96 regal 3.8L (Custom) AC system specs

jay foley
10-12-2015, 03:01 PM
I need to know what kind of numbers I should expect to see on a gauge set...once hooked up to my car's AC system. I suspect that the system has leaked Freon...and could simply add 12 ounces of Freon to the system..but I don't want to damage anything by doing so. The mechanic who replaced the compressor just 2 weeks ago...is cocksure that the problem has to do with the "blend damper" that's buried behind my dash...but I don't agree. The diminished amount of cold air coming out of the dash...was a gradual diminishing over a day and a half's amount of time. If the blend damper was the issue...I'd expect that there would have been no "gradual" diminishing of cold air...(either the damper door is stuck...or it isn't). In short...I want to get to the bottom of this problem in a systematic way...(BEFORE bringing the car back to him and getting into an adversarial "pissin' match" with him). If I throw a can (12 oz) of R-134 in it...and I suddenly get cold air...(even if just for a few minutes)...I can then KNOW that the problem doesn't have anything to do with the (complex) "blend damper" or "main controller" that has all the vacuum tubes going in to it. I can take my car to work and have a guy put a gauge set on it...but in talking to him this morning...he said he needs to know the correct pressures (numbers) that should show on his gauge set. If it shows that theres a diminished amount if Freon in the system....then I DO plan on putting a can of R-134 in it...via the Schrader valve....and see what comes out of the dash.

10-12-2015, 06:14 PM
Your car uses a V-5 compressor- number one failure mode for that unit is leak through the shaft seal and compressor body (belly) o-rings- if you have added dye- you should see green all around and under compressor- as well as it being slung out from in between pulley and clutch driver-- is front of compressor wet?

Any numbers we give you are totally variable- and basically not able to determine anything- you have a variable compressor that will run with as little as 5% of factory specified weighed in refrigerant charge. Your system does not cycle like a fixed displacement compressor when it gets low on refrigerant.

Since it gets cold when gas is added- I agree with you, the doors are okay- but you have a massive refrigerant leak- I rebuild those V-5's (re-seal) all the time- I buy the re-seal kits off the Bay- and clean all the sealing surfaces and install a new double lip seal and get another 15 years out of the compressor...I've probably done over a thousand re-seal V-5s like yours- everytime the leak is the shaft seal and the belly o-rings...so I'm playing the odds yours is the same....

I see now, you say you replaced the compressor- was it new? if used all above still applies... if new or rebuilt, you probably have a leak somewhere else in the system.

If you need to know for sure if you have a leak - have all your refrigerant recovered and weighed- and compared to factory spec 2.2 lbs as I recall ( it is on underhood label on shock tower on your W-car...

jay foley
10-12-2015, 06:37 PM
I appreciate your response...and can tell that you really "know your stuff". I need to get outside and try the gauges at this point in time...(have a short window to do this before my work buddy has to go home). I have more info to impart...but need to wait till I get the testing with the gauges out of the way...first.

jay foley
10-12-2015, 09:10 PM
I hooked up one of those cheap delivery hose / PSI gauges that comes with those tall bottles of "NASA approved" synthetic Freon...(co-worker had one in his truck)...did the procedure right...and the gauge never got into the green area. Even after adding a whole 12 oz. of R-134...the highest that needle got was right at the transition line from white to green. (IE...a 3rd of the "way up" the whole scale. I assume that since the specs say 32 oz. capacity that this AC system holds...that the system would hold the equivelant of 2 cans (24 oz)...and then 2/3rd of a can more (8 oz).

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