squeak or sqealing noise under the hood

[55vicky]

First time poster as I only got my '79 Heritage a couple of months ago.
When I got the car there was a squeal like a bad belt would make so I changed all three belts. Still squeals. Checked the tightness again not trying to get them too tight, and it still squeals. Sprayed WD-40 around the bearings hoping it would seep into somewhere and quiet the noise, to no avail. Somebody said the alternator can sometimes make that squealing sound so I bought a new alternator. Still squeals. Stuck my head under the hood and gunned the engine by hand and it won't make the sound at all, it only does it under acceleration. Let off the gas and it goes away. There is no oil or anything on the pulleys, they are pretty clean. Belt dressing did no good. Has anyone ever had something like this before? I am stumped. Short of having someone ride under the hood while I drive it(which isn't going to happen) I can't figure out how to find where it's coming from. Any ideas?
Thanks in advance, Dave

[cdiedrick_79]

No idea really except for power steering. That is only a process of elimination guess though.
Chris Diedrick

[g_lower]

try some belt dressing or some paint on the pulley where the belt rides. or maybe they need to be alittle tighter. just some things to try let us know.