I just had my exhaust taken off to fix a crack. This is on a 1999 civic ex D16Y8. I decided to look at the valves from outside the engine when I noticed something strange.

The right 3 cylinder's valves looked like this:






The left cylinder looked liked this:






Not sure If this is a seal leak or a valve that is slightly bent.

I recently replaced my timing belt about 6000 miles ago. Initially, when revved to about 2500rpm there seemed to be some knocking noise. I am not sure If I never noticed it before and it was a bearing or if it was from a valve due to a misaligned timing belt. The pulleys were already marked when I changed it and I never changed the position, just replaced the belt. I never changed it and the noise quiets after about 1 minute of warming up time. I am not sure if that could cause this to happen. Anyways back to the valves, just curious if anyone has any insights.