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Irregular Compressor Operation/Belt rubbing instead of turning compressor

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  #1  
Old 08-09-2016, 08:08 PM
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Default Irregular Compressor Operation/Belt rubbing instead of turning compressor

Hello all,

I have the stock GM compressor installed following conversion by local shop to 134a this summer; I will say its not absolutely as cold but the reduced price of the recharge combined with an empirically leaky system I have no interest in completely overhauling meant it was the right choice this time with local prices being 75+ a can for R12, it still cools good enough even in highest heat.

Anyway, lately the operation of the compressor pulley has been very sporadic; most of the time, it fails to turn or rotate with the belt and instead, the belt, driven by the actuator below, simply rubs itself over the compressor without properly turning it. This results in a lot of excess heat, hot rubber smell and obviously belt stress. It also fails to actuate the compressor and therefore makes my newly charged system blow warm or hot air.

To be clear, this occurs regardless of whether the fans are set of high, auto or off.

Given that the problem is sporadic and has presented itself, resolved itself, and then presented itself again, do ya'll think I am correct in assuming the problem therefore cannot be a physical/mechanical problem with the compressor itself based on the logic that if the clutch were simply broken, it would be broken and that would be that - it would not have sporadically worked in between failures?

Any other thoughts or insights as to how to proceed here? This seems like too simple a fix to bother taking it to a shop but I just don't know exactly how to proceed from here.

Anyone have thought/experience with this type of issue?
 
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Old 08-09-2016, 09:02 PM
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Is the belt tight?

A new compressor, even professionally installed, could suffer from a loose belt, because as the system sort of 'wears in', the belt naturally loosens as it mates completely with all the pulleys.

Check how much flex there is between the compressor and the fan pulley. If you're running a 350 you shouldn't have more than 3/8 to 1/2 inch flex MAX, and that means as hard as you can push on it out in the middle of nowhere.

If you have more than that, just make it tighter.
(';')
 
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Old 08-10-2016, 02:11 AM
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I can only add to Elinor's comments.


As that compressor is quite parasitic, the drive must be optimum.
1. The right belt that means not only long enough. but shaped in cross section to match driver and driven pulleys.
2. Pulley sheaves and the belt must be clean and dry. Free from oil or "belt lube".
3. A new belt can change the AC operation to the good.
4. Clean and tight electricals to the compressor clutch.


Enjoy.


Carl
 
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Old 08-10-2016, 09:19 AM
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Thanks ya'll - you really fixed my thinking here: I was only seeing the sliding belt as symptomatic of some unknown failure and hadn't considered that the belt was simply failing to do its job as one possibility. I'm thinking I might have a slight oil drip going onto the belt or perhaps it is not taut enough.

Tinkering today - will post results once I have something worth mentioning. Thanks again!
 
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Old 08-10-2016, 10:00 AM
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Two more points, one on topic and the other not.

1. Your belt is "slipping". Usually accompanied by a loud howl. It has been my experience, that once that starts, a new belt is mandatory. But, also attention as to a root cause of the belt failure. Just old, being a prime candidate.

2. I watch HGTV quite a bit. Chip and Joanna Gaines' show a favorite.
They live and work in your town. Very attractive. I could move there!
Refurb an older place on the Brazos!!! Not quite as showy as Joanna's doings, but somewhat.

Naah, my kids would flip!!!!
 
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Old 08-10-2016, 11:37 AM
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I actually was out for a pleasure cruise about a week ago and saw them and their van actually in work at a house without cameras around; big three story Victorian with a wrap around porch and what looked to be about 8 fireplaces based on the roof. It's truly gorgeous down here in Central Texas.

Now that's finished law school and am looking for jobs in the area, I'd really like to fix up a place like that too!

I'll also probably just replace the belt to address the stress from the slipping you mentioned. I didn't get the customary howl that you mention and with which I'm familiar after having that problem with my air pump before I decided to do away with that aspect of the system.
 
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