Thanks for straightening me out on the bright links. Could you tell me what binding would feel like if I did have a piston hitting a valve. I'm getting resistance at certain spots that feels like compression (the spark plugs are all out), there's no noise, and it's fairly easy to continue the rotation. If a piston was hitting a valve, would I even be able to continue the rotation by hand? I'm grasping the crank pulley and turning it clockwise.