1993 GT a/c clutch is broken - how hard is it to fix?

My factory air stopped working today - when I looked under the hood and cycled the air conditioner on and off the clutch tried to engage but the rubber part has been split all around the middle section. I was able to spin the center shaft by hand with the engine off and it seems that the compressor is still ok and the clutch will still engage normally but the rubber hub is torn so it will not spin the compressor. How do I change this part? How hard is it? How expensive? Thanks.
 
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I'll be doing the same thing this week since my clutch just went out. New they are about $100-140. To install then you need some deep snap ring plyers and just regular sockets and such. You might need a puller if the clutch is really on tight to the compressor. The parts of the clutch are held to the compressor with a bolt in the center, and two snap rings. Remove the snap rings BEFORE you use a puller, or you will do like me and break off the nose of the compressor! (JB Weld was my best friend that day!) I found it is a bit easier to unbolt the compressor, keeping the refrigerant lines attached, and then you can actually reach in and see the snap rings. Temporarily reassemble it and then you should check the air gap to make sure it can engage. Once you know it has the right gap, then you can put it all back together.
 
The A/C clutch is about $100 new or you can buy a compressor from the junkyard with a working clutch for about $50. The puller is about $16 if you have to buy one, Autozone will rent you one for free.

Other than that, follow trbkrb 's advice.
 
I just had the same problem...you don't have to replace the whole clutch.. you just need the hub...I got the part from Rockauto.. it was Motorcraft # YB289A...I had to unbolt the compressor from engine( I believe I left the compressor mounted to the mounting bracket) my brother-in-law had the puller I needed but you can probably rent or borrow one from Advance Auto Parts...Hope this helps..
Joe
 
Thanks all! I think I will try to find that hub part only since it will be the cheapest route and I do not want to loose my freon charge. The rubber part seems to be spun and broken in the middle and that is all that appears to be bad. Strange how the a/c was working perfectly all day in 100 degree weather for days and when it was actually only 90 degrees out it lets loose 10 minutes from home.
 
I have replaced the clutch hub twice on 5.0 Mustangs and it has been an effective fix when the hub failed. If the elecromagnet coil is functioning properly,and the clutch does not engage and turn the compressor, then the hub is the problem.

The A/C clutch is about $100 new or you can buy a compressor from the junkyard with a working clutch for about $50. The puller is about $16 if you have to buy one, Autozone will rent you one for free.

The clutch hub is usually what fails, the rubber shock damper shears off from the steel hub and plate. The pulley turns, but the hub doesn't when you power up the A/C The hub comes off without much problem if you have the puller. You don’t have to do anything with the refrigerant (R12 or R134a), you can replace the clutch without draining and refilling the system. The snap ring hiding inside the hub is the only tricky part.

A few simple electrical tests are advised before popping out the wallet to buy a clutch assembly. With the engine running, use a test light connected to the 2 wires on the A/C clutch harness to make sure you have voltage when you turn the A/C on. If the system is low on refrigerant, the clutch will not engage (safety feature, keeps you from burning up the compressor due to no oil). There is an aluminum canister on the firewall with a large hose leading to the A/C compressor. There is a pressure switch on it with a 2 wire connector: pull the connector off and jumper the wires. The compressor circuit will power up, and the test light will light if the electrical circuit is good. This test is also a good way to check the compressor & clutch if the system is low on refrigerant. You can jumper the wires and the compressor will turn if the clutch is good.

The clutch also has a relay that shuts off when you go to WOT (wide open throttle). It is located on the passenger side inner fender well. The close proximity of the relay to the headers can cause the insulation on the wiring and the relay socket to deteriorate. The relay can become non functional when this happens.


Diagram courtesy of Tmoss & Stang&2birds
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