Lack of pag oil in compressor

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Chadlow21
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Lack of pag oil in compressor

Post by Chadlow21 »

2000 Pontiac Formula.
I was told by the previous owner that the A/C in the car just needed a charge. After filling it I found a small leak in the low pressure hose running from the accumulator drier to the back of the compressor. The air worked great until all of the freon escaped from the leak(took about 45 minutes).
I have bought all of the parts to repair the system. Hose, drier, and new orifice tube. When I pulled the compressor out of the car, I went ahead and drained it to try to get an idea of how much oil to put back in.
I was only able to get just less than 2oz of old oil out of the compressor after trying for about 20 minutes. There was also no oil to be found in the old accumulator.
When I filled the compressor back up with new oil, it would only hold about 3oz before it started overflowing out of the discharge port.
My questions are, would that little hose leak cause me to lose that much oil? The system is supposed to hold 9oz total.
Would the old oil still be in the condenser and evaporator?
Should I add the remaining 6oz that the system is supposed to have to the new accumulator?
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Cusser
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Re: Lack of pag oil in compressor

Post by Cusser »

Chadlow21 wrote:I was told by the previous owner that the A/C in the car just needed a charge.
I would NEVER believe such a thing. Unless the rare vehicle that just seeps refrigerant over a decade or so, there's always a real leak.

Chadlow21 wrote: I was only able to get just less than 2oz of old oil out of the compressor after trying for about 20 minutes.
I've replaced two compressors in the last 2 years - 1988 Mazda truck (compressor seized, 200K miles) and 2005 GMC Yukon (compressor was slugging, AC belt breaking, 160K miles). The Mazda still cooled fine the day before it seized one hot October morning (Arizona), and the Yukon was also cooling well. Neither had any measurable amount of oil in the old compressor. I added about 80% of the full/specified oil amount.

So that's what I'd do if it was mine.
Chadlow21
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Re: Lack of pag oil in compressor

Post by Chadlow21 »

Okay, so since I was only able to get 3oz of new oil into the compressor, should I just add the remaining 6oz of oil that the system calls for to the accumulator?

And how do i properly add oil to the new accumulator? Do just I pour it into the inlet?
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Cusser
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Re: Lack of pag oil in compressor

Post by Cusser »

Are you turning the compressor by hand, and it's really full? If so, I'd say add to accumulator, just pour in, oil will distribute once it gets running.

Be sure to rotate the compressor at least 10 revolutions by hand once it's all bolted up and connected, before pulling a vacuum.
GM Tech
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Re: Lack of pag oil in compressor

Post by GM Tech »

On V-7 variable displacement compressors as is yours- oil should be drained/added through the oil drain bolt/plug on the side of the compressor. There are three pressure zones, suction, discharge, and crankcase- there is at any given time a reservoir of 3 fl ozs in the crankcase. Your new compressor instructions should have told you this- and most new compressors come with system oil charge already in them- should be labeled and in the instructions- being a couple ounces over is better than a couple shy- so err on the safe side. Having put the oil in the suction port explains why it did not all go in- and it will take time to bleed over to the crankcase- but you should be okay- adding remaining oil to accumulator is fine. Go ahead and drain old compressor- you should find more oil in the crankcase.
Chadlow21
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Re: Lack of pag oil in compressor

Post by Chadlow21 »

GM Tech, I did not buy a new compressor so, I don't have any instructions for it. The old one works fine. I will try to drain it again using the drain plug on the side.
Chadlow21
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Re: Lack of pag oil in compressor

Post by Chadlow21 »

Cusser, I did turn the clutch while I was filling the compressor. I did this until I couldn't get anymore oil into it.
Chadlow21
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Re: Lack of pag oil in compressor

Post by Chadlow21 »

What was confusing about this is that the old accumulator was completely dry when I took it out of the car. When I went to drain the compressor and I was only able to retrieve less than 2oz out of it, I was wondering where the rest of the 9oz of oil that the system is supposed to have went to. I would have felt much better about the whole thing if I would have been able to get 6oz or so to drain out of the compressor. I wouldvery just added that 6oz back into the compressor and added 2oz to the accumulator and called it good.
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Cusser
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Re: Lack of pag oil in compressor

Post by Cusser »

Chadlow21 wrote: I was wondering where the rest of the 9oz of oil that the system is supposed to have went to.
The remainder of the oil is gone. Gone forever.
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