The thing with the anti-freeze is this, it will not freeze HARD at -50.
You can't crack a block with slush, don't worry about it.
What antifreeze do you guys use to winterzize. I bought some of the pink Marine/RV antifreeze and ran it through the cooling system via a 5 gallon jug connected to the flusher. I thought I would test the antifreeze by placing a containter of it in the freezer to see if was actually good to -50. Not quite, started to freeze up in my freezer and it only gets to 0. I think I'm gonna be safe and order some -100 antifreeze. I live in IL and it is very likely it will be below zero a couple times this winter.
The thing with the anti-freeze is this, it will not freeze HARD at -50.
You can't crack a block with slush, don't worry about it.
Right at the end of a winterization I stick a jar under the exhaust and capture a couple ounces in a jar. I put it in the freezer and look for it to simply turn into a soupy slush. Just because it turns a little slushy is not a bad thing. Its when you see it get rock hard that it's a problem. It is also a much slower process for it to actually even start to slush which also prevents engine damage.
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