral- or petroleum-based solvents are going to have a hard time reacting with coolant molecules in suspension with water. It will take a serious amount of agitation to get reactants to meet in a solution, so I would think that whatever would possibly work is going to have to able to be mixed in solution with water so it can effectively dilute any standing fluid and act on goop.

3) CLR and other de-scaling/de-calcifying agents are acidic, but they typically do not react to plastics (hence they can be stored indefinitely in polymer containers). Acids do react with rubber, as do mineral- and petroleum-based solvents, so their use is ill advised (never use vaseline to dress your jim hat.)

So I would hope that the target reactants are organic and have a simple soluble achilles heel agent that can break them up, e.g. a strong detergent.

Purple Power is my go to degreaser and is not displaced by water. Something in it puts off some nasty vapors, but it hasn't been unkind to any surface I have put it on, plastics, aluminum, latex included.

Lye perhaps? TSP?
 
#15 · (Edited)
As important as the chemical composition of these coolants is and what reactions take place between them to form goop, the nature of the goop itself is just as important, if not more so.

It would be important to have a reliable way to create goop on the bench -- is that straight forward to do? Does anyone have a recipe?

- Is mixing them in a cup sufficient?
- With heat?
- Under pressure?
- Under heat and pressure?
- In repeat cycles?
- How fast does it form?
- What are its physical properties? (stick it in the freezer, heat it above 200, 300, etc)
- Does it require the presence of some other impurities to act as catalysts?

It may be possible that whatever chemical weak point exists in the molecular structure of the goop, it may harm the various metals and other materials of the heater core. The resulting "solvent" may need to weave a fine thread across all this in general, but in this case, what's the heater core made of? Plastic, aluminum, .... what else? Is there any copper alloy in there? I wouldn't expect rubber to be inside there.

Purple power is mildly corrosive to aluminum if I am not mistaken. I love it as a low-foaming solvent and spray it like there is no tomorrow, but more than 10 min., it will cause pitting in aluminum. I tested this on some old parts.

Is there some mechanical means of breaking it apart? Will a fine water jet be able to brake it up?

And if goop is organic in nature, some enzyme will be necessary I would think. It's not trivial to create an enzyme that easily, but it might be possible to use readily available ones. Some powders for toilet drains and septic tanks have enzymes that eat away at cellulose, and other organic matter.
 
#16 ·
It would be important to have a reliable way to create goop on the bench -- is that straight forward to do? Does anyone have a recipe?

- Is mixing them in a cup sufficient?
- With heat?
- Under pressure?
- Under heat and pressure?
- In repeat cycles?
- How fast does it form?
- What are its physical properties? (stick it in the freezer, heat it above 200, 300, etc)
- Does it require the presence of some other impurities to act as catalysts?
Tonight I mixed 50/50 Pentosin silicate free G12 and generic green ethylene glycol antifreeze in a plastic cup on a bench. It just turned light brown and nothing else. I'll let some sit and I'll heat some in a microwave. I'm hoping it's easy to form goop. It seems to be easy enough when you do it in an engine. :banghead:

Once we can make goop, we can look for something that will break it down.
 
#18 ·
I think you are better off mixing used G12 (I.e. 80,000 mile old) to stack the deck so to speak. I have read but really don't know how much its properties deteriorate over time. I also suspect whatever contaminants develop over time in the cooling system may play a role. Maybe scrape the insides of an old coolant flange or crystals of a plugged up heater core. I'd also try to do this in a pot instead of a microwave (maybe those radio waves interfere with bond formation in some way). Maybe add some minerals or hard tap water. Maybe the prestone needs to be old too, or in larger proportion to G12.

Do we know how long it takes for gel to form in actual cases? The threads I found don't say.

A different tack might be to obtain some goop and drop it into a mix of g12 and prestone and see if heat cycling all that would cause the coolant mix to also gel.
 
#21 · (Edited)
It would probably be a PITA but I would simulate the hot cold cycles. Even if that means heating the solution to operating temps and then taking the pan outside to cool.

If I had money, and didn't live in a dorm I would do the following:

Use the pan and heat the solution to operating temp 190?

Bench set an old automotive water pump and drive it by an old electric motor.

Use OEM spec coolant lines to run the solution from the Pan though the pump to an old (new?) heater core and have the return feed go back to the pan. Run a house fan over the heater core as if we where actually using the heat so we have some heat exchange.

Get one of those electric socket timers and set your duty cycle off time ratio. Feed it all from a single power strip so everything just runs.


---Or after doing some reading----
Hypothesis:

Neglected cooling systems are more subject to cavitation, this coupled with the addition of non OAT coolants work to devolve the metals dislodged in the process more quickly which leads to the creation of our goop!

Testing: Using an aluminum container bring to a boil a 50/50 mixture of non-OAT antifreeze and water. Strain solution and examine container for pitting. Examine strainer for goop. Do this test outside far away from anything living in a HIGHLY ventilated area. Breezing antifreeze vapor would be extremely bad.




------G12 Chemical Data-------


Sunoco Europe
http://www.sunoco.be/PDF/UK/MSDSUKAntifreeze G12.PDF

PH @50% : 7.9
Makeup:
***Ethylene glycol - 91%-96%
***Inhibitor Additives - Remaining.

Pentosin
http://www.pentosin.net/pressreleases/PentoFrost SF Antifreeze 1-11-11.pdf
http://www.pentosin.net/msds/Pentofrost SF.PDF
http://www.pentosin.net/specsheets/Pentofrost_SF.pdf

PH@50% : 8
Makeup:
***??
----------Regular Chemical Data-----------
Peak
http://images.peakauto.com/auto_conventional_antifreeze_coolant msds.pdf

ph@50% 10.5-11
Makeup:
***Ethylene Glycol 90-95
***Diethylene Glycol 0-5
***Dipotassium Phosphate 0-2


Prestone
https://www.lakeland.edu/PDFs/MSDS/18/Antifreeze (All Brands).pdf
Ph@50% Not Determined |However people say in there tests 8.8|
Makeup:
***Ethylene Glycol: 80-96
***Diethylene Glycol: 0-8
***Other..

Other Data:

It is not a good idea to mix an OAT coolant with a traditional [green] silicated coolant, or any silicated coolant for that matter. This is what can cause gelling, sludge, and gunk buildup, in addition to a neglected OAT system (caviation)
http://www.audiworld.com/forums/a6-...w-g-12-glysantin-g-30-europe-coolant-1691297/

When water and coolant in your engine heats and expands, air bubbles are formed from localized boiling. The general term we often use is cavitation. The scientific term for that specific localized boiling I mentioned is nucleate boiling. – I can’t believe I found a picture of this! These bubbles collapse or explode against the outside of the cylinder liners and take a portion of the steel with it. This is called cavitation erosion. These little bubbles are imploding at the cylinder liners at pressures up to 50,000+ psi. They start blasting into the cast iron liner and causing a “pitting process” that continues over and over until they tunnel their way into the combustion side of the cylinder.
http://www.thedieselstop.com/forums/f67/cavitation-coolant-sca-information-202709/
 
#22 ·
If the 50/50 mixture of EG and water is boiling uncovered on your stove, you'll be fine (no cause for alarm). The normal (atmospheric pressure) boiling point of pure ethylene glycol is 198 degrees Celsius (about 388 F). NBP for water: 212F

Most of what's coming off a boiling pot of 50/50 mix will be water vapor...probably not much worse than 98% steam, 2% EG. As long as you're not standing over the pot for 8 hours, you'll be fine.

If you maintain the proper coolant/water ratio, the only nucleate boiling that will ever occur is in the passages of the cylinder head on a July day while the car is idling with A/C on at a stop light (i.e. no air flow through radiator). Cavitation does not happen at the water pump unless you're running a low coolant/water ratio (less than ~10 percent coolant - who does that?). People also often forget that the boiling point is raised in a pressurized system.

A water pump will provide all the agitation you'll need to form an emulsion (if that's what the goop is). And one other thing....first time I've had an opportunity to use this one...

:pics:

...of the goop that is. :D
 
#24 ·
I think it has to do with mixed chemicals and different metals in the engine. You've got an aluminum alloy head, a cast iron lower block, aluminum alloy radiator and heater core, rubber hoses, and plastic flanges (ABS plastic?) So, it could be any of those things that its reacting with. Heater cores don't clog over a few days of having mixed coolants, it takes a few years as far as I can tell. Plus, its a mix of heat cycles, pressure changes, climate conditions (cold/hot starts,) and the way a driver drives that affects a lot of that. I'm not saying it is impossible to develop this "goop," but I will say it will be hard to replicate the conditions. I'm not trying to be a doubter, but its just part of the scientific process. You have to know and replicate all your variables and constants in order to get an accurate and meaningful result.
 
#25 ·
You'd only need to replicate the things required to form goop. We don't yet know what those things are. Two incompatible coolant types and... ? Heat may or may not be a factor. Same for exposure to metals. We won't know till we strike on a productive recipe.

To answer Paul... I've never had a blocked core myself, but when I first got my car, the coolant was brown with almost powdery sized stuff suspended in it. Whatever was in there wasn't clean G12 or Prestone. I'm guessing a mix of the two. The car had just had a head replaced and timing belt done, but the coolant certainly wasn't new. Sometime back, someone posted pictures of a core cut in half with blockage exposed. I need to see if I can find that thread. I don't remember if his blockage was goop or calcium or rust or what.
 
#26 ·
My wagon was the same. Brown with specs, but no sludge. A hose to the front with the thermostat, water pump and all hoses removed flushed everything out without needing any solvents. That was 8 years ago and I swapped to Peak coolant at that time. No further indications of clogging and the heat works great. I am replacing the heater core as it leaked at the hose connection. The replacement coolant looked great and I have changed it every couple of years since.

Since I will have the dash out for the 1.8T/manual wiring harness, I am pulling the heater core at the same time. The clogged cores I have seen have been calcium and/or rust.
 
#27 ·
Here is a link to the previous heater core cutdown I believe Steve was thinking about:

http://www.passatworld.com/forums/b5-garage/338139-heater-core-teardown-pix.html

I think PZ's method of flushing may have a great deal to do with his success: getting rid of so much of the dead volume and using continuous flow makes it far more complete with little residual volume of old (incompatible) coolant left.

Just draining from the radiator petcock on a 1.8T once gets less than half the 7 liter volume of the system out: to get approximately 5% residual old coolant requires 4 or more complete flushes with perfect circulation and mixing of the coolant every time. Even removing the thermostat is good for about 60% removal only.

Standard machine flushes are good for 70-80% replacement, which empirically isn't enough (I won't go through all the details of my one experience with this unless someone really wants TMI.)
 
#28 ·
Ethylene glycol and propylene glycol have very similar properties in water, and have similar bonds and chemical reactions as well. If you're all looking for a safe way to possibly 'de-sludge' your coolant or at the very least prevent it from turning color, there's a super simple fix. Open the petcock on your radiator and drain about one gallon of your existing coolant mix out. Close the petcock valve, and refill your coolant overflow with one gallon of white cider vinegar from your supermarket. Vinegar has a boiling point of 244 degrees btw. Turn on your car, and drive for about 5-15 minutes to get it up to operating temps and to circulate the fluids. Park, drain/flush the whole system(as described above) and then refill with the proper pink G12 mix. the mild acetic acid in vinegar will decompose any organics which have begun solidifiying, as well as strip off any/some latent build up of deposits from rubber hose internals, without causing harm. Not sure why this hasn't been put out there yet....
 
#31 ·
Before doing that, I'd suggest mixing 1 part vinegar with 3 parts 50% G12 and checking the pH by sticking in a strip of acid range pH paper (approximately pH 5 to 8). I think you'd find it pretty worrisome.

Straight G12 starts out in the mildly alkaline range (pH 8.0 or so). Aging antifreeze of any type becomes more acidic (lower pH) over time and there are quite a number of articles out there suggesting that pH<7 for any coolant chemistry is an indication for flushing and replacement. By contrast, household vinegar, which is 5%-8% acetic acid, clocks in at around pH 2.2.

Since the proposal of draining and refilling once exchanges about half the volume of the 1.8T cooling system (7 liters), you'd end up leaving half a gallon of vinegar in the cooling system if the procedure were done as you describe. If so, it seems pretty certain that the pH of the system would end up way under 7.

You could certainly do a good deal more flushing to remove the residual acetic acid more completely. But if you didn't, you'd be eating up the much if not all of the initial buffering capacity of new coolant.


http://www.pentosin.net/specsheets/Pentofrost_SF.pdf
Learning Coolant Fundamentals
 
#33 ·
Any "aggressive" way of cleaning would involve something rather corrosive for the system, so multiple "rinses" are needed. The recommended method of CLR is probably a lot worse than vinegar.
There is the other method of rinsing, like PZ (I think) suggested: disconnect some hoses and circulate water through different parts of the system.
 
#34 ·
Whatever cleaning agent is put into the system is only in there temporarily. The key is to make sure it gets flushed out completely. Even strong or corrosive (within reason) agents are OK if they are only used short duration and rinsed out thoroughly.

After the system is drained as best as it can be, I like to flush with constantly running water. I open up the system in several places then take a garden hose on full flow and flush, flush, flush. Forward flush and reverse flush every path through the system.

Someone above noted that the system will retain some liquid even after a thorough draining. If you like, you can use a shop-vac to suck out some of the remaining pockets of liquid from the system. You'll never get all of it but a strong vacuum flow will move more of it out then just gravity draining. I tried this on my truck at the last flushing. I did it the same way I was flushing through various openings in the system with the water hose, but with a running shop-vac instead. I think I got an extra couple quarts or so out with the vacuum. The more volume of flow you can get going, the more liquid the airflow will carry out.
 
#35 ·
This site does a nice job of explaining the differences in coolant technologies. The end of it explains the goop: Coolant/Antifreeze.

Basically, the precipitate is silicates (think sand) so solvents won't help with that. the reason I think it gets the "goop" moniker is because the ethylene glycol is slippery feeling and the very small silicate particles provide a lot of surface area for it to stick to. Effectively making a mud like substance.

If you didn't use distilled water to dilute it, you may very well have some calcium and other minerals that would scale. CLR and other acids will dissolve this and may get things moving.

Based on this, I would say applying some pressure to the material in the core may be better at cleaning it than solvents.
 
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