[Chevelle-list] OT - F**D serpentine belt

[Karl Groves]

My daily driver is a 1992 F**D Bronco.

Recently, I've been hearing a ton of squeaking from the serpentine belt. I'm
wondering if it is the belt, the tensioner, or the fan clutch.  Here's why:

Initially, the squeak only happened when the engine was first started. Now
it is almost constant.

The squeak gets louder when the engine accelerates. At idle, it is (usually)
a quiet little "squeak squeak squeak", but taking off from a light or under
hard acceleration it is a deafening squealing noise.

When the squeaking stops, the fan is fully engaged, regardless of engine
speed, vehicle speed, or how long the engine has been running. If I'm
running 70mph, I can hear the fan roaring.

My semi-educated guess says that the fan clutch is bad, causing resistance.

Anyone out there have more experience with this, and can tell me how to more
definitively diagnose this?  I'd rather not just throw parts at the problem.

TIA

Karl