Humming Sound When Ac Is On

[1995ls400]

Hello all,

I recently had my water pump, belts and pulleys replaced in my car to remove a squealing sound in my engine.

well the squealing sound is gone after multiple trips to the delearship, but now when I turn my AC on, I hear a loud humming noise.

It even over powers my radio. I went to the dalership but they said it sounded normal. Now, I may not know anything about cars, but I know it is not normal. So I have come to the experts.

any ideas of what the humming sound is when the AC is cut on?

thanks

1995ls400

[gremio]

I'm having the same problem on my 91 LS.

Sound is driving me crazy...

[99lsguy]

95ls,

I'm stumped on this one...........

Can you look thru the little "glass window' and see if there are any "bubbles" or anything?

Also, check the tensioning of your serpentine belt. You had trouble with it (from dealer?), maybe they've got it TOO TIGHT so its wearing the pulley bearing too much