Did you get the hose clamps tight? Did you puncture a hole in the bottom of the radiator? Did you get the petcock closed all the way? You didn't overtighten the petcock at the bottom of the rad did you? Is your water pump good? Did you put thermostat in the right way?????????????
is coolant leaking from engine?or is it leaking from water pump and running down engine and appears to leak from engine
Running it while leaking can cause it to overheat repeatedly, which can cause thermostat damage , along with other problems.
Radiator fan inoperative, thermostat stuck closed, coolant low, radiator restriction, etc.
First you need to run the engine until the thermostat opens, you will see the water running through the radiator. the coolant will go down into the radiator You need to continue to add coolant until you don't see anymore air coming up, or coolant go down into the radiator maybe three times that the thermostat opens. When you have got most of the air out you will see the water running inside of the radiator then stop when the thermostat closes. Cycle it two or three times to be sure.
I would check the hoses leading into your radiator, and also the overflow for antifreeze. If that is not the problem, it could be your heater core. Your heater core might be leaking, you might have a hose leaking
possibly the water pump
Low coolant, failed water pump, thermostat, plugged radiator, inoperative radiator fan, head/head gasket.
Check your radiator and make sure it has coolant in it. Thermostat might also be stuck.
Thermostat needs to be replaced, it is not opening (most common). Is electric fan on radiator running normally from time to time?
generally, water pumps leak when defective but still pump water. could be thermostat, plugged radiator, loose belt, low coolant answer if pump is not leaking, get engine to running temp and remove radiator cap look in to see if water is circulating if water is circulating it is not the pump i would change thrmostat then check radiator cap
Thermostat stuck closed? Low coolant level? Radiator plugged or dirty? Water pump not working? Cooling fan not working? Defective radiator cap?
Can be a hole in the radiator or a problem with one or more of the hoses. A mechanic can run a pressure test to see where the problem(s) are located at.