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Lincoln aviator overheating

have a 2004 lincoln aviator that is running hot. i got the vehical from someone thay had changed the fan clutch and the thermostat but it still overheats i ran it for about 10 minutes at idle the fan is working fine but the temp gauge got close to the red so i turned it off the top radiator hose was very hot but the bottom rad hose was cold could it be the water pump or radiator?

Periods and capitalized letters would be nice.

I’m wondering if you might have a clogged radiator.

Maybe the thermostat is stuck closed.
It could also be that you have an air bubble in the system.

Regardless, don’t drive it like that.

You could try to burp the system to get rid of that airbubble by doing this: Put it under a slight incline (like a ramp) and add more coolant but leave the radiator cap off. Then start the car but keep your eye on the temperature to make sure it doesn’t overheat. Don’t ever let it overheat.
Rev it up and down a bit, watching to see if the coolant in the radiator goes down. Every time is does, add some coolant. You may see a large air bubble surface - much like a burp.

Remco is sort of tuoching on something I was thinking; did the previous owner properly refill the system after changing the thermostat? Burp the system as he described.

And yes, it is also possible that the radiator or water pump is bad. Both can be flow tested, and the radiator can be checked for plugged arteries with an infrared thermometer, which any shop should have.

It’s also possible that the inner liner in a radiator hose has collapsed and is restricting coolant flow.

There’s also a possibility that you have a headgasket breech. If you see bubbles streaming up through the coolant out the fill hole as you try to refill the system, you may want to do a cylinder pressure leakdown test.