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nibs Member Posts: 503
So in winter time the discussions around antifreeze increase.
Arguments for and against, and suggested percentages, pro's and cons.
I read below that a poster used automotive antifreeze for 15?? years to good effect.
Automotive Antifreeze has improved over the years, it has to deal with various metals such as Aluminum heads, cast iron blocks, copper radiators and steel pump impellers, working under pretty severe conditions from well below freezing to above 212F.
Is there any real science regarding hydronic antifreeze solutions compared to auto?


  • GroundUp
    GroundUp Member Posts: 1,868
    Aside from the part that most automotive antifreezes are ethylene based and toxic? Silicates seem to play a big role in this as well as the lack of inhibitors in it. Any system I've ever been into that used automotive antifreeze was coated in a siliconized jelly, and it seems to always target the CI components like pump bodies and impellers for premature wear. Why it doesn't eat CI blocks and heads or leave that slime in an engine I don't know though.