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1968 Factory A/C Clutch heating up


I'm trying to diagnose a problem with the factory a/c on my 1968 Mustang.

Here's the situation..

The clutch is getting hot because it hits a certain spot on rotation that is sort of like a brake being applied.

I was recharging this system with es12a cause as you know the r12 just isn't to be used along with other problems. During the re-charge the low side stopped showing any pressure, the high side remained unchanged.

I was thinking this might be a compressor problem, but after driving a couple weeks and hooking the gauges up again, I switch the A/C on and I get pressure, but now I notice that the clutch appears to keep "sticking" which is causing it to get really hot. Now with the belt off, engine off and key turned off the clutch spins freely. I turn on the key and turn the a/c on (engine off, just to send the power to the a/c clutch brushes). Now the clutch still spins easy but it has a "catch" like a break being applied. If I hold pressure to spin, it gradually passes by this point to spin freely again and this repeats.

Is it possible that this is from an overcharged system and the "braking" effect is actually the valve trying to squeeze the liquid refrigerant through?

Or is it the clutch going bad or something else?

It's the clutch that is worn out.  Your best bet is to go ahead and replace the entire compressor with a new one because just replacing the clutch will only delay the inevitible compressor failure in the near future. 

I pulled the clutch and the compressor.  I tipped the compressor upside down to see how much oil would come out... not one drop.  I'm sure this thing is in it's last leg as it looks like an original unit with the Ford tag.

Ford used the "York" brand compressors back then, and they were not the best.  Today, you should consider replacing it with a Sanden.  The repop 139 buck compressors are crap.  If you are going to go through with all the trouble of replacing the compressor, get the Sanden.  There are some mounting adjustments, but nothing you can't handle. 
Here are some links for ya to get ejumicated.   ;D


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