Help on engine running hot...Can water pumps be checked??

Working on a 1992 Chevy Lumina APV. 3.1 L engine
The engine was experiencing several problems which have been repaired....but still running hot (not
overheating, just running hotter than normal).
Engine Temperature is 207.3 degrees (OBD1 tester). Electric Fan does cycle on and off. A radiator thermometer shows antifree temperature to be around 210 or so.
But, with the engine running and at 200 plus degrees, the system should be pressurized...but it is not. I can remove the radiator cap without having the coolent spurt all over. And the upper and lower radiator hoses...are hot but can easily be collapsed.
When thermostat opens and water begins to flow I get even heat over the surface of the radiator.
Cooling System Tester showed the cooling system holding 15 pounds pressure steady for over 30 minutes without losing anything. Also no leaks, or signs of leaks. Radiator Cap tested okay using tester but I swapped in a new one anyway. No change
The water pump was replaced about a year ago. Thermostat was replaced (tested before replacement). Radiator is full of coolent. (about a 50% mixture using an antifreeze tester.
Is the system failing to pressurize during operation indicative of a failing water pump??? Water pump is not leaking. No bearing noise (far as i can tell).
Is the troubleshooting technique okay....what am I overlooking ???
Thanks in advance for your help.
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You might consider a general degradation of cooling system effiency from time and mileage, rust and scale build up for example, my 3800 Lumina runs at 200 will not build up any real pressure without about 220 on the scanner.

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Thanks Shep.... your suggestion might be part of what is actually happening...
I just pulled the thermostat out.... engine runs in a range of 140 to 175 degree's depending upon speed of travel, stuck at a light or stop and go traffic. The engine did not pass 175 degrees even once. I also tested the thermostat it opened at 195 degrees (according to spec) and the opening looked about normal compared to another thermostat (used as a control).
I might swap out the water pump (although it's only a year old) as they are inexspensive and relatively easy to change out. If that doesn't make a difference, I'll try a 185 thermostat rather than the 195 (spec'd by the manual). I would prefer having less heat, rather than having the engine run hotter.
Thanks for your suggestion !!
Peter.

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Radyator grill might be clouged by dust, dirt mud etc. Try to wash it by pressurized water. I'm talking obut external dirt, not anything internal. good luck. If the fan couldnot flow enough air, it might run hotter.
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