Phil_Gtr

-A/C PAG 150 Oil Quantities after REBUILDING entire A/C on LS1 V8 models-

It is a pretty "obscure subject" to say the least, and I will begin with what is mentioned about PAG Oil in the Official 1999 Service Manual for the Chevrolet Camaro and Pontiac Firebird. The service manual deals with both V6 and V8 engines, and therefore covers all the models in terms of A/C, but I'll do my best to concentrate on the data about V8 engines.

The Official Service Manual for the 1999 Chevrolet Camaro and Pontiac Firebird consists in 3 Volumes, and the operations on the HVAC system (A/C system) is detailed in the 1st Volume.
https://cimg2.ibsrv.net/gimg/ls1tech...ebc8ea93ec.jpg
https://cimg3.ibsrv.net/gimg/ls1tech...98c4f19254.jpg

As a general information, it is repeated several times throughout the Service Manual that the A/C System 0-Rings and Fittings should ONLY be lubricated with "Mineral Base 525 Viscosity Refrigerant Oil or equivalent" (GM 12301108 Oil or equivalent, like the "IG-LO 20-9512 A/C Refrigeration Oil 525 Viscosity" for instance).

PAG 150 Oil Quantities :

Compressor Replacement (5. 7L ) Chapter (Removal Procedure, Installation Procedure) _ Pages 139 to 142
https://cimg4.ibsrv.net/gimg/ls1tech...85060f7a5e.jpg
https://cimg5.ibsrv.net/gimg/ls1tech...e497c7c4f1.jpg
https://cimg6.ibsrv.net/gimg/ls1tech...a410373e1c.jpg
https://cimg7.ibsrv.net/gimg/ls1tech...5f4bfdab90.jpg
In this chapter we can read at page 171 :
Use the following procedure in order to install the polyalkaline glycol (PAG) refrigerant oil.
• If the compressor is being replaced, drain the refrigerant oil from both the defective compressor and the new replacement compressor.
• Measure the amount of oil removed from the defective compressor.
• If the measured amount is less than 30 ml (1 oz), add 60 ml (2 oz) to the new replacement compressor.
So, the total amount shall be between 2 oz if there's no more PAG Oil (like when the compressor blew up), a maximum of 3 oz if there's less than 1 oz of PAG Oil remaining in the compressor to be replaced, and SOME UNSPECIFIED MYSTERIOUS QUANTITY if there's more than 1 oz of PAG Oil remaining in the compressor to be replaced.
I'm just starting getting very confused ... but, let's move on.

Accumulator Replacement Chapter (Removal Procedure, Installation Procedure) _ Pages 186 to 187
https://cimg3.ibsrv.net/gimg/ls1tech...275c611a6f.jpg
https://cimg2.ibsrv.net/gimg/ls1tech...5652b31354.jpg
In this chapter we can read at page 187 :
1. If installing a new accumulator, add 30 ml (1 fluid ounce) of polyalkylene glycol (PAG) synthetic refrigerant oil GM P/N 12345923.
Well, accumulators are usually sold without being pre-filled with PAG Oil, so the quantity of PAG Oil in a OEM accumulator shall be 1 oz and that's it, pretty much self explanatory.

Now we enter UNCHARTED TERRITORY (read at your own risk).
Refrigerant Oil Distribution Chapter _ Page 216
https://cimg8.ibsrv.net/gimg/ls1tech...871de66271.jpg
In this chapter we can read :
You must add new oil to the system whenever you replace components, as follows:
• Compressor : The compressor requires 240 ml (9 fl oz) of PAG refrigerant oil. Replacement compressors will not have oil in them. Add the correct amount of oil to the replacement compressor before installation.
• Evaporator : Add 90 ml (3 fl oz)
• Condenser : Add 30 ml (1 fl oz)
• Accumulator : Add 105 ml (3.5 fl oz)
WHAAAAAAAAAAAAT ?!?
9 oz in the compressor, where did they pull out that number from ?!? And the accumulator was filled with 1 oz of PAG Oil when replaced in the previously mentioned chapter, and now it's 3.5 oz ?!? And for the rest of the mentioned quantities, well, I don't know anymore what to think of it.

Conclusion :
The A/C system must contain PAG 150 Oil because the compressor must remain lubricate at all time. After a certain time of running the A/C system of a car will distribute that PAG oil all around the A/C system, and the PAG oil will tend to move through the system BUT remain in about the same quantities in every major part of the system (compressor, condenser, evaporator, accumulator). When the A/C system is 1stly installed at the factory, certain quantities of PAG Oil are put in each of these major parts of the A/C system, and that's the exact same quantities that shall be these major parts of the A/C system all through the lifetime of the car.
Unfortunately these factory PAG Oil quantities seem to have disappeard from the litterature after the LS1 Camaro model and Firebird model have been discontinued.
A very reputable mechanic (who shall remain nameless) gave me the following PAG Oil quantities to respect, may that be during A/C parts replacements or regular maintenance of the A/C system on a LS1 Camaro/Firebird, and from now on I'm going to "religiously"follow these instructions. A LS1 Camaro/Firebird A/C system shall work with :
9 oz of PAG Oil in total.
_ 3 oz in the compressor.
_ 2 oz in the condenser.
_ 2 oz in the accumulator
_ 2 oz in the evaporator

Please, feel free to correct these quantity values, BUT PLEASE, base your argumentation on documented proofs (and not some YouTube video from some risky diyer).

Now, if we had a Canadian technician who actually worked at the Camaro/Firebird A/C assembly line between 1998 and 2002 at the St. Therese GM Factory (in Ontario, Canada), and who would come to preach the good word telling us WHICH EXACT QUANTITIES OF PAG OIL WERE PUT IN EACH PART OF THE A/C SYSTEM ON THE ASSEMBLY LINE, then we would be SAVED.
Amen !

B52bombardier1

Absolute precision is not required here though I'd tend to add more oil than less because you lose some to leaks with time. I'd use the amount of oil that the compressor manufacturer recommends plus some for the condenser, the lines and the accumulator / receiver-drier. And then don't pour it all into one place. Pour some into the compressor and spin it a little to circulate it - no need here for a hydro lock. Then some into the lines and condenser and the accumulator. Stick close to the recommended oil for the system as recommended by the OEM plus a little. You should be fine.

The goal is to avoid a dry startup of the compressor. I routinely see 38 degrees F at the center vent meat thermometer without a lot of hand wringing about too much or too little PAG oil.

Rick

Phil_Gtr

Here are the Delphi instructions :
Delphi CS0134
OIL BALANCE PROCEDURE FOR THE COMPRESSOR
1. Prior to installing the new compressor, drain the refrigerant lubricant from the old compressor into a clean, calibrated measuring container.
In my case 0 oz 'cause the compressor blew up and is empty.
2. Record the amount of oil removed from the old compressor.
0 oz (compressor blew up and is empty)
3. Drain the refrigerant lubricant from the new compressor into a separate clean, calibrated measuring container.
4. If the amount of oil removed from the old compressor is less than or equal to 2 fl. oz. (60ml.) add 2 fl. oz. (60 ml.) of oil drained from the new compressor back into the new compressor.
5. If the amount of oil drained from the old compressor is greater than 2 fl. oz. (60 ml.) add the same amount of oil drained from the old compressor back into the new compressor using oil that was drained from the new compressor.
6. Rotate the compressor clutch driver at least four revolutions prior to installing the compressor on the vehicle using a clutch hub turning tool, Delphi CB10049 or a spanner wrench.

Same issue as before, but with other quantities.
Truth is, a compressor requires a certain "range" of PAG Oil quantity, no more, no less.
In the case of a compressor having blown up, all other components of the A/C system must be replaced, and a precise quantity must be added to each component of the A/C system prior to installation ... and NOBODY knows exactly how much, it's always sort of a "mambo jambo" with quantities ranging from simple to double.

vikingramair

This is so incredibly confusing. I'm going to replace the compressor + Receiver Drier / Accumulator + Orifice Tube + all hoses. Think I'll also order a new Evaporator Core just to be on the safe side.
Just pray to God when times come for oil fill up..........

BigBlackCamaro

If a compressor went bad the condenser should be replaced or at least flushed thoroughly.
The accumulator should be replaced whenever the system is opened.
The evaporator should only be replaced if needed so it should be flushed out.

So at this point everything should be free of oil.

ALWAYS replace the orifice tube.
I always drain the compressor, and put it all together.
When assembling parts like o-rings use motor oil or anything other than synthetic refrigerant oil like PAG 150. Why? PAG, POE, will suck moisture right out of the air and corrode.

Now think of operation. The accumulator lets refrigerant/oil accumulate instead of going into the compressor as a liquid.

Take an 8 ounce container of oil and pour 3 ounces in the compressor and the rest goes into the accumulator. Doing it like this assures you won't suck it out with the vacuum pump.

Which leads to evacuation. You HAVE TO use a vacuum pump. First pressure test it with dry nitrogen and bubble check the joints with leak detector soap bubbles.

Then connect a vacuum pump and MICRON GAUGE. Once you pull a good vacuum, probably 8 hours because no DIY'er owns a real vacuum pump so you have to rent one. Do a vacuum hold test.

Impossible right? No one has the right tools. So why worry about oil quantities per component (because it doesn't matter) if you're going to leave moisture in the system.

SO you need to think backwards. First, once I get this together am I going to be able to evacuate it and see how many microns it holds? If your answer is no then why are the questions above so specific. All I see is basic remove and replace and nothing about proper leak checking, evacuation, and charging.

And yes, I know people claim they have just dumped the required amount of refrigerant in and it has cooled fine forever, no evacuation, nothing.

My response comes from 29 years of HVAC experience.

Heres the evaporator out of my 2002 SS that has 54k miles and sits in the garage, gets started maybe twice a year. Just lost all the refrigerant over a period of sitting 6 months.

vikingramair

I will just do the hardware installation, connect all the wires with the new compressor and to the Accumulator. Therefore, I need to know how much oil to pre-fill the system and in which parts before I leave the car to an AC company that will handle the procedure to fill the AC system and make it operational.

BigBlackCamaro

Assuming it's a 4th gen f body it takes 8 ounces of PAG 150. Put approximately 3 in the compressor and the rest in the accumulator. Take it to have it finished within a day or less and be sure to tell them you put oil in it.

vikingramair

Out of curiosity, I drained my new Delphi compressor of oil and measured it. It contained 2dl aprox 7oz