[TR] Coolant Level Question

[terryrs at comcast.net]

I seem to remember being told that the coolant level in the radiator must be above the head on the engine.  Reason being, the head will not have coolant if it's lower than the radiator level.  This can cause a warped head.

This would seem to make sense when the engine is off.  But when the water pump is pushing water, or pulling it whatever, would it fill the head even if the radiator is just half full?

Important question because I seem to have a radiator leak that drops a quart every couple of days.  Engine operating temperature is normal, but is the reading accurate for the head?  

Will try emptying the coolant and soldering the radiator next week when I'm on vacation.  Can I drive it this week?

Terry Smith, '59 TR3A
New Hampshire