Good idea...dump the condenser! With the fan running all the time, you really shouldn't be running hotter than 190 at any time. The first few times I tried purging the cooling system of air, I forgot to open the heater valve...good catch Ron!
I never had luck filling my system from the heater hose T. Here's what consistently has worked for me:
1. Warm up motor to full operating temperature with the heater valve open
2. Turn off the motor
3. Relieve coolant system pressure at the radiator cap
4. Remove the bleed screw (see picture below)
5. Back fill they system using a funnel
This has worked for me even when the car was level.
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John G.
1979 Spider (Owned since 2000)
1971 124 Sport Spider (Owned since 2017)
1977 Spider (Sold 2017)
1979 Spider (Disposed of in 2017)
1979 Spider (Sold 2015)
1980 Spider (Sold in 2013)
1981 Spider (Sold in 1985)
2017 Spider (Owned since 2019)