At 11:28 PM 6/8/2011, ron johnson wrote:
>1. Is it required to bleed the system after replacing the
>thermostat? Not much fluid was released and the temp seemed to
>behave normally afterward.

No.  I'd run it for a few minutes with the valve on the top of the
thermostat housing open.  Keep topping up the overflow after every
overnight cooldown until the level quits dropping.  If anything
Dennis Haynes says disagrees with me, listen to him.

>2. Is it normal for the Reservoir to be full AND under pressure
>(when warm) while the Overflow tank is empty?

Certainly, except that the overflow tank should never be empty.

>3. How does the blue cap on top of the Reservoir work? Is it
>supposed to release coolant to the Overflow tank or suck coolant in
>from the Overflow tank?

The cap has two valves in it.  The outgoing valve opens around 13 psi
and allows coolant or bubbles to bleed off into the overflow tank
when the system is hot.  Any time the system comes up to temperature
I'd expect it to spit a little into the overflow bottle.

The incoming valve works on very much lighter pressure, and allows
the system to suck coolant back in from the overflow when it cools
down.   There are Min and Max marks on the overflow bottle for where
the level should be maintained when the system is cold.  If your
system has a slow leak you can fill the overflow bottle almost to the
lip without causing a problem; this will give you a little more
reserve capacity.  Remember that the system only pulls coolant back
from that tank while it's cooling down.

Yours,
David