1998 Chevy Malibu 3.1 with "belly leaking" A/C compressor

grcauto

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Thanks Nickb2

The gauge manifold set I borrowed has a schrader valve on one end of the yellow hose.

Does the schrader valve end attach to the refrigerant can or to the manifold ?
I believe you are referring to the pressure relief valve.
 

JackC

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Bill: My error, it is a depressor pin. Old eyes fooled me. It is used for some other a/c setups, like buildings that have screw on couplings with a schrader valve on the a/c .

The yellow line is always open.

Overly cautious Jack.
 

JackC

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WHICH OIL, PAG 46 or PAG 150? . I can not fine a good specification chart.

My '98 Malibu sticker calls for 12345923 oil that is discontinued and replaced with 12378526 which supposedly is PAG 46.

But, the new 4 seasons compressor from Rockauto came with 3 oz 150 listed as correct for my car. Other compressors for my car also come with 3 oz 150 pre- installed.

NAPA and Orielly web sites suggests 150 for my veh.

Auto Zone web site suggests 46 for my veh.

My A/C experience and knowledge is very limited but here is my take on it. 4 seasons that made the new compressor should know what works best in their unit. The oil does not lub anything else in the whole system, so GM's spec should not matter.

On the other hand, there will be some old 46 left in the accumulator, evaporator and condenser, so maybe it s better to dump the 3oz of 150 out of compressor and go with all 46??

What do you all think??? Or does it even matter???

Jack
 
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billr

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I would use the 150 specified by 4 Seasons. The compressor is really the only thing being lubricated. If the compressor came with oil in it, why are you worried about what to add? Didn't we already discuss that? Add only what is required for the component your are replacing (compressor) and it already has that. I also would not be worried about any 46 that may still be the rest of the A/C system.
 

JackC

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I would use the 150 specified by 4 Seasons. The compressor is really the only thing being lubricated. If the compressor came with oil in it, why are you worried about what to add? Didn't we already discuss that? Add only what is required for the component your are replacing (compressor) and it already has that. I also would not be worried about any 46 that may still be the rest of the A/C system.
Bill: I think you nailed it. But let's look at it again.
The compressor comes with 3 oz. of PAG150. The spec for the entire system new was 9 oz of PAG46. The estimates I found online indicate about 5 oz of PAG 46 would be left in the evacuated and vacuumed system in the condenser, evaporator, accumulator and hoses. Therefore I theoretically would have about 8 oz ( 3 oz PAG150 and 5 oz PAG46) of the 9 oz spec. in the system. Is the PAG150 compatible with the PAG46?

Or, I could replace the 3 oz of PAG150 in the compressor with 3-4 oz of PAG46 ( I have 4 oz PAG46 from my last project) and theoretically have 8-9 oz of PAG46 in the system.

Thanks for helping me, Jack
 

billr

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I think the 46 and 150 will be entirely compatible, you will just end up with a blend that is in-between (100?). I also think the system will work OK with any viscosity within that common 46-150 range. Still worried about the lower viscosity? Keep in mind that higher viscosity is usually desired with higher temps, and we rarely get up to the AZ/NM/FL/TX temps here.
 

JackC

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Bill: I really enjoy getting info from your mind. You think these things out and come up with ideas I respect. I truly appreciate it. It is more than an opinion, it is a lesson. Thanks for taking the fear out of my mind.

I will install the compressor with it's 3 oz PAG 150 , add dye and R134a.
 

JackC

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FIXED 43 degrees F.
I did not add dye thinking that the residual PAG46 had enough dye . I can add later if I have a leak someday. At my age I probably will never have to deal with "someday".
 
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