All the hose connections to the radiator
No circulation in the cooling system
How do you figure? Is it running hot? No heat coming from the heater? You open the cap and just look at it?
Water pump thermostat fine possible hose leak
OK, look for wet spots under the car pay attention to its location, look under the hood for wet spots, hoses & radiator, best time to do this is after the car has run for a bit, park it and look under the hood for leaks. Let the car sit for awhile, see if any fluid on the ground. If you having trouble locating a leak, bring it to a shop who can pressure test the system, a trained eye can find a lead fairly quickly.
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