Well I finally got my Classic Air AC on (questions feel free to ask). Moved all my belts around.
Now I get a squeal at about 4K rpm.

It is the Unisteer Power steering pump belt going around the water pump and the crank.
I checked and rechecked the best I could the alignment of the pulleys, Tightened the tension, and even changed the belt.
After changing the belt, the squeal stopped for about 30 minutes of driving. Then it started up again

Does anyone have a good way to align pulleys? I have checked using a metal dowel, a straight edge etc. It looks good. But I could be off in angle.
Anyone use a laser alignment system for conventional pulleys?
Also, I have billet aluminum Pulleys.

Thanks

Here is a Gates Belt Manual on Pulley Alignment:

Gates Belt Allignment Manual link

There are also lots of YouTube videos on Laser Allignment:

https://www.google.com/search?as_q=YouTu...&gws_rd=ssl

I never had access to a Laser Alignment Tool, so I just used Straight Edges, Yardsticks, etc.

Could it be glazing on the belt or a pulley?

Could be a fan/fan clutch issue also. A heavy fan and tight (or no) clutch can load the belt up. What type of fan clutch? The fan clutch should start slipping at high RPM and limit load on the belt.

Fan clutch has less than 1000 miles on it. It just started when I changed belt positions. But I am sure I knocked the fan clutch around changing belts... Interesting...
could the belt be too tight? I am going to check alignment again...and again...

Did some more thinking...
The fan clutch maybe something to look at. Before there were 2 belts around the fan. Now due to adding the AC Compressor I have only one. Maybe the big fan clutch is putting too much resistance on the belt.

What is the best fan clutch to replace mine. Is there a way to test a fan clutch?

is it squealing on the new pulleys?

Through the aluminum pulleys in the scrap pile. there's your problem.

There are not great tests for the fan clutch but a few that can be done. First is easy - check for slop in the bearings. Another, is when cold and engine off, it should spin without too much resistance after a few turns to loosen it up.

As far as clutches, the "loosest" was the MP viscous kit which does not seem to be available any more.

A "heavy duty" clutch is made for the big 7 blade fan. It will tend to "lock up" more, especially with a lighter fan. I am thinking the "heavy duty" clutch probably wants 2 belts.

I have recently used a Bouchillon thermal clutch with their 6 blade fan to to replace the MP unit and it works well with my "single belt" setup for the fan.

I have a 7 blade fan on I believe a heavy duty fan clutch with one belt going around an aluminum bullet pulley. Maybe the issue...
I spinned the fan, it goes about 1/4 turn. Must be an HD?

With a 7 blade fan it should be the HD type clutch. Great for max low speed cooling but puts more load and inertia on the drive belt. If you need the 7 blade fan for adequate cooling maybe need two belts somehow.

If not, a smaller fan and "standard duty" fan clutch can reduce belt load. As several have posted, a steel fan pulley may do better vs aluminum also.

I might have to go with the standard clutch combo... I hate to switch. Right now the squeal is very light and at about 4-4500 rpm. The only thing that it could be of help is the two belts around the fan. I just don't think there is a good way to do that with my setup. But, I will continue to brain storm.
Or I just will shift prior to the squeal. : )

As a TEST, you could remove the Fan and Fan Clutch and use shorter bolts to temporarily secure the pulley to the water-pump; Then test run the engine for a brief period to see if that eliminates the squeal.

Try a quality belt..many are complete junk. Gates are at the top of my list. A bit more expensive. Try a ribbed belt if not already.

Actually, I never had much luck with ribbed belts on my old mopars. They always seemed to make some type of noise. I usually look for the non ribbed ones if you find them for your application. Make sure the belt is the correct thickness/width as some are thinner and ride lower in the pulley.

Well,
Just for grins. I turned the Fan belt around. It stopped squealing. I suspect it may not be the direction of the belt as much as re-tightening the belts. My guess is it will start squealing again soon. But, it is surely interesting...

turn it back around & you'll have the ans if it was loose or if the redirection fixed it

Just went through a similar problem with my hot rod; it has a small diameter pulley on the alternator to increase the speed and, therefore, the output. The 3/8" belt didn't sit all the way down into the pulley groove, about .050-.060" of the belt sat above the groove. I replaced the pulley with one that was a little larger in diameter and a has a deeper groove.

I theorize that the increased current draw from the A/C increases the load on the alternator and causes the belt squeal.