Without wishing to add to the confusion, does everything said so far about coolants apply also to the Silk?
I ask this because the age difference between Scotts and Silks suggests the probability of different metallurgy with different susceptibilities.
Use normal blue glycol based antifreeze , it’s that simple
I totally agree with Barrie, just use standard ethelene glycol based antifreeze, The Blue Stuff.
Ethylene Glycol is however toxic, that’s why you do not add it to wine as a sweetener — or let your dog drink it — but it has been proudly strutting its stuff since 1926, works and is cheap.
Propylene glycol is regarded as less toxic and therefore used in Switzerland.
Specialized coolants (Toyota et al), were developed for high temperature and high pressure applications, not really the average Scott scenario.
Regarding Evans Coolant, which has amazing claims made about it, is a neat mixture of glycols – no water, very expensive and is flammable, I looked into this some time ago for a special engine I was building, and rejected it.
Corrosion in the areas of a Scott engine that we cannot see is already a problem which can only get worse as the years go by. In theory the waterless nature of Evans Coolant should have significant benefits for us due to the absence of future corrosion. However I spoke to the Evans people a few months ago and was told that it was too viscous to circulate in a thermo-siphon cooling system. They did say that you could make it less gloopy by adding water – but I thought that rather cancelled out its key advantage…..
Regarding the red OAT versus blue IAT antifreeze debate, there is an interesting article on the Opie Oils website: https://www.opieoils.co.uk/pdfs/tech-articles/coolant-antifreeze.pdf
It is clearly stated that the red OAT antifreeze should not be used in cooling systems containing yellow metals. I admit to having used red antifreeze for the last few years but I have decided to drain and flush the bikes (red and blue antifreeze should not be mixed), and replace with the traditional blue stuff.
Going back to the corrosion issue, it is worth stressing that blue antifreeze should be changed every two years because the anti corrosion additives cease to be effective, and the anti corrosion aspect is key to the long term survival of the Scott engine. I believe that due to its toxicity, used antifreeze should be flushed down the loo to avoid danger to pets and children.
Thanks Barrie, Mike and Martin for your replies over the last couple of days.
From them, I take it that there is no reason to differentiate between the Silk and the Scott, as far as selecting a winter coolant is concerned, and have learned a good deal of other interesting stuff besides.
I read only today that a teaspoonful of ethylene glycol is fatal for a cat. It didn’t mention dogs, but of course they vary wildly in size…
So do teaspoons! 😆
I was thinking “British Standard Teaspoon” of course….
Just a simple question, where does monoethylene glycol which is green come in this discussion?
Anti freeze in the UK tends to be blue, the green coloured Anti freeze I have always associated with Japanese machinery ,but is the same animal 8)
There is also Propylene Glycol which seems to have the right properties and is non toxic, but it is much more expensive, and difficult to find.
More info here: https://www.performanceoilsltd.co.uk/antifreeze_engine_coolant.html