I'm kinda in the same boat as you. I rebuilt the motor about 1 1/2 years ago. Within the past few weeks, there has been a knocking that I have not located yet. I might have to pull the oil pan to check the rod bearings <img src="/forums/images/graemlins/frown.gif" alt="" />. I pulled the valve cover and the timing chain seems ok. I haven't checked the valve's yet, just checked by hand the rockers and all. Haven't done the pull the plug wire yet with it running. With such a recent rebuild, I'm kinda worried. Maybe we've got the same problem. If I find anything out I'll post it.