Automotive Air Conditioning Information Forum

Hello everyone,

I have a 99 GM/Vauxhall Vectra that had a leak and I fixed by replacing some components, but did some mistakes along the way and need help to come up with a plan now... in fact not even using it until I can address --->AC is working and cooling fine btw.

First, it uses a Delphi Harrison V5 compressor (still original from 99) that calls for 7.5oz of synthetic oil SAE J639

I have never worked with AC before and didn't know they had different oil viscosities too... thought it was one fits all or period specific, asked a shop and the guy said "we mostly use PAG46" so I went with it.. yes very dumb mistake, it should have PAG150 it seems... 1st error.

also when replacing hoses, cleaning etc, I am sure moisture entered the system... I washed the compressor insides (just the casing not the part were the pistons are, but still) and hoses were open for a while... 2nd error. (added a new dryer filter at least).

What is the best way to remove oil without disassembling everything again now? if the shop pulls vacuum from the high pressure/liquid side, will it work? I can also remove the fill bolt in the compressor and use a syringe to remove most in the sump there...

Also by researching this, found some saying that running too much/deep vacuum can boil the oil and damage seals, is that true? I refreshed most things and don't want to put at risk... just not sure how it is possible/works.

Thanks in advance!

jm_vectrab wrote: Sun Dec 07, 2025 5:55 am I have a 99 GM/Vauxhall Vectra... .

Yours is not a USA-spec vehicle, so I don't have any information on it.

jm_vectrab wrote: Sun Dec 07, 2025 5:55 am I have never worked with AC before and didn't know they had different oil viscosities too... thought it was one fits all or period specific, asked a shop and the guy said "we mostly use PAG46" so I went with it.. yes very dumb mistake, it should have PAG150 it seems... 1st error.

See "Auto AC Forum Posting Rules", Number 1.

In that same vein, realize that Mobile Vehicle Air Conditioning (MVAC) system diagnosis and repair requires extensive knowledge; years of training, experience, and observation; in addition to the right tools. You can do expensive damage to an MVAC system—or more importantly, injure yourself—by arbitrarily working on a system or by adding unknown quantities of refrigerant and oil. A system is designed to operate on a specific weight of refrigerant and a specific type and quantity of oil. Too little is a problem, and too much is also a problem. Unfortunately, you can't diagnose any system with one of those "quick-fix kits" readily available from discount or auto-supply stores.

That said, what you did isn't dumb...just a mistake due to inexperience and lack of knowledge.

As you correctly pointed out, though, the main difference between PAG-46 and PAG-150 is viscosity.

jm_vectrab wrote: Sun Dec 07, 2025 5:55 am also when replacing hoses, cleaning etc, I am sure moisture entered the system... I washed the compressor insides (just the casing not the part were the pistons are, but still) and hoses were open for a while... 2nd error. (added a new dryer filter at least).

Air and moisture definitely entered the system while it was open, but a thorough evacuation before recharging the system would've eliminated those. Sounds to me like evacuation wasn't done, unfortunately. So you still have air and moisture in the system, even though you replaced the receiver/dryer (R/D), which will remove some of the moisture (until the desiccant becomes saturated), but not air.

Disassembling the compressor, solvent cleaning only the case but not the piston assembly, probably was okay as long as you blew-out and dried any remaining solvent beforehand. This presumes that you didn't introduce any dirt or grit into the compressor on reassembly.

Did you also replace the shaft seal while you had the compressor apart? If not, the seal might leak at some point in the future.

jm_vectrab wrote: Sun Dec 07, 2025 5:55 am What is the best way to remove oil without disassembling everything again now? if the shop pulls vacuum from the high pressure/liquid side, will it work? I can also remove the fill bolt in the compressor and use a syringe to remove most in the sump there...

If the shop recovers and evacuates the system now, *some* oil will come out, but only a small amount.

Here's what I recommend that you do: Have the shop recover the refrigerant, disconnect and remove the compressor from the vehicle, unscrew the drain plug, invert the compressor, and let the oil drain-out overnight into a graduated container. Hopefully, you will have drained-out 4 or 5 ounces. Next, replace the PAG-46 you drain out with the identical amount of PAG-150. Then replace the R/D again, evacuate, and recharge the system to specs (or have the shop do it). Whatever small amount of PAG-46 that remains in the system will mix with the PAG-150 on running the system for the first time. In my humble opinion, running the system containing this small amount of PAG-46 won't hurt anything.

jm_vectrab wrote: Sun Dec 07, 2025 5:55 am Also by researching this, found some saying that running too much/deep vacuum can boil the oil and damage seals, is that true? I refreshed most things and don't want to put at risk... just not sure how it is possible/works.

I have never heard of or experienced that happening. But I would replace all of the o-rings and gaskets in the system while you have it apart.

Oil these days really depends on the compressor manufacturer. So many people selling different brands that fit vehicles claim they are OEM "Replacements", especially your eBay/Amazon shoppers. Some overseas compressors use PAG46 even though the OEM was something else. That's why you should verify with the seller what to use. It might fit the vehicle, but is it an OEM compressor?

Thanks John,

Yes I took the compressor apart and replaced the seals, fine grid sandpaper to clean the shaft and guide to not damage it. It was in fact one the main sources of leakage.. also replaced both hoses that leaves the compressor, the exp valve, dryer filter, and tower valve. removed the evaporator to check for leaks (was all dry) and cleaned it + the air box (was disgusting, full of leaves and dirt/hair there). I also bought a set of o-rings and replaced everything I touched.

Regarding the car model its indeed from Europe and SA only, that info was on the compressor so I know its correct: 7.5oz of synthetic oil SAE J639 --I still haven't found the "translation" for J639, searching specifies PAG150. The sticker on the car calls for 900g of refrigerant.

Yeah I see now.. the guy in the shop didn't vacuum thoroughly... it was rough 10min not even using a machine, it was like a homemade motor pump... I will take to a decent shop next time.

Interesting is that GM supersedes this PAG150 with PAG46... probably because just a few might remain with this old compressor and most new ones call for 46... also asked another shop and the guy said to use PAG100... they don't seem to care too much... I will stick with 150 that OE calls for.

I am just debating in what to do now, your recommendation is perfect but I don't want to lose more time and stress with it... I was thinking in just bring to the shop and ask them to recover; vacuum on both ports, then open the side oil sump plug on the compressor and use a syringe to drain all oil possible through there, add what I removed in PAG150, vacuum again for an hour or more, add refrigerant and see how it does. what do you think about it?
---*as I said it seems to be cooling fine right now, I am just not using until I fix this wrong oil mistake.

in the end of the day my system is definitely not perfect, it was leaking and without refrigerant/use for years... I revived for cheap just to get by, the correct thing here would be to replace everything... I could see sludge inside the hoses when disassembling, it was like a dry mix of oil and refrigerant idk how to describe but will share pics below so you have an idea...

*I might end doing what you said though, it will stick in my mind to do the right thing

@Tim just saw you post, yes I mentioned above it still OEM compressor from 99 that came in the car, its a Harrison/delphi V5 and the sticker calls for --7.5oz of synthetic oil SAE J639 --searching returns PAG150 but I didn't find a apples to apples comparison and discovered GM superseded it with PAG46...

*using this post to add the rest of the pictures sicne the forum limtis the amount.