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A/C Screeeeech....

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Old Aug 17, 2024 | 07:15 PM
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Default A/C Screeeeech....

Hi All,

My 69 427 390 started screeching when I engaged the AC a bit ago, but if I engaged say at a stop light all was ok. Now it is much worse. I suspect it is the clutch. But would like thoughs on if my diagnosis is correct.

Quick question, what is the skill level to replace the clutch in the AC? (if that is the issue) I have the luxury of having an Aerospace engineer next door who is also an old car buff. With his help and vast array of tools I can accomplish more than I can on my own. But if it is truly something complex, I might leave it for winter service at my mechanic. Or do you just replace the whole unit - I imagine that is more expensive than a rebuild either by me or at the garage.

Thoughts?

Thanks in advance.

Hans
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Old Aug 17, 2024 | 08:39 PM
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AC screeching on engagement? First thought is loose V belt, or glazed V belt.
Before I would even consider the clutch. (Highly unlikely in my opinion) I would inspect, adjust the belt.
If the belt is glazed, replace the belt. This should be in anyone's skill level.
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Old Aug 18, 2024 | 09:11 AM
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Hi 4-Vettes
I will replace the belt and see what happens. Thanks for the advice.

Best
Hans
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Old Aug 18, 2024 | 10:35 AM
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Or.....
Somebody added refrigerant that wasn't necessary, and is locking the pump.

You want to discharge that right away.
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Old Aug 18, 2024 | 11:04 AM
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Hi All,

I just had a look and the belt looks to be in very good conditioin but it does have some play in it, Not nearly as tight as the alternator belt. So going to retighten it.

ramair_bryan - Thanks for the reply, but I think that is not an issue, it was running quite well in the beginning of the summer. I now thing the belt is the target.

Best,
Hans
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Old Aug 18, 2024 | 11:59 AM
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Alas it was just the belt being loose. All good now. Sorry to bug you all for such an ameturish question........Have a pleasant Sunday.
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Old Aug 18, 2024 | 01:24 PM
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Originally Posted by HCK
Alas it was just the belt being loose. All good now. Sorry to bug you all for such an ameturish question........Have a pleasant Sunday.
Do not worry about asking any question, amateurish or not. We've all been there with something obvious staring us in the face, yet we don't see it. It's the easy fixes that are sometimes overlooked because we tend to jump to the worst case scenario. Unless you live in Tanzania, apply Occam's Razor: hoof beats are usually horses not zebras.
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Old Aug 18, 2024 | 08:19 PM
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Originally Posted by 67:72
Do not worry about asking any question, amateurish or not. We've all been there with something obvious staring us in the face, yet we don't see it. It's the easy fixes that are sometimes overlooked because we tend to jump to the worst case scenario. Unless you live in Tanzania, apply Occam's Razor: hoof beats are usually horses not zebras.
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