1985 Chevy Caprice Compressor problem?

Tiny
SPD264
  • MEMBER
  • 1985 CHEVROLET CAPRICE
Air Conditioning problem
1985 Chevy Caprice 6 cyl Two Wheel Drive Automatic

When I turn the A/C on in my '85 caprice the car vibrates accompanied by a loud noise (I assume that noise is the compressor) and the RPMs dip below 500 when at a stop in gear. If I get on the gas lightly to get the RPMs at around 500-600 the vibrations go away. Also, when driving on the highway or at any speed above 50 mph the car jerks abnormally, as if the compressor is putting an extra load on the engine then taking it off. This happens every 2-5 seconds.. If the compressor is faulty, it still functions because the air coming out of the vents is cold. I looked at the belt and it looked new and the tension seemed o.K, with no signs of obvious wear. Any ideas? Thanks!
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Wednesday, August 5th, 2009 AT 12:49 PM

6 Replies

Tiny
IMPALASS
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Hello -

To better assist you can you tell me your engine size in liter and the 8th digit of your VIN.

I have looked in the manual and it isn't too clear so I will need your help. Does your AC have it's own drive belt? I show the alternator/water pump on one, power steering on one and the AC on one.A total of 3 belts. Is that what you have?

I would still like to know the above. It does sound like your compressor is getting ready to go. Even though it is putting out cool air.

The bearings on the pulley wheel/clutch could be gone. You could remove the belt and see if the pulley wheel turns smooth and freely.
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Saturday, August 8th, 2009 AT 1:17 PM
Tiny
SPD264
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It's a 4.3L V6. You're right about the belts, three of them and the one that runs the compressor is also for the PS pump. Are the bearings / clutch a big job to replace? It's seems like the clutch is engaging and desengaging the compressor at random times, and the loud noise is due to the bearings not doing their job. I should have probably mentioned that the A/C was hardly used for the past 6months. How long do you think I have till the Compressor goes dead? And do you have a ballpark figure on how much a A/C clutch and or pulley bearing replacement costs? Or do I have to replace the whole compressor? Thanks again for your help
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Saturday, August 8th, 2009 AT 1:37 PM
Tiny
IMPALASS
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Hello

Thanks for the info .

You have to have special tools to replace the clutch etc . Me it isn t worth it. My reasons, the AC compressor is just as old as the clutch etc . So the time and money spent doing this the compressor could go out next.

It is my experience and I have had much better results by replacing the whole thing if you are doing it yourself you will need AC gauges etc and have an understanding of the system, servicing etc . Do you have those tools?

If you get a compressor with clutch from say, Auto Zone it can run from about $139 to $238. I have attached a web site (you may have to call them) that I have purchased many AC compressors, condensers, evaporators etc from.

I have also purchased from the dealer . At times the price is close so I would check that too .

Eventually the bearing will go then you will lose your power steering. So be careful .

Does this help you out .
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Saturday, August 8th, 2009 AT 11:40 PM
Tiny
IMPALASS
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Hello -

Oh.......one last thing..........

Also, it looks like you may have some recalls on your vehicle. The dealer may fix these for free. Please contact the dealer service department, give them the VIN number of your car and have them check on these to see if they apply to you.


http://www.2carpros.com/forum/automotive_pictures/248015_1985_Cap_1.jpg

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Saturday, August 8th, 2009 AT 11:43 PM
Tiny
SPD264
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Thanks for the info, I don't plan on replacing the compressor myself. One more question though, I recently had the power steering pump replaced; Can you explain to me how the bearings in the compressor would cause the PS pump to go bad eventually? And can that be avoided by not running the AC or is it inevitable because the pulling on the compressor is always spinning with the engine? Thanks again
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Sunday, August 9th, 2009 AT 12:00 AM
Tiny
IMPALASS
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Hello -

Well, I wouldn't say in this case the compressor caused the PS to go out. I am not sure how many miles you have on the vehicle. Over 100K. That is a lot of miles for bearings and pulleys to be spinning. How many miles do you have?

Your model requires the PS pump and hoses to be inspected every 6000 miles. Now does that mean it is going to fail at 6000. No. But again, if you think of how much that little wheel has been spinning. Wow.

Of course it is possible the strain of the compressor puts a strain on the PS since every time you turn the wheel the PS needs the movement of the PS pulley.

Kind of like shocks. If you don't replace the shocks the car bounces more and that puts a strain on the springs and ball joints etc. Before long your suspension is shot because of a shock.

I feel it was normal for your PS to go out. So I wouldn't concern myself there.

As for the compressor and not using it. The compressor will spin no matter what. Even if the compressor wasn't working it would still spin. Many drive for years with no AC (compressor bad) but the pulley part is just fine.

As for the clutch however, yours would engage and not engage depending on the need for cooling. The cycling you are hearing/feeling is normal. It would have to be checked by gauges of course. Though if it does get low it my cycle more or if a pressure switch goes bad. But if I understand you correctly I think in this case the pulley is just tired and worn and went.

Last, if you notice on engine cleaners they state do not spray on pulleys etc. Because they remove any lubricant. Now many bearings are sealed but. It only takes a small defect and now the bearing starts to deteriorate.

I just replaced the idler pulley wheel on a 1999 Mercedes ML320. Totally disintegrated the pulley and all. The only thing left was the inner part of the bearing and the bolt holding it on.

Again, I think it was just time.
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Sunday, August 9th, 2009 AT 10:50 AM

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