Author Topic: AC compressor knocking  (Read 2050 times)

Offline tyler5726

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AC compressor knocking
« on: September 24, 2017, 07:28:34 PM »
My AC compressor on my 80 pickup makes a knocking noise when the AC is on or off. It would get faster as I start to accelerate. The other day the belt broke off so of course, no more noise. But I live in Texas and would love to get the AC running again. What could be causing the compressor to knock when it's on or off? Could it have been the belt? Any info is appreciated! Thanks

Offline Rapid Roy

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Re: AC compressor knocking
« Reply #1 on: September 24, 2017, 09:05:34 PM »
Guessing that you have definitely determined noise is coming from compressor. Sounds like the clutch assembly/pulley bearings are bad causing noise with no AC on. If there has been some replacing of other parts, check that the belt is aligned correctly with the other pulleys.
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Offline VileZambonie

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Re: AC compressor knocking
« Reply #2 on: September 25, 2017, 06:31:06 AM »
 Make sure it is securely mounted. If it secure then it's probably time to replace the compressor. You will need to replace the drier, and orifice tube and I would recommend flushing the system of any foreign materials.
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