fragmare

So I'm pretty sure I need to do some work on my A/C Compressor (or just replace it) in my 93 DX. It has begun to grind and clunk but *ONLY* when the clutch is engaged. The pulley spins fine on its own. The clearance between the clutch plate and pulley is within spec.

I'm suspecting it's the internal ball bearings (see attached diagram) that are driven by the orbiting spiral action, since the pulley does not make any noise, by itself, and seems to spin just fine. Any input before I go tearing the thing apart?

The bearings I am suspecting to be shot are the ones circled in red.

axis11

With engine off, try rotating the compressor by hand. Feel for roughness and noise as it turns. If its quiet, remove belt and turn clutch pulley and idler pulley by hand. Sometimes these bearings will only make noise under load. Feel for roughness in the bearings. If all the mentioned bearings are fine, I would suspect the seal between the two spiral assemblies are worn enabling the the two spirals to have metal to metal contact and make noise. The internal bearings would be the last on my list. Is the compressor able to provide ideal pressures?

fragmare

It still blows cold, yes... it's just gotten noisy. I haven't gotten a set of manifold gauges on it yet. I'm out there working on it now. Will check back in with more findings later.

fragmare

Okay, so here's what I found. For the sake of being thorough I took 3 separate videos.

#1 is the idler pulley. It spins freely without any noise. I thought it had too much play, but the pulley nut just needed tightened a little bit.

#2 is the compressor pulley. It also spins freely but not without some noise. There is also a tiny bit of play in there. Correct me if I'm wrong, but I don't think it should have any play or noise whatsoever when spinning.

#3 is the clutch plate. It spins easily by hand and does not have any play, but there is a slight tick at a certain point in the rotation. Seems like that tick should not be there...

Seem like a clutch pulley bearing to anybody else?

fragmare

So, I think I know what's going on now. While at rest, the clutch plate to pulley clearance is within spec. But due to (what I believe to be) a faulty clutch pulley bearing, when spinning, the pulley is allowed to creep up the spindle and/or wobble enough to the point where it grinds against the clutch plate... but only while the clutch plate is engaged.

I'm going to order a new clutch pulley bearing and lay off the A/C until it arrives. After installation, I will recheck the clutch to pulley clearance and add/remove shims as needed. Hopefully that will fix the issue.

axis11

From video no.2, clutch pulley play is not supposed to be in there. Definitely a clutch bearing going out.