I have a 1973 302 V8 with an updated 4bbl intake manifold and carb. I was hearing a knocking sound in the engine and took the valve cover off. The number 2 exhaust valve retaining rings were in shambles and the rocker was loose as well. I found and removed all the broken pieces and ordered a new valve seal and retaining clips. I was able to compress the spring with a tool and seat the new clips however I am unsure if I got them on the the lip of the valve shaft but they held so I assume that they caught. I checked the pushrod and isn't bent and put the rocker assembly back on the way I took it off. There was a little play in the rocker arm but my dad manually turned the engine and as it cycled through the stroke it tightened. I put the valve cover back on and turned the engine over but was hearing a clunk clunk and just all sorts of rough noise coming from the passenger side ( the side I was working on.) Im wondering what the heck is the problem. I think it might be because that cylinder wasn't being used for so long that there is just crud in there? I removed the spark plug wire and tried again but the same noise came. I didn't attempt to start it further. Is the timing off now that there is another valve in play? Could I not have set the lash correctly on the valve stem? The spring didn't shoot off lol although it did hit me in the junk when I had it in the spring compressor. Sorry lol if these are basic questions. Anybody got any advice?