Re: the mysterious leaking coolant

["DON SCOTT" <rowdon@sonoma-county.org>]

I think you are consuming coolant internally.  There is a
tool which attaches to the radiator in place of the cap, and
then you pump the device to create pressure.  You can then
try to trace where coolant (or pressure) is disappearing.  
 
Another way to see if you're losing coolant internally is
(if my memory is correct) to drive to a smog station and
have have the sniffer device placed in the tailpipe.