I just installed a rebuilt GM A6 compressor, new barrier hoses, new expansion valve, new condenser, new dryer. All setup for R134. Retained the old evaporator. I added 10oz of PAG100 directly into the sump of the A6 compressor, and didn't add PAG anywhere else (I didn't know any better). Had an A/C shop vacuum the system then add R134, 3.7lbs.

When the A/C was turned on 65d setting full on, and the A6 clutch picked it blew out the rear big O ring between the cylinder housing and the rear housing plate on the A6. So... a couple of questions:

Do you think I hydrolocked the A6? Should I have put the PAG into different parts of the system? Did I use the right PAG oil? Did I use too much PAG oil? Too much R134?


I plan to just replace the O ring on the A6 with a new one (I have the O ring kit). I will flush the condenser, the evaporator, and the hoses. I will flush out the A6 with PAG oil while it's apart. Maybe squirt the expansion valve a bit with brake cleaner while I have it off to access the evaporator flush? I ordered a new dryer, just for kicks.

Thoughts? Suggestions? Encouragement?

 

For the Series III cars, at least, Jaguar manuals say 7 ounces of oil when replacing the compressor. Almost everywhere else you check, though, the norm seems to be 10 ounces for the A6

I'm not sure why the difference, or if excessive oil accounts for your problem. My gut feeling is 'no' but my ut has been wrong before

Cheers
DD

 

6 to 7 ounces, not 10. Because at least 1 ounce will remain in the system even after evacuation.

the label in the picture reads "CHARGE R12", you might have purchased the wrong compressor for R134A, which works under a higher pressure.

 

Do I scatter it around? 2 oz in condenser, 1 in dryer, 2 in evaporator, rest in compressor?

 

he he, NO ! you just put the 6 to 7 measured ounces into the compressor before mounting it to the engine block. That's all you put in the system, nowhere else. You also need a compressor that works with R134A.

I take it you evacuated the system for at least 1 hour, right? If not, your system was full of air.

 

Jaguar's recommendation for the Harrison A6 compressor and retrofitting the R12 system.

bob

 

The way I read the service bulletin is that the Harrison (GM A6) compressors are compatible with both R12 and R134. Am I missing something?

 

Sounds like the system got "slugged" with too much oil.
My advice: Take it to an ASE certified AC shop.

 

When converting from R12 to R134a you can only use 75% of the R12 amount.
3.75 pounds of R12 = 2.8 pounds of R134a.
Also if the system had mineral oil,(R12) it has to be flushed out completely as PAG is not compatible with mineral oil.
If you are not flushing the system, you have to use ESTER oil which is compatible with mineral oil.
Only use green o-rings for R134a.
Total amount of oilwith system totally empty = 7 ozs.
Total amount of R134a = 2.8 lbs.
On my conversion from R12 to R134a I used 6 ozs of Ester oil and 2.4 lbs of R134a and its COLD

 

Good info-as usual Sanchez - wish I knew that before blowing the rear seal out of my GM A6 compressor. Live and learn. I now plan on flushing the system. There was R134 with the old compressor, so I'll assume no R12 after all this time. The rebuilt compressor I bought only spent about 2 minutes of "compressing" time before I shut it down. It was blowing cold air before I shut it down. When I pulled the rebuilt A6 off the car and dumped the oil out it, it was brown and I know I put clear 10oz of PAG 150 into it. It was new condenser, dryer, expansion valve and hoses at the time. This time, after replacing the rebuilt's rear O ring and "flushing" it out with repeated fillings of PAG 150 and turning the clutch by hand, I am doing a new dryer (just for kicks), true flushing of all hoses, condenser and evaporator. I'm hoping that the expansion valve (with only 2minutes of flow through it) is okay so I wasn't planning on new one there.

I'm hoping the blowing out of the O ring on the compressor was because I wasn't smart enough to cycle the oil by hand turning last time, and... that I put 10 oz in the sump. And that I just hydrolocked with super high pressure and blew out the O ring.

 

With these parts, you do not know how long they were sitting on the shelf before purchase. (Rust maybe)? If you are going to flush the system again, the auto parts stores sell an AC flush on a spray can.
One can will do the whole system. I used the AC flush rather than Acetone which causes the moisture in the air to convert to water. If using acetone, use compressed air to dry system immediately after flush. Any water/moisture in the system will mean a much longer evacuation time. If the system is totally free of moisture (very unlikely here in Florida) you need to pull a vacuum for at least 45 minutes. If you were closer to me I would lend you my AC equipment to DIY.

 

That's okay. Most of the stuff is cheap enough. I see a vacuum pump on ebay for $20 including shipping and a manifold gauge set at HF for $60. I'm shopping CL for a good used air compressor, as all I have is a "tire blower upper" now. And I need more for a A/C flush.