After driving a few miles I started to hear a ticking noise. I opened up the valve covers and noticed that one of the rocker arms was loose and some of the pushrods were spining easily and so I re-adjusted all the rocker arms. Now the engine turns but will not fire up and it sounds like something is stuck. I loosed up the rocker arms and re-adjusted them but still the engine will not start. Is it possible that I over tightened the rocker arms causing some of the lifters to get stuck in the lifter bores?