My upper radiator hose all of the sudden does not pressurize when the vehicle is hot, neither does the radiator (i can remove the cap anytime, hot or cold). So I pressure tested the system, it checked out holding 16psi forever if i left the gauge on. Bought a new stant radiator cap and pressure checked that, turned out to be around 14psi for the new cap. Put a new stant 195 degree thermostat in it. Ran the car without the cap on and the front end jacked up a foot to help with trapped air. Nothing helped and I am still without pressure. The car does not overheat according to the dash guage, warms up to normal temp right in the middle and stays there. Pulls fluid from the overflow tank after warm up too. I have heat that is very warm/hot out of the dash and defrost. Return hose to the radiator gets hot but no pressure, bottom hose feels cool with no pressure. I know there is some circulation as the car is not overheating but the top hose can be pinched without feeling anything running thru it. I am leaning toward the impellers being rotted off the water pump and not pushing fluid like they should. Any other suggestions before I tear the front end apart to change a water pump?