Temperature question
 

I have a 66 GTO, 389 Tri-power bored over a little, basic cam, aluminum rad.

This is what happening.

When I take the car out for a drive the temperature gauge will start to creep up to about 210 (and a little more sometimes). It will then go back down to 190 (180 tonight with temps in the 60'S)and stay there.

Question:

Is my thermostat sticking?
Is there air in the Rad?

Do you guys have any ideas or had a similar problem?

Thanks,
FB66

If the temp only goes up and then drops when you first start the car there is an air pocket just below the thermostat. There is probably a very minor leak only when the engine is cold. If the problem occurs all the time then you may have a defective thermostat.

That is what I was thinking. When the car sits for the winter coolant is coming out and sitting on the water pump.
The high temperature only happens when I start it up when it is cold.
Thanks
FB66