Is my new compressor bad from the part store Low/High same pressure

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grey169

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Friday while driving down the road I had a squeal and a shutdown of the engine. The compressor bearing had locked up and shredded the serpentine belt.

After a tow to the house I replaced the belt and the compressor (another nightmare) and she ran like a top.

I did the tow errand that I needed and began the process of adding fluid.

I did a vacuum and it held that vacuum for over an hour. I added R134a with the truck running, AC on High and waited. Low pressure increased to 85. I watched the high side slowly creep up to 85 as well.

The high side valve is shut off and only the low side is open.
Does this mean that the compressor that I just got (and spend 5 hours replacing egads what a PITA) is bad?

Last year I replaced the condenser and expansion valve (for the rear) and the dryer and it blew extremely cold so I know that system is otherwise working.
 

stamp11127

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Did you pull the orifice tube and check for debris before swapping compressors? The bearing or the compressor may have locked up. If the orifice tube is loaded with metal it was the compressor that seized.

Compressor warranty usually stipulates that the accumulator or receiver dried needs to be changed with the compressor to be valid.

Pressure readings seem to be static values - makesure the compressor is running.
 
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grey169

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The new compressor is not running. The electrical connection is connected. Once the low side has enough pressure the compressor should turn on, correct? It should be 12 V at the connector?
 

stamp11127

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Correct 12 volts at the compressor. Low side switch should close with that high of pressure. You can jump the low side switch if you don't have 12 volts at the compressor.

Did you add pag oil to the compressor?
 
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grey169

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I added 3 more oz. It came with 3 already.
I will check low pressure switch. Is that by the condensor?
 

stamp11127

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High pressure switch is usually by the condenser, low pressure is either in the line going from the evap to the compressor or in the accumulator. Of course it will be in a position to almost not see it.
 

gixer2000

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Have you checked the fuses? Its ppretty common for the fuse to blow if the clutch burns up
 
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grey169

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I have not checked fuses. I will do that tonight if I am able. I was able to find the low pressure switch. It has 12VDC on the one wire. I jumpered it and still have no engagement of the clutch.
 

stamp11127

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With the low pressure switch jumped, see if you have 12 volts at the connector for the compressor. If you do then check the compressor clutch coil for resistance using a meter.
 

JExpedition07

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I just had the same occur, my expy sat and didn’t get driven for 7 days. I started it up and heard a screaming belt..... rebuild compressors don’t seem to work well.
 
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