Engine gets hung up

[of13swc]

Ok so while I have been doing body work and the engine has sat, for about a year. I re-wired it and when I finally startered it sounded like something bouncing around under the valve cover so I took look and everything seemed ok, with the covers off I tried and rotate the engine by hand. It goes to a point then seems to get hung up and will not move. I can rotate back and then go toward and it goes a little and does the same thing again. And suggestions? ? I have starated to break her down just seeing if you all had any ideas what the issue is?