A/C Noise

So I took my 91 classic on a 12 hour trip to South FL last month, A/C worked fine, but unfortunately i had to replace a alternator because i got a new radio installed and the guy shorted my alternator. Anyway as i was leaving to drive back, my A/C which i always have on high (summers in Alabama are worst than the Atacama), made a loud hum noise and blew out what seemed to be dirt and leave particles from all the vents, now it still blows cold air, but it makes a very loud humming noise, which can be heard from the outside as well. Now the noise is usually heard on the last two settings, that is low max and hi max, but you cant really hear it on low-low or hi-low. It seems to be comming from the passengers side. I have been scouring the net for info, but cant find anything, so i tried here, since you guys seems to have all the answers.
Thanks in advance folks, and i am happy to now be apart of this terrific community!

That's your blower motor crapping out on you. Sounds like the bearing is shot. Part should be no more than $50 I would think. Best to get a new fan "blade" for it as well. Sounds like it was plugged up with stuff pretty good.

So I took my 91 classic on a 12 hour trip to South FL last month, A/C worked fine, but unfortunately i had to replace a alternator because i got a new radio installed and the guy shorted my alternator. Anyway as i was leaving to drive back, my A/C which i always have on high (summers in Alabama are worst than the Atacama), made a loud hum noise and blew out what seemed to be dirt and leave particles from all the vents, now it still blows cold air, but it makes a very loud humming noise, which can be heard from the outside as well. Now the noise is usually heard on the last two settings, that is low max and hi max, but you cant really hear it on low-low or hi-low. It seems to be comming from the passengers side. I have been scouring the net for info, but cant find anything, so i tried here, since you guys seems to have all the answers.
Thanks in advance folks, and i am happy to now be apart of this terrific community!

it can be the blower bushings worn or dry causing the noise..

removal of the blower motor and cleaning the fan if dirty is worth a try..

somehow an acorn got into my fan and I got a rumble noise at the higher speeds..if it makes noises at all speeds and the blower does not blow much at the lower speeds usually that is caused by the bushings needing lube..or worn ...

That's your blower motor crapping out on you. Sounds like the bearing is shot. Part should be no more than $50 I would think. Best to get a new fan "blade" for it as well. Sounds like it was plugged up with stuff pretty good.

Awesome, I am going to pick up a Hayens book so i can find out how to get to it. My Advance should have the motor and blade, going over there now to see if i can fix it today. This 100+ weather is horrible.

So I was able to get to the motor, after much work, turns out, a dead lizard was stuck in there, along with some junk and droppings of some sort. Cleared it out, A/C works fine now.
Thanks for the help guys!

So I was able to get to the motor, after much work, turns out, a dead lizard was stuck in there, along with some junk and droppings of some sort. Cleared it out, A/C works fine now.
Thanks for the help guys!Ewww :puke: