Traffic Overheat

["Forlini,Franco" <fforlini@domain.elided>]

Hey Gang!!

My 74 spider doesn't seem to like traffic!!
Afetr an engine rebuild. My spider seemed to be running pretty cool.
In the last two or three weeks, now that the temperature here in Montreal
has gotten to summer levels, my car seems to run hot in traffic. If I don't
open up the heater vent, the car will read ~212 on the gauge.
As expected, keeping the heating on brings the temp down to a comfortabel
190.
Although that's not really ideal when it gets to 30 celsius outdoors.

I replaced the thermostat last year, rebuilt the head over the winter, had
the radiator tested and flushed, carefully filled the coolant system with
50-50 antifreeze to distilled water ratio. 

Oh, there are no bubbles in the expansion reservoir while the car is
running, so that removes one source.

I guess my question is what the heck could be causing this?? What is the
life span of a thermostat? Should I change it again? 


Thanks in Advance
Frank
74 spider......with a fever

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