Pulley life?

When the belts are off, what is the best way to test the "health" of the pulley bearings? My engine makes a fairly loud whirring sound so I assume that one or more of my pulley bearings is on the fritz. Will I be able to spin the pulley freely with my hand if the bearings are out?

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This post was auto-generated based upon a question asked on our tech article page here: Pelican Technical Article: BMW Belt Replacement

[Wayne 962]

It can be a bit difficult to determine the condition of your pulleys when the engine is not running. Sometimes you can reach in with your hand and turn each pulley one of the time and sometimes one or more of the pulleys may not feel as smooth as the others. It's a bit of a subjective process and it's not an exact science. The typical way I use to determine if a pulleys becoming worn is to spray some lubricant or WD-40 on pulley when the engine is running. If the sound of the pulley changes and any squeaking or grinding noises go away then chances are that pulley is on its way out. Some of the pulleys are really easy to change so if you're concerned about which one is failing then it might be wise to just change them all at once it typically takes about 10 to 15 minutes per pulley.

- Wayne