Ball joint

iTrader: (6)

ok buddy seriously theres one thing to attack his theory which is fine after all this is quite a heated debate. But why would you attack him for something that he odviously just fucked up trying to say. Personally when I read that sentence (by the way I know its not a complete sentence so dont define sentence for me) I know he said it wrong but I still got what he was trying to say. Look what iam trying to say is if your gonna attack him on his theory at least choose something worth while.

By the way if I fucked up at saying something or forgot to put a comma somewhere I hope you dont discard what I said because its not "educated enough" because to be honest iam typing on a forum and I dont give a ****

DaedelGT

In short, no way in hell. Acids and Bases when put into contact will neutralize each other. A pH of 8.7 contains 0% acid.

dgeesaman

iTrader: (7)

Agree

No, I don't think this is a reasonable assumption. It doesn't take much in the wild confines of an engine to make it much different from the air-cooled engine bay. We have to be exceedling careful before blanketing the theories from one to the other.

Dave

dgeesaman

iTrader: (7)

I'm glad Mr. Stock spoke up. Ron had not until his last post provided any solid support for his ideas. Not that anyone expects a long technical paper complete with equations and figures, but his ideas were disjointed at best. I still think it could have been boiled down to a few simple lines of explanation and saved a lot of headache.

I'm very glad Ron wrote a decent explanation of his idea. Up until that point I didn't think one existed. I'll address my questions about it elsewhere.

I am strangely disturbed by people with technical backgrounds getting losing their objectivity and getting childish. Tends to shake my trust in decision-making ability.

Dave

johnchabin

iTrader: (2)

I think what is being said is that 8.5 is more acidic (or, I suppose, less basic) than 10.

dgeesaman

iTrader: (7)

Ron:

The Bates article and your explanation leave out how a galvanic environment cause ECD. Could you explain this (at least in regards to your situation?)

As well, there is one key difference I'd like addressed - in hoses, the coolant-filled hoses are part of the circuit - connecting the radiator to engine block. In the rotary case, I don't see how the o-rings are part of the circuit. I can see there is a circuit, but I can't see why o-rings would be in any configuration other than parallel to the galvanic current flow.

Also, regarding the alkalinity of the coolant - it's possible that it's (part of?) the problem. But how is acidity related to the galvanic effect? I'm rusty on my galvanic chem, so it might be quite simple.

paw140

By similar enviroments I was referring to the fact that both o-rings and hoses are rubber parts that are in contact with coolant. But as a bunch of you guys keep bringing up, the main difference in the environment with respect to the ECD theory is that coolant hoses connect a circuit between two dissimilar metals, while o-rings do not.

So now we have two theories: ECD and acidic degradation. These are completely separate and should not be confused. After all of this discussion, I don't see how ECD could be occuring, but acidic degradation is certainly possible.

About the PH questions... 1 to 7 is considered acidic, 7 to 14 is considered basic, but 8 is still more acidic than 10. It's all relative. For example, water can act as a weak acid and a weak base, since it can be both a proton donor and a proton acceptor. There is no cut-and-dry definition to define something as an acid and a base in some cases.

I *do* like the idea of Kalrez o-rings, although I don't think they would be readily available. If anyone is interested in the technical data of Kalrez and Viton, they are both manufactured by Dupont, and they have info on their website at www.dupont.com.

dgeesaman

iTrader: (7)

Thanks, that's what I meant to say but didn't write

This is the key issue I have with Ron's presentation - is it acidity breaking down things, or galvanic? Or if they are related, then how?

Dave

RonKMiller

We actually have three, like I said before:

"So now we have an acidic solution, a pronounced galvanic reaction and heat all working together to start ECD."

ECD is the END RESULT result of electrochemical attack.

What proportion each has on the eventual failure is difficult to assess, but they are know factors, and my best guess is that the solution in constant contact with the polymer would be the biggest player. There may be other factors that contribute to ECD like ozone or polar solvents like alcohol, ketones or esters that are leached from the components over time. Whether or not they exist in the coolant fluid "environment"is difficult to say without extensive testing.

Alien7

iTrader: (1)

Rhode_Dog

could anyone guess to how much a set of custom Kalrez O rings would run?

dgeesaman

iTrader: (7)

Two or Three. Heat drives affects the rate of these reactions, no? I could see it being a third mechanism if it actually 'burned' or melted the seal, but we haven't discussed that. Is a failed seal visibly burnt or melted, or just mechanically weaker at the failure point? Ron? Others?

OK, now correct me if I'm wrong. ECD (according to Ron) is the generic term for a polymer or rubber seal losing it's mechanical properties by either a pH- or galvanic reaction. Ron, is this because chemical compounds mixed into the rubber are being leeched out or broken down by the electrochemical environment? Or are advanced o-ring compounds essentially one type of molecule? Either way, shouldn't a chemical analysis of a failed o-ring tell us
1) which compounds have been removed
2) the effects it had on the seal's properties
3) remnants indicating which chemical process is to blame.
I wonder if analysis of the coolant might also tell us about it. I'm sure Bates has some data, but they're not sharing it.

Basically, Ron's thesis (or "I think I've finally figured out the problem") narrows the cause down to either galvanic or acidic conditions eating up the seals, and packaging it under the term 'ECD'. We have seen no data which will prove or disprove it.

Dave

johnchabin

iTrader: (2)

Whoa, just a minute...

This phenomenon is known as electrochemical degradation, or ECD. It occurs because the hose, liquid coolant (ethylene glycol antifreeze and water), and the engine/radiator fittings form a galvanic cell or "battery."

This chemical reaction causes microcracks in the hose tube (see Figure 1), allowing the coolant to attack and weaken the hose reinforcement. Accelerated by high-heat and flexing, the hose can develop a pinhole leak or rupture under normal pressure.

Figure 1

This is from:
http://www.gates.com/brochure.cfm?br...ocation_id=541

Now, if you don't have the "battery" as defined above, you don't have ECD. Period.

You don't have a "battery" with an o-ring. Thus no chemical reaction, no microcracks, and no ECD. Cause and effect.

dgeesaman

iTrader: (7)

OK, thanks. I tried to review everything quickly but somehow I forgot that important point. This supports the conclusion that galvanic processes have no effect on the o-rings. I'm not a galvanic specialist but I certainly don't see any comparable potential in the o-rings compared to the radiator hose scenario.

That would eliminate the 'new' ECD angle and leaves good'ol thermally-accelerated mechanical or chemical (pH?) means.

Dave

EricM

Dude, open up your chemistry book again. As I remember it log [OH]- determines pH. The higher the concentration of hydrogen ions, the more oxygen rich it is and the more "basic" it is. And vice versa for acid. So a pH of 8.7 would mean that concentration of hydrogen ions is higher than water but still less than a liquid with pH of 12. In other words, a liquid with a pH of 8.7 is more acidic(or less basic whatever you choose) than a liquid with pH of 12.
Hope that makes sense.

RonKMiller

John, you most certainly do have a "battery" as defined by Gates. It may or may not exist in the space between the aluminum and iron housing and the O ring, (although I think it does) but it certainly exists in the larger picture of the cooling system.

The "battery" CAUSES the PH of the coolant solution to change to mildly acidic: The solution IS in contact with the polymer 24/7, day after day, mile after mile, year after year. There are electrons swapping orbits all over the place! This is what the Gates site is saying when they talk about "electrochemical attack" (read it CAREFULLY) - not actual electrical current flowing through rubber causing it to degrade! (although it probably does, but the voltage and amperage is insignificant compared to the acidic chemical exposure of the polymer to the coolant solution.)

For those not easily bored by the mundane, here is some additional information regarding chemical attack on polymers (AND SPECIFICALLY WHEN IT COMES TO O RING COMPOSITION) stolen from www.AppleRubber.com: You'll have to dig out the excerpts yourself but it's all there.

"...Resistance of elastomers to chemical attack is greatly reduced at elevated temperatures. Regardless of all other critical design factors, if the basic composition of the O-ring material is not compatible with its chemical environment, the O-ring will eventually fail.

A primary step in O-ring selection, therefore, is to match your application's chemicals with the O-ring material that offers the best chemical resistance. A major consideration for O-ring material selection is resistance of specific elastomers to degradation by exposure to certain chemicals.

Over time, irreversible chemical changes occur that increase seal hardness as well as induce compression set and volumetric changes. (microcracks)

As water is converted to steam, O-ring elastomers are exposed to the degrading effects of heat, in addition to water swell. If heat ranges are exceeded, O-ring materials may assume the condition of a sponge, soaking up gases and fluids, (coolant...) leading to a partial or total loss of sealing properties.

Concentrated Acids at Elevated Temperatures:

A number of elastomers possess good resistance when exposed to dilute acids at room temperature.

These materials include Aflas™, Butyl, Epichlorohydrin, Ethylene Propylene, Fluorocarbon, Fluorosilicone, Hypalon®, Kalrez®, Chemraz®, Natural Rubber, Neoprene®, Nitrile, and Teflon®.

THE ACID RESISTANCE OF THESE COMPOUNDS, HOWEVER, SIGNIFICANTLY LESSENS WITH BOTH INCREASING ACID CONCENTRATIONS AND RISING TEMPERATURES. (not my caps - theirs)

The end result: ECD, IMHO

Any luck with your contacts within Gates? It sure would be nice to hear the opinion of their engineers on this issue. Tell 'em the beer is on me -
I'm only a stone's throw from Denver.

pomanferrari

iTrader: (1)

I was stupid enough to buy into that Dexcool **** for 2 years. Dexcool uses some type of acid that under temperature prevents corrosion of certain aluminum. However, Chrysler switched back to the green stuff according to an article in Car and Driver back around April to July of 2002. I think Dexcool might have accelerated the damage because I started seeing this black polymeric crap collecting inside the radiator neck and cap.

The car was never overheated. I have an Autometer and a VDO temperature gauge at inlet and outlet of the cooling system. I've run high boost 14 psi for the last 3 years. Other than that, it was a gradual deterioration. Blockweld only helped for about 3K and then it was back to the coolant buzzer.

I'm debating about running Evans but from what I hear, your normal temperature is 20 degrees higher than with water so I'm leery at this point.

RonKMiller

Bummer.

The more I think and read about this whole situation I am inclined to go with teflon encapsulated O rings and PH adjusted distilled water and glycol, changed yearly.
I guess it just has to do with Evans being so "new" on the scene. I need to read more about it, and especially the effects after several years of use.

I would also buy the Gates hose instead of OEM since it seems like they have made significant advances in the EPDM formulation. I've trusted their brand for years, and have often gone out of my way to find their stuff. It appears they have replacements available for the majority of larger, pre-curved hoses for the FD3S.

Some of the newer O ring polymers are promising and would probably work great, (if you can get them with the correct specs) but I don't know if I am willing to bet $5K on them. If we could only find out what compound the Renesis is using...you can bet Mazda sweated the details on this.

Anyway, good luck on the rebuild, and post some electron micrographs of those O rings when you get a chance.

Kento

What about the recommendation from Evans that you need to run a water pump with a higher capacity/flow rate using their coolant? (per my previous post inquiry a while back in this thread) I notice that no one has said anything about this, and the Evans site says that due to the less thermally conductive nature of their coolant, cooling system flow should be increased by "theoretically approximately 20%". Although in the next breath, they say somewhat dubiously that it's "possible that improved thermal conductivity/transfer can result from the same [stock] flow rates".

Mr. Stock

I was just letting him have it for all the vulgarity, and condescension that he used when he responded to my posts. By the way, why aren't you chiding him? He is the first one to draw blood, so to speak.

But I think I made my point. And that is, what RonKMiller, or anyone, for that matter states as facts in a forum like this can be challenged and discussed, hopefully in a mature manner, and ,in the process, enlighten, educate and maybe entertain everyone.

Well, on that note, I am out of here.

johnchabin

iTrader: (2)

No, I can't find out who wrote it. I work in airsprings, and belts/hoses is a pretty big division.

The ECD is what causes the microcracks, not the acidity of the coolant. If that were the case, we'd see all of our hoses disintigrating from the inside-out.

Mr rx-7 tt

iTrader: (5)

Ron,
Don't waste your time with this little ignorant twit. He pops around and argues with everyone. I just ignore him...lol

Mr rx-7 tt

iTrader: (5)

Mr. Stock,
I don't want to hear about vulgarity or rude remarks it is kind of hypocritical of you. This is the e-mail Mr. Stock sent me:

"Hi Mr genius
Did I ruffle your feathers by proving that you are talking out of your *** in that thread: Attention! All 3rd Gen owners should read this?
I did know that your pride was so hurt!
Please accept my apologies - I won't pick on your frail little mind any more, *******!"


BTW Mr. Stock,
All you showed in that post was total ignorance...and don't send me any more childish vulgar e-mails Pal.

paw140

I think you may be drawing the wrong conclusions here. They are talking about processes such as physical aging (which makes the polymer brittle and subject to cracking), and solvent swelling. This is not ECD, at least from my understanding of it.

What's the moral of the story? Change your coolant every year, before it gets acidic to cause o-ring degradation. I also think that teflon encapsulated o-rings would be a good way to go, since for chemical and thermal stability, it doesn't get much better than teflon.

Just as an aside... I have no idea what butyl is (doesn't make sense), and epichlorohydrin is an extremely toxic and volatile chemical. I'm sure they really meant to say 'polyepichlorohydrin'.

RonKMiller

Bah Dah Bing! The end of the story...