Fried clutch on a/c

Discussion in 'The Big Chill' started by V8Sky, May 23, 2010.

  1. V8Sky

    V8Sky "Scarlett"

    Hi guys,

    Okay, here is the update on my Buick's fried a/c clutch situation with pics. I borrowed the a/c clutch puller from Jason - which was a huge help:TU:
    First I removed the clutch off the spare compressor that I had. Then I removed the fried clutch on the compressor in my Buick. Everything went very easy - but when I tightened down the swapped clutch onto my compressor, it became very hard to turn the compressor by hand. Before putting on the clutch the compressor pulley would spin freely. But once the clutch was installed you could turn the pulley a little by hand until it started to tighten up. Should the clutch just be loosened a bit or might this be a different problem?

    Pic1 - removing the spare clutch
    Pic2 - shot of the fried clutch in the Buick
    Pic3 - shot of the reverse side of the fried clutch once removed
    Pic4 - shot of the spare clutch on my compressor
     

    Attached Files:

  2. V8Sky

    V8Sky "Scarlett"

    By the way, I did not put on the attachment center nut yet on the swapped clutch on the compressor as I wanted to know why the clutch and pulley were getting difficult to turn. Does tightening on the center nut make the difference?
     
  3. V8Sky

    V8Sky "Scarlett"

    I may have the solution to the tightened pulley on the compressor. After doing some reading in the '72 Chassis manual (and thanks Rob for also emailing me the pages) I see that there should be a 1/32" to 1/16" air gap between the pulley assembly and clutch drive plate. This may be my issue as the pulley spins freely when the clutch plate is not pressed against the pulley.
     
  4. CJay

    CJay Supercar owner Staff Member

    That could very well be. You might of pressed it on too much. Back it off and tighten the nut down and see what happens.
     
  5. carmantx

    carmantx Never Surrender

    Yes, you have to have that air gap. That is how the compressor turns on and off when you are not using the A/C. Without the gap, you are turning the compressor all the time. I used to "clean" up the shaft a little bit with very fine sandpaper or emory cloth before putting a new one on.

    And, you found out by now that you can replace the clutch without needing to empty the freon. You are not opening the system by replacing that. Replacing the front seal on the compressor, behind the clutch, is a different story.
     
  6. V8Sky

    V8Sky "Scarlett"

    Thanks Jason and Mark,
    I backed the clutch off a bit, tightened down the nut, and left a small air gap between the clutch drive plate and the pulley. Now the pulley spins freely. The clutch does not move - which I'm hoping should be correct? I still have to dig up an a/c belt which I think that I have in the garage, put the belt on the a/c pulley, start up the Buick, and see if the clutch and compressor kick on.
     
  7. cstanley-gs

    cstanley-gs Silver Mist

    Thanks for posting your results Chris.
    If the wiring is hooked up now you should be able to turn it on and hear the clutch engage. (thats if you want to test before you can get a fan belt)
     
  8. CJay

    CJay Supercar owner Staff Member

    The compressor not turning is not a good thing. You should be able to turn it with some resistance. Im suspicious that the reason the clutch burned up in the first place is that the compressor siezed. Be careful starting it and turning on the A/C. You should know within moments if the compressor is siezed:pp
     
  9. V8Sky

    V8Sky "Scarlett"

    Hi guys,

    Okay, now that I'm done for the night I can post my update. I backed the clutch off the pulley to make the air gap. Then I put on a new a/c belt. The clutch did not turn by hand once tightened even with the air gap. Started up the Buick, and the belt was spinning the pulley with no problem. Turned on the a/c and the compressor kicked right on and cold air came through the vents! I waited two minutes and the cold a/c was working well. Turned off the a/c, saw that the clutch shut off, then waited another minute and put the a/c on again, gave the Buick a little gas and heard a loud squealing noise which went away pretty quick. I repeated the step again and no squeal the second time. Any idea why there would be a squeal? But it seems like I fixed the problem as the air conditioning works again - I might make the air gap a hair wider as it looks very close right now.
     
  10. CJay

    CJay Supercar owner Staff Member

    Excellent Chris! :beers2: Job well done just like the old clutch. :Dou:

    I would just snug up the belt a little more. Might just be loose. Could also be glazed. Check for any shiny-ness on the sides of the belt. I actually have a Kent Moore belt tension gauge like the one they show in the service manuals to get the tension just right.
     
  11. V8Sky

    V8Sky "Scarlett"

    Hi Jason,
    Yes, I think that I have to tighten the belt a bit more - it was fine with just pulling the pulley, but with the clutch and compressor on the bottom of the belt got a bit wobbly. I'll check the belt as well in the daylight. Thanks for lending me the clutch pulley puller - I'll get it back to you ASAP. Why am I not surprised you have a belt tension gauge - I really need to start buying more tools!
     
  12. CJay

    CJay Supercar owner Staff Member

    I have tools that fix tools. :bglasses:


    Funny, my neighbor was doing front rotors on his daughter's Exterra today. I had to make three trips to my toolbox for him. I told him that every time I had to walk back to my garage, he had to give me a beer. So I drank his beer and made fun of him while he worked on the truck. :bla:

    Everytime he used one of my Snap On's, he said. "wow, I have to get one of these" :grin:
     
  13. CJay

    CJay Supercar owner Staff Member

    No rush. And your welcome. My tool box is your tool box. :beer
     
  14. V8Sky

    V8Sky "Scarlett"

    Another update - backed off the clutch a bit more to widen the air gap. Now I can also turn the clutch with some resistance so that's a plus! Just have to tighten the belt a bit more.
     
  15. 75Riv

    75Riv A.K.A. Harry Clamshell

    Chris, how does the puller looks (measurements?) that you used to take the clutch off?
    Have that center bolt off now...

    :TU:
     
  16. V8Sky

    V8Sky "Scarlett"

    >>Ask Jason Cook on the board as I borrowed the puller from him. Turned out my compressor was toast because even with the new A/C clutch it froze up again shortly thereafter. I just took off the belt and will convert the whole system over to the modern stuff probably next year.
     
  17. 75Riv

    75Riv A.K.A. Harry Clamshell

    Bummer... bought a puller - installer (special for GM 6A compressors) Turns out that the installer has another thread than the shaft of the pump... :Dou:

    Need to make a tool myself.. or is there another way to get the pulley back on the shaft properly?


    [​IMG]

    Was thinking of welding the clutch plate nut onto the installer tool and grinding the nut till it fits through the center of clutch plate :Do No: :Do No:
     
  18. Briz

    Briz Founders Club Member

    Once started and lined up correctly with the keyway you can use a large socket and a rubber mallet to tap it on. Remember, theres a circle clip inside as well as one out side that has to come off before the ctutch will come off the shaft. The one inside is a real PITA.
     
  19. 75Riv

    75Riv A.K.A. Harry Clamshell

    Installing the clutch plate has to be done with the compressor still arrached to the engine (saving the R12 in the system)....I think there isn't enough space left to tap with a hammer
    I only have my spare compressor here from which I want to use the clutch plate...car (71 Electra) is still in winter storage

    thanks for you input
     
  20. SteeveeDee

    SteeveeDee Orange Acres

    IIRC, the belt gets smoked because the shoe doesn't disengage from the pulley. The symptom is that the clutch drags and stays semi-engaged when the A/C is off (the release springs in the shoe get weak). You can replace the shoe only without discharging the A/C, also. Make sure to replace the shoe as well as the clutch (which might not need replacing, depending on its condition), it doesn't always come with it.
     

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