Finding the scream...
 

Hi again! So my '94 2500 ~500K is running like a top, but I have a problem looming... I have a screaming bearing (still high pitched, but getting louder) on the front of my cummins, and am having trouble finding the culprit. I have tried using the ear to pry bar to component tecnique, and therefore don't think the squealer is alternator, waterpump, or power steering... However the scream is there, and I can't determine where. I have thought about getting a decibel meter and holding it around the components to see where it is loudest, but don't really want to make the investment. Can I do the same type of thing with a section of hose? Any other suggestions? I plan on removing the belt and starting it up this weekend to verify that it is a belt driven component. Any suggestions would be greatly appreciated!
Thanks!
Tim

Hey Ginger,
The only fool proof way to diagnose a squeal like that is to remove the belt. Spin each component over by hand and you will very quickly find out who's to blame. Whoever doesn't spin smooth is the culprit. Idler, tensioner and alternator are among the most common. The prybar trick sometimes works but it takes practice, especially at the front of the engine where there's a lot of noise makers.

I use a spray bottle with water to find screaming bearings.
With the engine running and screaming just spray water on the bearing areas, scream will stop for a second when the water hits it.