HI I OWN 2 SCAGS AND HERE IS THE PROBLEM WITH ONE OF THEM: 1. IT IS OVER HEATING 2. Hose going from the radiator to the thermostat builds a lot of pressure. ( it gets really hard / seems like it inflates ) 3. Hose going from the thermostat to the water pump builds a lot of pressure also. ( it gets really hard / seems like it inflates ) 4. Hose coming from the engine to the radiator builds up pressure also. ( it gets really hard / seems like it inflates ) 5. Hose coming from the radiator to the antifreeze reservoir pops out of the reservoir because of the pressure build up. I ALREADY TRIED THESE: 1. Change thermostat 2. Treated radiator with flush chem. Problem still remains. NOTE: The hose coming from the radiator to the antifreeze reservoir starts throwing air bubbles into the reservoir and when it gets really hot it pops out of the reservoir, I was told by dealer it is due to boiling antifreeze inside radiator which makes good sense to me. They told me since there is no circulation of antifreeze it might be a clogged radiator or water pump failure. Like I've said I've flushed the radiator and problems persists, any one knows how to test the water pump??? the radiator cap does not have to do anything with this??? thank you for taking the time of reading this and i hope to get a little help to resolve this problem.