there are like different grades of bio right? i am kina thinking that the pour point might be a sore spot with using it in a constant circ fuel system. seems to me it would like having an aboveground oil tank with a two line system and cause gelling at warmer temps than #1. i wonder if there is anything like a TigerLoop Combo,that can convert a recirc system to a point at the deareator.... allowing one line supply to it, from the tank and bring the other two lines to it to recirc continiously. google tiger loop combo oil deareator. you guys are savey ever heard of this?