[Fot] Hot Running 6

[Glenn Franco]

Hi
I just finished rebuilding a club members 74 TR6 that I had bored .060" 
over due to cylinder wall damage.
The owner had the radiator cleaned out, provided a new water pump, 
thermostat, temp sending unit and so on.
The car has a set of DGV Webers (downdraft) on it.
There are a couple of issues now with the engine I'm trying to sort out.

Engine runs on the warm side with the gauge between 1/2 and 3/4 some 
excursions to 3/4 when left idling for a _long_ time. When the engine is 
revved to 1,500-2,000 rpm it settles back down to 5/8ths on the gauge.

        * I suspected a faulty replacement temp sending unit and
          replaced it with one from my car and it brought the temp down
          slightly.
        * I also tried to burp the system by bleeding the air out at the
          sending unit but I can't seem to get it out. When I remove the
          sending unit there's just air.
        * Any better methods of getting air out of the head?? Doesn't
          seem to purge after thermal cycling the engine. New cap as well.
        * The replacement thermostat was a 165 deg. I suspect that it's
          higher than that. Can't measure actual coolant temp since I
          broke my Temp Tester.
        * My next step is to remove the thermostat.

Engine backfires through the carbs cold when when snapping the throttle 
when the chokes are off and not quite warmed up. Not a problem at 
operating temp/No backfires.

        * Distributor is the vacuum retard type and the vacuum line is
          disconnected.
        * Base timing set at ~1deg BTDC

Any Ideas?
Thanks in Advance
Glenn Franco
Too Many TR's they keep multiplying