I just got my head back on and I'm adjusting the rockers... Well once I get them all tightened down and go back to check them, I can push down right above the pushrod and it will push the pushrod down a little bit then come back up... Kinda feels like I'm pushing on a spring. Whats wrong here and how can I fix it? I dont really know of any other way to explain it so sorry if it sounds confusing.