PAG Oil

jonesboy1983 · Post by **jonesboy1983** » 29 Aug 2009, 18:26

Hello. Well I finally got that steering wheel off. Thanks everyone for your help. Now I have a question about PAG oil. Do any of you know what PAG oil I need for a 98 s70? Also, do I have to put PAG oil in the evaporator itself or do I just wait until I replace the accumulator? Thanks!

Post by **Ozark Lee** » 29 Aug 2009, 19:46

It depends on the model number of your compressor as to which PAG oil you should use. There should be a tag on the compressor with the model number. Post the model number back and I will look it up for you.

The way I handle PAG oil is to buy the aerosol cans and just dump the appropriate amount into the low pressure port before I recharge the system with R-134A. If you aren't changing the compressor you have little fear of the compressor itself being starved of oil and the compressor is the only thing that cares about the oil in the first place.

...Lee

jonesboy1983 · Post by **jonesboy1983** » 29 Aug 2009, 20:08

Thanks. So if I am just replacing the evaporator and the accumulator I don't need to worry about PAG oil?

Post by **Ozark Lee** » 29 Aug 2009, 22:26

You should add PAG oil if your replace either of those items but it doesn't necessarily need to be poured into them as you put them back in. The total system oil charge gets distributed in normal operation and VADIS has a guide on how much to add for each replaced part.

For your purpose the most important thing is to get the correct weight of PAG oil for your compressor which depends on the compressor model number. It is more of an issue of how much oil and what weight rather than where it gets injected into the system. The compressor used in each car was not uniform for a given model and year.

I will fire up my Windows partition in the morning and get you the appropriate amount to add to the system for the accumulator and the evaporator. If I forget, bump the thread.

...Lee

Post by **outdoor7or24** » 30 Aug 2009, 07:18

Most likely the oil will be with the compressor.

You can add some, and I should say very little, like less than 2 oz. if you find there is some oil when removing/replacing the evaporator.
Too much oil will cause a decrease in cooling performance, and too little will cause the compressor to starve for oil, and shorten its life.

See what Lee pulls up for you on the specs.

Post by **Ozark Lee** » 30 Aug 2009, 09:01

The VADIS book spec is to add 90cc (3 oz) when replacing the accumulator and 40 cc (1.3 oz) when replacing the evaporator. They are additive so combine the amounts.

...Lee

jonesboy1983 · Post by **jonesboy1983** » 30 Aug 2009, 09:35

Thanks so much. I am actually having a hard time finding the model number on my compressor. I can see the accumulator fine and I figured the compressor was right next to that but I don't see any tags or any numbers anywhere besides a Bosch on top of everything. I am a novice so could be something obvious I am missing. Also, where do I add the PAG oil once everything is reassembled? And will it be okay to replace the evaporator today, the accumulator next week and then add the PAG oil at that time as long as I don't run the system before then? Thanks again.

Post by **confused_al** » 30 Aug 2009, 09:39

In case you go to a shop for evacuation and refill, you need tell them dont put more oil into the system.

Post by **Ozark Lee** » 30 Aug 2009, 12:09

It is curious that yours has a Bosch label. All of them that I have seen are Zexel Compressors.

The compressor is located below the alternator and the idler pulley on the front of the engine. Next to the crankshaft on the engine it is the lowest item on the serpentine belt route.

I buy PAG oil in cans that are like mini R-134A cans and just add the oil through the low pressure A/C port prior to actually charging the system with R-134A. You should be able to get it at just about any auto parts store, NAPA for sure.

Changing the evaporator and then the accumulator later is fine. Doing it the other way around is not fine. You don't want the accumulator to be open to the air for an extended period of time. It has a desiccant that absorbs moisture and that will be ruined if it is left open to the atmosphere for much more than the time it takes to actually install it.

After you install the accumulator at least get a vacuum pulled on the system as soon as you can.

...Lee

Post by **outdoor7or24** » 30 Aug 2009, 12:22

If you need a vacuum, you can get one from Auto Zone, under their loaner tool program.

I am sure you may already know, but pull a vacuum and let it sit for a bit to make sure you have no leaks.

Lee, did it specify a weight for the PAG oil in the VADIS? I used 100 weight last time on the 945t.