Three things to check. Water pump, water pump, and water pump. I can't tell you how many of these I have changed in my shop. They have plastic impellers that get brittle and shatter, leaving a shaft that turns, but turns nothing. No flow, big overheat problem. I bought my Contour because the people thought the cylinder heads were out. It started and ran well, so I knew it was the water pump. Don't forget to take the hoses off and flush the pieces out, then flush or refill with fresh coolant.
