1997 Volvo 850 - Chirps near belts

[xHeart]

Is it quiet now?

What was the culprit?

Last several starts, it did not chirp.
The replacement Volvo belt tensioner is sturdy -- idle, no shake or vibration as compared to the one i removed. The pulley was submersed with powder, same color at the belt.

I will post few pictures to show the wear on tensioner, and rust on pulley - original AUG 1996.

an observation -- The engine noise frequency would get several decibels louder few minutes after the start of engine. The chirp started recently, it would come right after the loudness began. Imagine increasing the bass, low range on your stereo. With this replacement I am not hearing the louness anymore. Keeping eyes and ears wide open for few more days to be certain.

Many thanks.

[cn90]

xHeart,

In the serp belt system, a bearing is inside:
- PS Pump (rarely a problem because it receives lubrication all the time)
- Alternator bearings
- Idler Pulley
- Tensioner pulley
- WP Pulley
- AC Compressor Pulley (bearing in pulley and another bearing inside the compressor).

For the most part, the offending parts are the idler and tensioner bearings like you said.

I found some random video from youtube, when a pulley bearing grease dries up, the balls in the bearing have no lubrication and will create this kind of noise...