Winter - Proper Antifreeze Mix

[Scotty Dive]

this is my first winter with my 2020D. I am holding off on the block heater for now....the previous onwer said he had no trouble starting her in sub freezing temperatures.

My real question is - when I flushed the coolant this sumemr I put a 50/50 mix in.....with that mix I never see 160 degrees on the temp gauge...is this mix also going to get me through freezing temp's? I assume it will as its what I use in all of my vehicles...but I would rather ask a stupid question then wake up to a cracked block.

 

[Egon]

50/50 is the correct mix ratio.

Straight water has a better heat conductance value than an anti freeze mix.

 

[Car Doc]

Yes 50/50 is correct (for most places) its -32 and 265 and keep one thing in mind AF mix even a weak one will probably not freeze solid they will slush up but wont cause freeze damage so what I am saying is you could see -40 or less and still be ok. :thumbsup:

 

[California]

And ... a lot of the complexity and confusion over antifreeze in a Yanmar is because the old thermosiphon (no water pump) models need a lean antifreeze mixture to circulate the coolant properly when hot. (YM1500, YM1700, etc). The theory here is pure water has the highest temperature differential between the block and the radiator, causing rapid circulation. Adding antifreeze lessens this differential and makes the cooling system less effective. I think the conventional wisdom for the thermosyphon models is you don't exceed 1/3 antifreeze unless needed for freeze protection.

As for the rest of the Yanmars with conventional cooling, ie have an ordinary water pump like an automobile, I think the standard automotive coolant recipe (50/50) is what's applicable.

Heck your YM2020 is so new it might even have a thermostat.