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FYI: I could not find this information so I thought that I would post it for anyone else that needs help. I bypassed my AC Compressor with a 6K739 belt that is 74.5" long Outside Diameter. This belt cost me $20 and worked perfectly. I had tried a 74.125" length and that was to short. The 74.5" length fit perfectly.

The reason that I needed to bypass the AC is that first the compressor or clutch froze up and would not turn. I first pulled the AC relay so it would not try to turn on which worked well for a couple weeks. Then I started getting a noise from the AC related to engine speed. I needed to bypass or replace the compressor. I am bypassing for now with this shorter belt.

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I needed to bypass or replace the compressor. I am bypassing for now with this shorter belt.

The bearing is less than $10.00 at a bearing supply house. The bearing can be changed without messing with the refrigerant charge. All it takes is some special tools to pull the clutch plate and pulley. Autozone has some of them in their loan a tool program. The others are available from any decent parts store. Much cheaper than a new compressor.

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

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I have done that same with my 96 Deville, a search here should turn up members who have done the same thing.

Its a great way to postpone replacing the compressor till you are ready.

Be advised that its possible that your cooling fans may not run at high speed as they do when the AC system is on, and you may see higher peak temps as a result. My compressor got to the point where it blew fuses and I needed to disconnect it.

Pre-1995 - DTC codes OBD1  >>

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Interesting KHE,,, I might take your advice and pull the bearing and see if that is the problem, before purchasing a compressor. I imagine I can tell if the compressor is bad by trying to turn it by hand once the bearing is removed?

Also, BobbybyFisher, That might be a good reason to remove the AC relay under the hood, I guess even though I have the shorter belt on the car now. I suppose if my wife drives the car and hits auto on the climate control the AC Comp clutch will energize even though it is not spinning and possibly blow a fuse or something I don't need it doing. With the shorter belt on the car I might as well pull the relay since it is not going to work anyway, like I had done before I put on the shorter belt to keep the compressor from trying to start with what I thought was a frozen compressor.

I actually had smoke coming from the comprssor when I first tried the AC this year. I of course turned it off right away. Then I had the car idleing with the AC off and when I turned on the AC it snubbed the motor. That is why I figured the AC compressor was frozen, but it sounds like you guys might be saying it could also be the bearing. My thought was that the bearing would not allow the AC pulley to free wheel or spin with the AC turned on or off,, Am I correct in that thinking? My pulley was working up until I started hearing the noise that I didn't like and that led me to putting on a shorter belt, so the pulley would not have to turn at all. The fact that the AC would stop the engine in its tracks led me to believe a froze up compressor. Any thoughts?

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The pulley bearing is frozen. If you remove the clutch, pulley/bearing, you will be able to turn the compressor shaft.

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

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The pulley bearing is frozen. If you remove the clutch, pulley/bearing, you will be able to turn the compressor shaft.

I guess that I don't understand the compressor. If the pulley bearing was frozen. Would I have been able to start the car with no problems and the serp belt would just spin the belt pulley with no problems?

I envision the bearing that you are talking about as being the bearing inside the pulley that freewheels all the time the car is runing, and it would seem that if that was frozen, the minute the pulley spun it would be trying to turn the compressor. I must not understand the AC compressor clutch system. I was thinking that the pulley freewheels all the time and when the AC is turned on the clutch would lock up to the pulley and turn the compressor shaft. What am I missing here? Thanks again, and please forgive my lack of understanding.

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I guess that I don't understand the compressor. If the pulley bearing was frozen. Would I have been able to start the car with no problems and the serp belt would just spin the belt pulley with no problems?

I envision the bearing that you are talking about as being the bearing inside the pulley that freewheels all the time the car is runing, and it would seem that if that was frozen, the minute the pulley spun it would be trying to turn the compressor. I must not understand the AC compressor clutch system. I was thinking that the pulley freewheels all the time and when the AC is turned on the clutch would lock up to the pulley and turn the compressor shaft. What am I missing here? Thanks again, and please forgive my lack of understanding.

Normal operation is the compressor pulley free-wheels until the A/C is requested. The ACM applies power to the clutch coil and the plate pulls against the pulley rotoroface which engages the compressor.

When the pulley bearing gets so bad that it starts to bind up, it will be difficult to turn without the compressor engaged. This is the symptom you are expierencing.

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

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I guess that I don't understand the compressor. If the pulley bearing was frozen. Would I have been able to start the car with no problems and the serp belt would just spin the belt pulley with no problems?

I envision the bearing that you are talking about as being the bearing inside the pulley that freewheels all the time the car is runing, and it would seem that if that was frozen, the minute the pulley spun it would be trying to turn the compressor. I must not understand the AC compressor clutch system. I was thinking that the pulley freewheels all the time and when the AC is turned on the clutch would lock up to the pulley and turn the compressor shaft. What am I missing here? Thanks again, and please forgive my lack of understanding.

Normal operation is the compressor pulley free-wheels until the A/C is requested. The ACM applies power to the clutch coil and the plate pulls against the pulley rotoroface which engages the compressor.

When the pulley bearing gets so bad that it starts to bind up, it will be difficult to turn without the compressor engaged. This is the symptom you are expierencing.

Thanks again for bearing with me on this, I really appreciate it. So right now I have the AC Compressor bypassed with a shorter belt. If I reach down to the AC compressor I can easily roll the pulley (I will call it) with my fingers. Is'nt that the part that would be froze up if the bearing was shot? I guess that I was thinking that I would not be able to move/spin that pulley, you know where the belt normally runs very easily with my fingers if the bearing was froze up. Would that freewheel so nicely if the bearing was froze? My problem was when the AC clutch actuated the car would just come to a stop or start smoking after a time which I thought was an indication of the clutch slipping because the compressor was froze up and the clutch plates were slipping or the clutch grabbed tight but with a frozen compressor it just snubbed the car. Again, thanks for your help, I would like to buy the right part the first time if I attempt to fix this.

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Would that freewheel so nicely if the bearing was froze?

No.

My problem was when the AC clutch actuated the car would just come to a stop or start smoking after a time which I thought was an indication of the clutch slipping because the compressor was froze up and the clutch plates were slipping or the clutch grabbed tight but with a frozen compressor it just snubbed the car.

That sounds like the compressor seized.

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I thought your original post said the belt shredded when the A/C was off. My mistake. It sounds like the compressor has siezed internally. Pretty rare for a HR-6 compressor. The most common failure is leaking case seals on units manufactured prior to January, 2001. The unpainted aluminum ends of the compressor would corrode and allow refrigerant to leak past the o-ring. That is a relatively easy fix - a $25.00 seal kit and a Dremel tool to polish up the o-ring grooves and it is good to go.

Can you rotate the clutch assembly? Grip the outer plate on the clutch face and see if it can be rotated. If not, it sounds like the compressor is siezed internally.

You will need to replace the condenser and orifice tube as well as the compressor. A system flush of the evaporator and lines is also a good idea.

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

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