Busted hose that runs from the radiator to the overflow tank, replaced the hose and went to start the engine there was a very loud scrapping.

The hose that runs from the radiator to the overflow tank had a leak. We bought a new one and replaced it. Very easy to do. 2 clamps didn't have to move anything, to get to it. Once we replaced the hose and went to start the engine there was a very loud scrapping noise, like metal on metal. I turned it off immediately. What could have happened? I am a senior citizen with no extra money for car repair, please tell me it's something easy to fix or maybe I could do myself