Clutch slipping problem

[Mike Holleman]

Any help will be appreciated from the A/C experts on the site. My Sanden SD7 compressor has started squealing. At first it was a little squeal on start up but now it is squealing until the RPM comes up to cruise speed. No the belt is not loose. It is metal to metal in the clutch. Any ideas as how to troubleshoot this one?
Mike Holleman

[engine]

Does it squeal with the A/C on or off?
if you take the belts off the clutch and try to spin it free-hand (with the engine OFF!!!!!), is it smooth?
possibly the bearings in the clutch are shot. Replace the clutch.

[Mike Holleman]

It only squeals when the A/c is on. I haven't tried free turning the clutch, but will tomorrow. What I have done is hook a direct battery source to the compressor to see if there may be voltage drop. Made no difference. Also I pulled the outer plate off the clutch to check the surfaces. It shows some grooving and wear. This unit is about two years old and not been heavily used. It started as an occasional squeal on A/C start up and has gotten progressively worst. The Power Tour was hard on it.
Mike

[Mike Holleman]

I just realized I posted this in the wrong place. It's not a cooling issue.
Sorry bout that!
Mike Holleman