re: "...would the harmonic ballancer stop making noise when nothings connected to it?..."

Probably. There ought to be enough friction remaining to cause it to slip ONLY if a load was on the outer ring while being driven by the inner ring; otherwise, the outer ring should follow silently.

But this is a big concern, so make sure of your "test" (the others gave good suggestions, e.g., chalk marking) results because if the harmonic balancer does separate, there are reports on this forum of the freed outer half chewing up the timing belt cover and in other cases the radiator.