Trying to hunt down this issue im having with my 99 bravada i inherited.

There is a knock and a squeal neither sounding like they are internal but from the belt pulley area. The squeal is definitely not the belt its a metal on metal kind of squeal. The sound does not seem to be coming from top pulleys and i did replace the tensioner. It seems to be coming from around the water, power steering and crank pulleys but i cannot for the life of me tell which one. Not sure if its related but the AC only blows hot air and from what i am told it overheats making me lean towards the water pump.

My wife took a video with her phone that captures the sound pretty well. Keep in mind though i broke a spark plug cable and couldnt get it replaced tonight so its running on 5 cylinders otherwise it idles pretty well besides that awful noise.

https://www.youtube.com/watch?v=4ERw...ature=youtu.be

Any help would be greatly appreciated.

 

That sounds almost internal to me, like a rod knock. However, it could be a really loose water pump shaft. If you take the belt off and start it does the noise go away?

 

might also check the harmonic balancer. i had a SBC motor where the rubber seal came loose and the outer portion of the pulley was moving around. worth a check..

 

Noise is still there but the squeal is much much quieter. I started tearing things off the engine and noticed the water pump seal is shot and its been steadily leaking right into the back of the harmonic balancer. so im now trying to get a good look behind it to see whats up.

Im unsure on the knock but the squeal is definitely not internal. Its hard to capture the sound in a way that you could hear well.

 

Finally got around to popping off the timing chain cover and i seem to have found the issue. Looks like the crank snout is bent pretty bad. That would explain it. Now to decide if the things worth rebuilding or putting a new engine in.