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Discussion Starter #1
Since I've gotten my 94 I noticed my a/c was warm. I've charged it once and it got cold for about a week then back to warm. I charged it again and it was blowing snow balls for about 3 days. Yesterday morning I filled the system with the UV dye and you guessed it back to cold again but now warm.,it will.be cold.for the first few minutes of being on then go warm. With the dye in the system i have not been able to detect any leak points and the only thing that is glowing back at me is the charging port on the low side tonite when it gets dark in will take my UV light and get underneath the a/c compressor to check the seal on it and see if I can get some dye from.that. any suggestions?
 

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Trying to diagnose A/C without the proper tools is ridiculous.

What are the high and low side pressures?

After we have that information, we can start to help with an accurate diagnosis.
 

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From my Experience, Can Charging a low system sucks, You usually wind up OVER CHARGING IT, and some people who I know who have done it, Also overcharged theirs ( I o/c mine by 5oz once, Not horrible) Alot of those FANCY R-134a cans with the colorful labels and the charging hose with the gauge have crap additives in it, opposed to the USA (not Chinese like walmart sells) 12oz R-134a cans.

You probably have a leak, Or you could of overcharged the system and (could of) cooked the compressor. The System on these cars is kinda on the small side, 1lb 12oz, so its easy to put too much in.

Check the Service valves for leaks (Remove the caps on both the high and loe side) Check every switch connection, O ring connections, Condenser, And the compressor, (shaft seal and check the case seals) Yea the Evaporator could leak too, PITA to get to that w/o major disassembly.
 

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Both replies are correct. People refuse to believe this advice because there will always be someone who will disagree "I have been working on my own A/C with charge kits for 20 years and have no problems." You can bank on one of those posts coming soon. The O/P will take this as validation of what he wants to hear and will ignore our advice.
 

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Both replies are correct. People refuse to believe this advice because there will always be someone who will disagree "I have been working on my own A/C with charge kits for 20 years and have no problems." You can bank on one of those posts coming soon. The O/P will take this as validation of what he wants to hear and will ignore our advice.
I find this is even true when I offer for them to drive over 15-20 minutes to my house so I can throw the gauges on and see what it's doing. They never seem to have time for this then end up paying a shop top $ to get it going again. I own two sets of gauges the vacuum pump and a 30 pound can of R134 made in the USA that I can sell them at $5 per 12oz so I have everything but the hard parts to get someone going.
 

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Discussion Starter #6
Well I think I've pinpointed my leak, from the high side valve, I took the cap off and noticed the dye I had put in yesterday morning around the center and around the metal ring of the high side valve and bubbling up and the center. I've heard there were some brass upgraded valves for the high side. Also I'd want to do the low side valve as well. I figure if one is going the other shouldn't be too far behind.
 

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Discussion Starter #7
Both replies are correct. People refuse to believe this advice because there will always be someone who will disagree "I have been working on my own A/C with charge kits for 20 years and have no problems." You can bank on one of those posts coming soon. The O/P will take this as validation of what he wants to hear and will ignore our advice.
I find this is even true when I offer for them to drive over 15-20 minutes to my house so I can throw the gauges on and see what it's doing. They never seem to have time for this then end up paying a shop top $ to get it going again. I own two sets of gauges the vacuum pump and a 30 pound can of R134 made in the USA that I can sell them at $5 per 12oz so I have everything but the hard parts to get someone going.

Man if your in Maryland you let me know time and place lol. I'm trying to avoid shops
Last time I took.my car to a shop I got screwed royally, which led me to buy my caprice lol
 

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Discussion Starter #8
Can someone point me in the right direction to get a better grade high side and low side valve?
 

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Sorry I'm in Dayton Ohio. As far as the valve goes the one Oreilly gave me had another plastic ball in it like the factory and leaked brand new. I got a new set of hoses which uses the Schroeder valve instead of the ball. I was replacing the compressor anyway. Plus check your hoses since they rub on the A arm you might see it's almost worn though and you need hoses anyway.
 

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Discussion Starter #10
Sorry I'm in Dayton Ohio. As far as the valve goes the one Oreilly gave me had another plastic ball in it like the factory and leaked brand new. I got a new set of hoses which uses the Schroeder valve instead of the ball. I was replacing the compressor anyway. Plus check your hoses since they rub on the A arm you might see it's almost worn though and you need hoses anyway.
Is it a must I get the new hoses and not just the valve?
 

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Believe the valve is part of the hard-line section of the A/C hose(s)...
 

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Basically yes,but I would much prefer AC Delco hoses/lines....
 

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Discussion Starter #15
still doing my searching making sure I have no other leaks in the system, today I found the accumulator is oily and glowing green from the dye like it's leaking out of the low side port as well...:mad:. so in this instance should I look to replace this accumulator as well as my high side port?
 

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From my understanding yes. Wherever you see any dye under a UV light is where you want to concentrate on making the repairs. Make sure you flow the lines everywhere and from every direction. Don't be upset. You're working on a 20+ year old system on a 20+ year old car. The fact that you're finding these leaks means you can have a cooler/longer lasting system.
 

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The time you will spend hunting down leaks could also be spent replacing every O ring, a kit for our cars runs about $6 and its money well spent to keep the system running longer when you do get it sealed up
 

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Discussion Starter #18
The time you will spend hunting down leaks could also be spent replacing every O ring, a kit for our cars runs about $6 and its money well spent to keep the system running longer when you do get it sealed up
I honestly wouldn't know where those o rings go to tell you the truth. as far as swapping the accumulator is there any special precautions I need to take or is it just unbolt and swap?
 

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I honestly wouldn't know where those o rings go to tell you the truth. as far as swapping the accumulator is there any special precautions I need to take or is it just unbolt and swap?
The O-Rings go at each connection where you see fittings.

Starting at the front of the car:

  • Condenser, 1 line going in & 1 coming out, next to the battery.
  • Accumulator AKA: Receiver/Dryer, 2 lines
  • Evaporator Core (@ Firewall), 2 lines
No special requirements regarding the accumulator, except the fact that you do not want to leave the ports with the new dustcaps uncovered for long. There is a desiccant bag inside which absorbs moisture, and if the accumulator were to sit around and breath ambient air, it would render it useless.
 

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If you take anything apart, replace the O-rings. Trivial cost when you have something disconnected. O-rings should not be installed dry ... use some compressor oil.

If you do replace the lines, replace the orifice valve. Again, trivial cost when you have the hoses out (orifice valve is in the hose as it runs by the battery). Stuck inside the piece that attaches to the A/C radiator. If you see metal pieces trapped in the orifice ... you might as well replace the compressor while you are all open.

You can replace just the valves. They will unscrew from the hoses (O-rings there as well). These are aluminum couplings and can sometimes seam incredibly tight ... just aluminum oxide ruining your day. Lord don't do this with Freon or pressure in the system.

If you replace the dryer, remember to put compressor oil in the dryer. I forget how much goes there. It's in the FSM.

You can take a typical vacuum gauge (pressure gauge) and hold it over the H/L valves. Make a decent seal by hand. If the gauge rises ... it's leaking. It should not rise at all. Sometimes you can take a small drift punch (flat on the end) and tap the Schrader valve (L) a couple of times or the little ball (H) a couple of times and it will seal itself after blowing out a touch ... just some dirt in the way, etc, etc. I say sometimes. And DON'T do this till the pressure equalizes (engine OFF). And wear safety glasses at all times.

Good luck.
 
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