Kawasaki Voyager XII - ZG1200-B6 air shock seperator what does it do?

I let a little air out of the valve in faring and oil came out.
so what does the seperator do ?
air line rums to it from air valve to seperatorthen 1 line runs to shock and a line connects both shocks.
I will be draining the 5 wt oil from the top portion of the shocks and refilling them per manual.
adding new o rings at the connections of hoses to shocks and back to seperator then to air valve.
going to presure test shocks while they are out

I do not see any oil leaking along the lines shocks do not hold air.
my hope is 5$ of o rings and proper level of oil in the shock solves that issue.
maybe new air valve 30$

I think the seperator 72$ is to prevent oil coming out the valve stem so it may also be part of the issue.

next step is a set of progressive shocks and eliminating the air system.
if the lines are bad thr price of 3 new lines at a 100$ each would be more that the progressive shocks
I would like to keep th air shocks if possible

 

drawing