I have an intermittent squeal with varying intensity. Worse on humid mornings. Changed the belt as the dealer said it was glazed. Made it worse. Sounds like a cheap bearing to me, but don't know why it would be intermittent. Any thoughts??

 

Sounds like your describing a loose belt. Maybe the the pulley that applies the tension is not applying the proper tension. Check to see how much flex you have when you push down on your belt, should be very little, maybe a half inch max.

 

Try listening for a bad idler bearing with an automotive stethoscope, and make sure the tensioner isn't weak which would give you the previously mentioned loose belt. If the idler bearings and tensioner prove to be good, consider this:

What's your climate like?

Sometimes pulleys will rust and make noise, especially the smooth ones. I don't fully understand this, as there are plenty of vehicles on the road with rusty pulleys and quiet belts, but sometimes you run into a perfect storm where the squealing is persistent even with a new belt.

I have quieted down several problematic belt noise problems by polishing the rust off of the pulleys.

 

Just a follow up. Left my truck at the dealer Tues night for 8 am appt wed. They called me that afternoon and asked how to make it produce the noise. I told them to drive it, rev it up, let it idle, try it cold. It isn't that hard. The truck would make the noise for me all the time. Pick the thing up at 10 pm after they closed at 5.
Work order stated "unable to replicate noise". I started the truck to come home (25 mile trip) and there it was. Just had to get rpms up to 2500 or so. There was a light on so I knocked on the door til the tech came out. Demo'd the noise for him. He said that's not right and to bring it back Friday and he would tell the service mgr that I wasn't making things up.

Today they had to get the stethoscope out, but it turned out to be the water pump.

It often seems that incompetence follows me where ever I go

 

I am a Field Engineer and travel to customer sites to repair equipment.

I once sat by a machine for 2 days waiting to hear a squeal that a customer was having all the time on a machine and it never made a noise once, no matter how they tried to run it. They even put extra work on it since it happened under long runs. Eventually it did make the noise when I was fixing it a week later.

I hear your frustration in trying to get it fixed. Sometimes you have to wonder if these things are sentient and are trying to play jokes on you.