I found thgis info on a web site..

adding water to antifreeze actually increases the freeze-up and boil over protection provided. For example, a mix of 40% antifreeze and 60% water provides freeze-up protection down to -10°F and boil over protection up to 259°F. In comparison, a mix of 70% antifreeze and 30% water provides freeze-up protection down to -62°F and boil over protection up to 270°F. However, we do not recommend adding more than 70% antifreeze. This would limit the corrosion and freeze up protection and heat transfer capabilities of the antifreeze.

 

I have the same problem with my 500 HO. Thanks for all of the suggestions. Does anyone know where you can purchase Water Wetter?

 

There's a link in my post on the first page of this thread. Or just do an internet search.