Good afternoon all,

I had a coolant leak on the small hose that goes from
the engine to the firewall/heater core, the upper of the
two heater core hoses. I replace the small hose this
morning and found dark sludge at that hose's connection
to the firewall.
In the overflow tank there was clear water that I had been
adding since the leak, in that water is small plastic/rubber
particles from the hear core hose that was falling apart.
I wanted to check my thermostat to make sure it was not
rusted shut. I removed the thermostat housing and immediatly
remembered that I had removed the thermostat a couple of
years past, since I live in NM I never saw the need for one.
The liquid that came out of the thermostat housing was
green/coolant. Shouldn't the overflow tank also have green/coolant?
If the overflow tank does not circulate it's fluid how am I supposed to flush
the system if I can't get the radiator flush into the radiator?
And does the coolant circulate into the overflow tank?

Thanks in advance,
Joseph in NM