So I recently did a valve job on my 4.3l 4x4 blazer. I actually had a machine shop do the valve job I just removed and replaced the heads.Ive been driving it everyday for 2 months now. Everything has been well. Until I drove to my moms, which is 40 miles from my house. I was around the corner and I noticed what I thought was a slight knock or click. I pulled over, checked the oil/ coolant. Everything was good but now my engine was noisy. Not too bad so I drove to my moms. I let it sit for 4 hrs then when I went to drive home I got to the stop sign and it stalled at idle. It wouldn't restart. I got a jump and it started after a few cranks. Now it was way way rough sounding and at idle it stalls. If I kept the rpm's up it ran, just sounded loud. At this point all the noises got louder and now I had a rattle and a whine. I left it there and got a ride home. What do you think? Has anyone seen this before. Click the link below for a video. Any help is appreciated.

video-2011-12-03-13-16-29.3gp - YouTube
or
http://www.youtube.com/watch?v=sgRLA90kwS8

 

I took the belt off to eliminate the possibility of pulleys seizing up and problem didn't go away. Next I drained the oil to check for metal. The oil was black but no metal found.