Anti Freeze too strong?

Halo

Halo

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Dear All
I changed the anti freeze and co**ed up. I miscalulated the volume needed and ended up with about 4.5 l of pure anti freeze (Halfords best red type) and 0.5 l water. The hydrometer read that the mix is good to - 37 C !
Is there any problem with over strength anti freeze in my Yanmar 3YM30 ?
Any thoughts appreciated
Martin
 
Don't think it will do any harm - let's face it, most vehicles in Siberia probably run on that concentration every winter. I suspect that the cooling effect will not be so strong - you may need to dilute it a bit before the hot weather next year.
 
My engine manual warns not to go over 50%.

It may well be the cooling effect that needs to be considered rather than the ultimate freezing point.

Can you drain, collect and use next year? If it were me I would stick to the recommendations of the manual,, and then you will never be left wondering.
 
Halo said:
Dear All
I changed the anti freeze and co**ed up. I miscalulated the volume needed and ended up with about 4.5 l of pure anti freeze (Halfords best red type) and 0.5 l water. The hydrometer read that the mix is good to - 37 C !
Is there any problem with over strength anti freeze in my Yanmar 3YM30 ?
Any thoughts appreciated
Martin
Click to expand...

Bizarrely, neat antifreeze has a higher freezing point than 50/50 mix. Though what that is I've no idea! I believe 50/50 is the optimum.
You may also find that the heat capacity of your mixture is low which may cause overheating. Water has a surprisingly high capacity for its mass.
 
Ruffles said:
Bizarrely, neat antifreeze has a higher freezing point than 50/50 mix. Though what that is I've no idea! I believe 50/50 is the optimum.
You may also find that the heat capacity of your mixture is low which may cause overheating. Water has a surprisingly high capacity for its mass.
Click to expand...

A somewhat simplified explanation is that they form a eutectic at about 64% with a freezing point in the region of -65C.

In fact rather more complex because ethylene glycol forms a hydrate resulting in a eutectic, with a freezing point of about -50, between the EG hydrate and water and another between the hydrate and pure EG

Phase diagram explains all:

H2OEGlycEutectic1.gif


To the OP . The above means that your mixture should be Ok down to about -30C but the loss in heat capacity may be significant
 
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VicS is quite correct that Ethylene Glycol is not as good a conductor of heat as pure water. When used in cold water cooling systems that operate close or sometimes below freezing the fall of in machine capacity of the cooling plant above 10% dilution is remarkable.

I can obtain from my work technical library a typical manufacturers graph for reducing capacity as the strength and hence minimum operating temperature increases with % of glycol added.

So your risk is overheating the engine.

I would simply draw off say 40-50% of the qty, keep in a spare container then add back the same amount of water. As long as you are above 25% final dilution you will be just fine.
 
Glycol is indeed a very poor conductor of heat, and the reason we fill Webasto wet heating systems with 15 to 25% max, Eber say 50% (a throwback from engine pre heater days) but that causes awful cycling of heaters, when this is reprted I just drop the concentration and it always cures the issue thus proving the theory. Personally I like pure water and inhibitor with a frost stat but that is not on for a motor that has no other frost protection.
 
GrahamM376 said:
I have some Alphi 11 left over from anti-freezing our central heating system and have wondered if suitable for engines, it's propane-1,2-dio.

http://www.tapoutlet.co.uk/media/ca...anti-freeze-61033-specifications-sheet-14.pdf
Click to expand...

Very possibly might be but with no information on the inhibitors and the possibility of cavitation erosion of cylinder liners in mind I think it would be inadvisable to risk it.

Propylene glycol is the non toxic alternative to ethylene glycol. Its used where toxicity of ethylene glycol is an issue but not yet widely in engine antifreeze.
 
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Some really good info so far - many thanks to you for saving me an overheating problem next season !!
If I am right then the "hydrometer" I am using ( a glass tube with a rubber ball to suck up the liquid and 6 coloured plastic discs which float to indicate freezing point) cannot really tell me how strong the mixture is. At present 5 discs float indicating -37C the 6th does not float and if it does then the reading is "unsafe" .
AM i right? Is there another easy way to determine the % mix ?
Thanks again
Martin
 
nigelmercier said:
Unless I'm reading it wrong, according to Vic's lovely phase diagram that means you have 50/50. Are you sure it was not the pre-diluted stuff?
Click to expand...

Nigel
I read Vics diagram and thought it could still be pure ethylene glycol - have I read it worongly ?
Martin
 
Halo said:
Some really good info so far - many thanks to you for saving me an overheating problem next season !!
If I am right then the "hydrometer" I am using ( a glass tube with a rubber ball to suck up the liquid and 6 coloured plastic discs which float to indicate freezing point) cannot really tell me how strong the mixture is. At present 5 discs float indicating -37C the 6th does not float and if it does then the reading is "unsafe" .
AM i right? Is there another easy way to determine the % mix ?
Thanks again
Martin
Click to expand...

nigelmercier said:
Unless I'm reading it wrong, according to Vic's lovely phase diagram that means you have 50/50. Are you sure it was not the pre-diluted stuff?
Click to expand...

Halo said:
Nigel
I read Vics diagram and thought it could still be pure ethylene glycol - have I read it worongly ?
Martin
Click to expand...

Id assume that if 5 discs indicate a safe mixture they are all on the LH part of the curve. The 6th must be a higher density, possibly on the RH section

Therefore I would deduce that if 5 discs indicate -37C the mixture is approx 50%.

Assuming its all fully mixed...... you have run the engine ? ....... its OK and you may have used a ready diluted solution or the system was not fully drained.

Run it some more if possible to ensure that it is fully mixed and test it again. If the right number of discs float its OK.... they measure density and therefore indirectly % EG, not the freezing point. That can only be deduced from the density by reference to published data or the phase diagram
 
Thanks Vic
I expect the system was not fully drained and will assume 50/50 unless she overheats next summer. I have a calorifier and the circuit is hard to drain and of unspecified volume. I had run the engine and been on a short blast round the bay before the latest measurement
cheers
Martin
 
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