Screeching noise from fan belt area...

[dfooch]

I have a 99 Expedition that has developed a loud screeching noise in the fan belt area of the engine compartment. I believe it is the bearings in either the A/C compressor, Alternator, or belt tensioner. It is very difficult to isolate where the noise is coming from while the vehicle is running. Does anyone have any cheap or easy trick to determinine exactly which component is causing the noise without me darn-near falling head first into the engine compartment?

PS: the noise continues with and without the A/C running.

Any assistance would be greatly appreciated.

[alloro]

Originally Posted by dfooch

the noise continues with and without the A/C running.

Then it's not the compressor.

Get a 5/8" wooden dowel, hold one end to your ear and touch various components with the other end. You will be able to isolate where the noise is loudest this way. Be careful not to let the other end hit any moving parts, you don't want that dowel jambed into your ear. It's best to touch the component with the dowel first so you know it's secure, then put your ear to it.

[sbclemens]

I would try using a remote starter to jump the starter relay. Bump the starter to turn the engine a revolution or less. You should be able to isolate the bad bearing.