What is causeing this knock? Video included inside.

[Trippin]

Drain the oil and run it through a paint strainer. See if there is any bearing material present. If there is.....it's a rod.

If no bearing material is there then...........

[tirekillinss]

sounds like a bearing, i agree with chuck L, had it's tongue out to many times.......

[batesyellow01]

I have heard that sound before. Not an LS1 but my first car a buick skylark.

[batesyellow01]

I have heard that sound before. Not an LS1 but my first car a buick skylark.Was doing the same thing ,reaching under hood reveing up the throttle and all hell broke loose.....Rod came right through the side of the block!!Lost a pizza shaped chunk of block three inches wide at the bottom.Hey I figured out what it was though Like the others say it sounds too deep to be valvetrain.This turned out to be my first engine removal and install, I dropeed an Olds. 455 in with a 400 tranny, built up the front to handle the new weight.That was back in 84. oops, sorry I rambled on

[Wingnut87]

I think I started a new thread and forgot to update this one. I pulled the engine and found that the first rod bearing was spun and had a noticable play. FYI, I was able to diagnose the cylinder by pulling plug wires and listening for the difference.

[joecar]

Here is the thread with Tom's update: showthread.php?t=3238

Post #19 has a link to pics.