High pitched squeeling noise when blower is on

[benhogan]

So I press the defrost button and hear this high pitched squeeling noise. It goes away when I toggle the button off.
So I think it is either the blower fan (unlikely I think) or likely a/c belt slipping against a seizing a/c compressor clutch.

Is this the right diagnosis?

Also, one more observation. with the a/c off, I can hear a metal to metal sound.

I believe the a/c clutch is about to seize. So before I leave work today, I plan to cut the two fan belts turning the a/c compressor.

Belts are cheap anyway. I just want to make it home without incident.

What do you think?

[Chris W.]

Should be easy enough to tell whether it's the fan by putting the blower on without the AC compressor engaged. Squeeky fans are common. Lots cheaper than a compressor!

Rgds,
Chris W.
'95 E300D, 391K

[jay_bob]

Yes, hit the EC button then max fan speed.

Do this with the engine stopped and key in II to absolutely rule out the compressor making the noise.

[Zacharias]

A squeeling blower motor can be surprisingly loud under the hood.

[Walkenvol]

Originally Posted by Chris W.

Squeeky fans are common.

X2

[Dan Stokes]

I don't know on your car just how visible the A/C compressor is but if you can see it you should be able to see if it's freely rotating when engaged. But the more likely culprit is the blower motor - common in ALL cars!

Let us know what you find.

Dan