Carver Owners Forum

I keep seeing folks refer to "corrosion inhibitors" when referring to the various concentrations of propylene glycol and even saying that some of the higher freeze points have more.

I DO NOT believe this is the case. I researched many of the various winterizing solutions and none of the prop glycol products had ANYTHING except prop glycol and water. The lower freeze points have a higher concentration of prop glycol but that's about it. If they are "non toxic" they don't have any "corrosion inhibitors" added in. Just putting in prop glycol by itself IS a "corrosion inhibitor" because you're displacing the air or pure water that would be up against your metal.

This does **not** apply to some automotive prop glycol products, because they are formulated for a different use. They are also likely *NOT* completely "non-toxic", but significantly less toxic than the old green antifreeze, especially for pets.

Ask for the MSDS sheets for the products and you can see for yourself.


(the alcohol-based products ARE somewhat 'toxic' (corrosive) to ANY system that contains metals)

OK - found the bottle. It is now referred to as CAMCO Ban Frost 2000. It used to be called "Extreme". It is Poly-Glycol, with corrosion inhibitors and is Bio-degradable. 1 Gallon of product, added to 2 gallons of water provides protection to -50F. Talked with a very good marine mechanic and he endorsed the product. Hope this helps! er

At $16/gal, it's 50% more expensive than the WM -100, and it's the same stuff.

Well that is good news for everybody. Good catch! er