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Discussion Starter #1
My air in the car I noticed quit cooling, I noticed too that the clutch kept kicking in and out. Figured it was low on freon. Anyway I bought some AC PRO freon and noticed I wasnt making any head way with that. I put only 7oz in it now the needle went in red zone on can. Clutch still in and out. Any ideas?

1995 Thunderbird
 

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It'll do that overcharged, too.

You need a set of gages on it to tell; they're easy to overcharge just adding it in, I've done that.
 

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There are a couple things I can think of off the bat, but Grog is right - you really should get a set of gauges with both low and high side hookups to see what's going on.

"Red zone" on the can - what do you mean by that? Pressure too low or too high?

The clutch will engage when approx. 40 PSI or higher is measured by the cycling switch on the accumulator (by the firewall, where you were connected to charge). If it drops below ~20-25 PSI, it will disengage the compressor. As far as the clutch, it's normal for it to cycle like that, depending on temperature/humidity/AC settings.
 

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Discussion Starter #4
Man I hate taking my bird anywhere, no gauges. On the can it fluctuates from low to green with clutch kicking in and out. With just can guage hooked up without can its in red. I dont see how its overcharged when I only put 7oz in it.
 

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Discussion Starter #5
The clutch kicks in and out like every 3 seconds. Could it be something else besides freon?
 

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(Semantics only) Freon is R-12, your car uses R-134a. :)

In any case, if it's cycling rapidly it's either a clogged orifice tube and/or low charge. The only way to know is to see high side pressure simultaneously with low side pressure. If the orifice tube is clogged that usually means something more sinister is going on... (compressor dying)
 

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Discussion Starter #7 (Edited)
Ya know I have worked on vehicles alot in my life and never had to mess with AC. Where is the ori
fice tube? Thought I might add the rpms go up and down also.
 

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Man I hate taking my bird anywhere, no gauges. On the can it fluctuates from low to green with clutch kicking in and out. With just can guage hooked up without can its in red. I dont see how its overcharged when I only put 7oz in it.
OFF pressure will be about 70psi or so; that's static for R134a.

ON at 70PSI is WWWWAAAYYYYY overcharged; OFF, it's perfectly normal.

That's why you use both gauges, and study up on what the numbers mean.

RwP
 

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Ya know I have worked on vehicles alot in my life and never had to mess with AC. Where is the ori
fice tube?
The orifice tube is in the liquid line, right past where it connects to the condensor.

Liquid line looks like this picture:


That little crimp there on the metal part is the cold side of the orifice tube; the open end goes to the condensor.

BTW - Do NOT OPEN THE SYSTEM WITHOUT PROPER TOOLS!

If you're lucky, you'll just vent the R134a into the atmosphere.

If you're really unlucky, well, tell us first what kind of funeral you want after you freeze your lungs or suffocate (not impossible; rare, true, but NOT impossible!)

RwP
 

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I think the lady at Autozone said the original capacity was 31oz for my 1992 LX. I ended up using three 12oz cans last week, first two with sealant and should have put one with die in first.


The compressor did not cycle after the first can and I got your red zone reading on the low side. I figured the compressor needs to cycle to get the coolant to the high side. My low budget choices were to add more or look for the AC delete pulley. Several Utube videos told the gauge should only be read when the compressor is working.


I drove the car for and hour to move sealant around. I'm ready for the one week road test now.


I'm no pro but I saw a bunch of AC tools available for borrowing at Autozone to do this right.


I found a small UV flashlight at ACE hardware that might work with the die. It was $10.
 

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Sealant.

Well, it was nice knowing your wallet.

Sealant has a bad habit of sealing up the condensor, the evaporator, and the orifice tube completely.

TWO cans?

Hate to say this, but you wasted the money there.

If it's a 1992, like your SIG says, you probably need new lines anyway (they're old, and possibly starting to seep R134a which is smaller than R12 ), a new accumulator, a new condensor, and a new evaporator to go with the new compressor.

*ponders*

I'm laying out about $350 to do my Dakota, but it's a bit pricier than the Cougar for all but the compressor.

And that's with a fairly new condensor and evaporator; the high pressure hose broke at a weld and dumped all the oil on me.

RwP
 

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Discussion Starter #12
Well a friend has some guages so I'll be testing the system, fire up some youtube videos. I'll report back when I get it solved or have more questions, thanks guys.
 

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Hi Ralph I paid to have everything but the compressor replaced three years ago. They gave a 1-year guarantee. I got a new crack in the dash for free too. The shop owner blew up my old lines with his machine while I was standing there bs'ing with him. Kinda scary and I thought he earned a knuckle sandwich and not my check. He broke some vacuum lines too and wasn't around when I picked up the car.

Anyway, the one week road test went ok. I'll be shopping for a seal kit and pricing compressors and will run the die through it if it all leaks out. I need to check if Autozone has a vacuum pump they loan out.

I didn't read the 134A cans too closely and did not see mention of oil coming with the 134A in the cans. I thought they did come with some oil but I haven't read or worried about AC in three years.
 

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Discussion Starter #14 (Edited)
well before I went an picked up gauges I thought I would mess some more. Hooked up the AC Pro can again guage moving back and forth from 20psi to 44psi with clutch fluctuating on compressor. Two things, it wasnt taking any liquid out of the can and highline had moisture all on the outside of it. Does this mean the orfice tube plugged up from not taking fluid?
 

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Discussion Starter #15
well before I went an picked up gauges I thought I would mess some more. Hooked up the AC Pro can again guage moving back and forth from 20psi to 44psi with clutch fluctuating on compressor. Two things, it wasnt taking any liquid out of the can and highline had moisture all on the outside of it. Does this mean the orfice tube plugged up from not taking fluid?

Im thinking orifice is plugged up maybe because both lines are not cool to the touch plus fluid wont go in system. This something I should take car in or DIY job?
 

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I'd take the car in.

For the pressure fluctuation - of COURSE it's fluctuating! Compressor runs, low side drops below the switch point, compressor cuts off, pressure starts to built.

It goes with how a refrigerant-based air conditioner works!

And *ahem* You really shouldn't be introducing LIQUID into the system; it should be gaseous where our injection port is. Or ports are.

RwP
 

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A little off topic here but was it a hard job removing the compressor?
I'm bringing home another victim and the a.c. is not working in it and I want to swap over the parts from one car to the other..
ANY tips would be very much appreciated .
 

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A little off topic here but was it a hard job removing the compressor?
I'm bringing home another victim and the a.c. is not working in it and I want to swap over the parts from one car to the other..
ANY tips would be very much appreciated .
It's putsy to get the AC compressor out, but not bad. If your sway bars are stock, no biggie. If the engines are out, total piece of cake.
 
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