Antifreeze color

Aug 22, 2017
1,609
Hunter 26.5 West Palm Beach
it matters little what material the containment system is made out of to either type. and it is the truth that the two type so antifreeze are NOT compatible with one another, although they WONT gel up if mixed,
There are more than just two colors of antifreeze/coolant out there. I know of yellow, orange, green, blue & red. I don't know if there may also be more that that.

A friend of mine had a very expensive repair bill from a Mercedes dealer, after loaning his car to a well-meaning relative who added the wrong coolant, so at least according to his mechanic, there is some combination of coolants that does plug up the cooling system. This was not a boat example, but some people do buy their boat antifreeze from the auto parts store, so I think that the example can be considered relevant.

The source indicated below, seems to state that certain coolants are incompatible with certain cooling system materials -
http://www.popularmechanics.com/cars/how-to/a91/1272436/
Quote from above link -
"The new organic acid antifreezes may be used only if the cooling system has an aluminum radiator (rather than copper-and-brass)."

My original information came from a conversation that I had, many years ago, with an engineer at a UAW plant in the Detroit area, where I was doing some technical consulting work.
 
Mar 20, 2012
3,983
Cal 34-III, MacGregor 25 Salem, Oregon
There are more than just two colors of antifreeze/coolant out there. I know of yellow, orange, green, blue & red. I don't know if there may also be more that that.

A friend of mine had a very expensive repair bill from a Mercedes dealer, after loaning his car to a well-meaning relative who added the wrong coolant, so at least according to his mechanic, there is some combination of coolants that does plug up the cooling system. This was not a boat example, but some people do buy their boat antifreeze from the auto parts store, so I think that the example can be considered relevant.

The source indicated below, seems to state that certain coolants are incompatible with certain cooling system materials -
http://www.popularmechanics.com/cars/how-to/a91/1272436/
Quote from above link -
"The new organic acid antifreezes may be used only if the cooling system has an aluminum radiator (rather than copper-and-brass)."

My original information came from a conversation that I had, many years ago, with an engineer at a UAW plant in the Detroit area, where I was doing some technical consulting work.
there are many different colors, as the engine manufactures use different colored dye, and it only creates confusion so that the consumer will buy the expensive coolant that is recommended by the engine manufacture....
but there are ONLY 3 types of coolant, (conventional, elc, universal) and only the 2 most common (conventional and elc) that are not compatible with one another... the universal type can safely be added to either system but is not as common on he market because people who dont use the green, go direct to the ELC that the manufactures say to use, because they think they HAVE to... the universal isnt getting much market share so its not as common... yet.
 
Mar 26, 2011
3,401
Corsair F-24 MK I Deale, MD
Lots of misinformation.

In fact, the coolant needs to be changed every1-2 years, regardless of the type, because contaminatoin with as little as 25 ppm chloride (that's only 1 part per thousand contamination with seawater) renders it out of ASTM specification. Though not all builders have picked up on this, if you read the recommendations for marine vs. generator for Yanmar, for example, there will be two different change intervals. The marine interval is short because seawater contamination in the cooler is common.

As for the talk of colors and the chemistry they imply, that is nearly all unreliable. There is no ASTM standard for colors, and conventional, OAT, and hybrids are available in all colors. Unless you know what brand and type it was, just change it (flush not required). I formulated AF for decades, and I know how many exceptions there are to the color "rules."
 
Aug 22, 2017
1,609
Hunter 26.5 West Palm Beach
there are many different colors, as the engine manufactures use different colored dye, and it only creates confusion so that the consumer will buy the expensive coolant that is recommended by the engine manufacture....
but there are ONLY 3 types of coolant...
According to Amsoil, the following types of antifreeze are currently produced - IAT, OAT, HOAT, NOAT, NMOAT, & POAT. That totals up to more than 3 types.

http://www.engine-performance-onlin...l-antifreeze/engine-coolant-antifreeze-types/

I also seem to remember that in the distant past, before the days of “permanent” antifreeze, there was also blue methanol antifreeze.
 
Mar 20, 2012
3,983
Cal 34-III, MacGregor 25 Salem, Oregon
According to Amsoil, the following types of antifreeze are currently produced - IAT, OAT, HOAT, NOAT, NMOAT, & POAT. That totals up to more than 3 types.

http://www.engine-performance-onlin...l-antifreeze/engine-coolant-antifreeze-types/

I also seem to remember that in the distant past, before the days of “permanent” antifreeze, there was also blue methanol antifreeze.
the methanol antifreeze is still a thing, but not for automotive use. its still used in some industrial applications.

if one wants to call it a different type every time an ingredient is changed, then Amsoil is right.
but there are only 3 basic formulations of antifreeze coolant that one needs to concern themselves with... what they add or dont add, as additives to them, or whether its considered organic, non organic or a petroleum based product makes little difference in how or why it works, but only in what it can or cant be mixed with.... in addition, some coolants have NO antifreeze properties, but in the context of the thread, we are discussing antifreeze coolants for consumer use in their engines.

for those that have a tough time understanding what all the different colors mean, it would undoubtedly be better to say, there are ONLY 3 different categories of antifreeze coolant for automotive/commercial use, and ALL the different formulations and colors one can find produced by the numerous manufactures, fall within one of these three groups....
 
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rukidn

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Apr 23, 2012
160
Catalina 310 258 Sandusky, OH
Lisa,

Back to your original concern. I suggest the well under the engine be cleaned up completely so you can see any new leaks. I am a little doubtful that the coolant came from the tank overflow unless recently topped off and overfilled. The heat exchanger (HX) outer case will leak engine coolant/AF if compromised, so it is important to ensure the HX and also the hoses are sound. (We had a broken HX bracket wear a hole and we overheated before we knew it. Radiator shop fixed the hole, cleaned and pressure tested for only ~$60).

Regardless of type/color, I've never had coolant/AF let me down; only the hoses, water pump, heat exchanger, etc. BTW, I use green and it's brown/reddish after 2 years. I wouldn't worry too much about rust. As long as the system is kept full with minimal or no air pockets, rust will be inconsequential.

All the best with your purchase. You'll love the 310. /Ed
 

KZW

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May 17, 2014
831
Catalina 310 #307 Bluewater Bay, FL
At the risk of highjacking this thread a bit, does the hole under the coolant manifold cap (where the hose from the overflow tank to the manifold arrives) go straight through, or does it wiggle around somewhere?
I can fill the overflow tank, remove the cap from the manifold, and no fluid flows. I've removed the fitting where the hose connects to the manifold. The hole in the fitting is just fine. There is a hole on the inside lip of the manifold, but it doesn't go through all the way to were the fitting connects.
 

jviss

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Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
At the risk of highjacking this thread a bit, does the hole under the coolant manifold cap (where the hose from the overflow tank to the manifold arrives) go straight through, or does it wiggle around somewhere?
I can fill the overflow tank, remove the cap from the manifold, and no fluid flows. I've removed the fitting where the hose connects to the manifold. The hole in the fitting is just fine. There is a hole on the inside lip of the manifold, but it doesn't go through all the way to were the fitting connects.
The way this works is that the radiator cap has two valves, a pressure valve and a vacuum valve. It has two seals, the outer cap seal, and the inner cap seal. It The outlet for the coolant recovery tank is between the two seals. Assume the cooling system is properly bled, and there is no air in it, or very little. When the engine heats up the coolant expands, and the excess causes a pressure increase; the pressure cap bleeds the excess pressure, by allowing coolant past the pressure valve, which then flows into the overflow tank. When the engine cools the coolant in the engine contracts. When this contraction results in a cooling system pressure below ambient pressure, coolant is sucked back into the cooling system from the overflow tank through the vacuum valve.

You should be able to see the hole for the overflow tube when you take off the radiator cap.
 
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CraigS

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Jun 2, 2004
36
Catalina 310 Fort Walton Beach, FL
KZW That hole does go straight thru but periodically gets clogged. I then take a small gauge stiff wire and poke it thru from the cap end until fluid flows freely from the expansion tank. I am now in the habit of checking it once a year.
 

KZW

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May 17, 2014
831
Catalina 310 #307 Bluewater Bay, FL
"You should be able to see the hole for the overflow tube when you take off the radiator cap."

I can see the hole with the cap removed.
I can remove the cap, with the overflow tank full, and the tank doesn't drain into the manifold. I think it should. I've removed the fitting from the hose to the manifold, it is clear. I've tried to push a wire through the hole; tried from each side. It hits something solid. Measuring how far I can push the wire, it appears to be the outside wall of the cap structure.

I'm considering drilling all the way through, but really don't want to mess things up.
 
Jan 22, 2008
8,050
Beneteau 323 Annapolis MD
I have heard before that the hole where the overflow hose is connected, is not punched through, or maybe soldered closed accidently.. Like on garbage disposals at home- the dishwasher inlet has to be punched out (like a metal electric box). Took a while to figure that one out.
 

KZW

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May 17, 2014
831
Catalina 310 #307 Bluewater Bay, FL
So, is the consensus to drill straight through?
 

jviss

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Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
Don't drill anything yet! Take the hose off the coolant recovery tank, and remove the pressure cap from the manifold. Blow into the hose. What happens?
 

KZW

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May 17, 2014
831
Catalina 310 #307 Bluewater Bay, FL
Nothing happens. No air flows. Tried that when I bought the boat three years ago.

No matter how much you empty the overflow tank and hose, there is always some coolant left. Not an epicurean delight!!!
 

jviss

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Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
I don't want to be responsible for any damage, but you might want to drill it. Maybe check, look closely, to see if it's a blob of solder blocking it.
 
Jun 22, 2017
4
Hunter Hunter Kemah,TX
Can anyone tell me what the pressure rating of the heat exchanger tank cap (radiator cap) on a Yanmar 3YM20 should be? It has some kind of gunk on the rubber and the pressure rating is not marked on the cap.
 
Jun 22, 2017
4
Hunter Hunter Kemah,TX
That would be a great place for it but I don't see it there or in the cooling system section. About 7 pounds should be OK but just thought I'd ask.
 

jviss

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Feb 5, 2004
6,745
Tartan 3800 20 Westport, MA
That would be a great place for it but I don't see it there or in the cooling system section. About 7 pounds should be OK but just thought I'd ask.
I was going to say 14 psi, as this is a common automotive and marine coolant pressure. I searched, and found this, on p. 181 of the Yanmar 3YM30 Sevice Manual:
The middle of 82 to 109 kPa is 96. Converting form there, and viola!