OK I did a little research and what I found is that the system does need a fresh air source. There are two basic types of systems when it comes to a fresh air source. They are open and closed. An open system is one that draws air through a vented filler cap. Our typical setup. This works fine except when crankcase vapor becomes excessive and then is forced out of the breather. Hence the little puddles of
oil. The closed system draws (or expels) air from the air filter housing. So when the vapor volume is high, it is introduced back into the engine. No more little puddles.
Rick