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Discussion Starter #1
this was the best place I could think to post this. Anyone use those do it yourself AC cans with the gauge on them? If so, would you recommend it or pay a shop? Also, if you had good experience, which brand did you use?
 

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this was the best place I could think to post this. Anyone use those do it yourself AC cans with the gauge on them? If so, would you recommend it or pay a shop? Also, if you had good experience, which brand did you use?
If you do not have the equipment to do it yourself, take it to a shop.
I have the necessary equipment (vacuum pump, scale, manifold, leak detector, nitrogen leak test setup) and do not care for the cans with the gauge on them.
 

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I have never used the type you are talking about. But harbor freight sells the manifold with the gauges pretty cheap. Just a thought. JR
 

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If it has not worked for a while, take it to a shop. How long ago did it stop cooling? If it's just a can low, that might work. I have not tried that gauge. I have a manifold. You most likely have a leak anyway, and unless your familiar with the system, your probably better off taking it. A/C is not complicated, but if the system is empty, you gotta fix the leak, pull the system into a vacuum for 30min, and fill the system back.
 

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I saw some of those cans at advance auto the other day. Looks like a neat solution for the do-it-yourselfer.

My question would be.. is there a direct replacement for R12 yet?

I'd like to recharge the AC on my chevette, but don't have the inclination to convert it to 134A. As I understand, I'd have to change the oil, any rubber seals, and swap out the orifice to make the swap.
 

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You can't just blow refrigerant into a discharged system. The system must be evacuated of all air before charging. At minimum, you'll need a vacuum pump and a set of A/C gauges.
By Federal law you aren't supposed to be working on the system without being EPA certified.
 

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I do mine own work.
I have a vac pump and a setup kinda like this...


Vac it out for an hour or 2, put in a can of oil charge them put in refrigerant.
 

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Discussion Starter #8
If you AREN'T supposed to be working on the system..

why are those recharge kits available all over the place? It still cools but the compressor cycles off and on a lot when I have it on the higher settings and the air coming out is cool but not cold. Id go into more detail of why I think this is how it was probably serviced in the first place but thats another story
 

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if it cycles then it's probable just low. Back when I was certified, you only needed to be certified for working on R12 system. Of course. when you become certified it's for both systems. You had to be certified to buy it. But again for R12. I would try one can, maybe two and call it a day. It's better if you have the gauges cause you could fill it according to pressure. But if it's cycling and your getting some cooling, your probably 8-12oz low. Just don't over fill it.
If you are gonna fill it, get some with dye so you could check for leaks when your ready to fix it. You could save a pretty penny.
 

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I tried kit from Kragen's this afternoon (mac 134).
The compressor was cycling off and on whenever the ac was turned on.
Hooked up the gauge and it shows the system cycling from 55 down to about 10.
Added the contents of the can and the system stopped cycling and the compressor stayed on. The gauge registered in the blue area which was 35-40 which was correct for the outside temperature.
Got in the truck and I will be damned if it wasn't cold.
For $25.00 I could not beat it. It would have cost me a minimum of $65.00 for a tech to tell me that plus the 134a. That was on my 1997 S10.
 

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Unless the system is empty, then no need to pull a vacuum. Only have to do that if there is air in there.

And quite honestly.. I sometimes wonder about the necessity of pulling a vacuum at all. Once, I swapped a compressor in a window unit ( R22 ) and totally forgot to pull a vacuum on the system. Totally. Dumped in a charge, filled it by 'frost line' method.. and it cooled fine. AND.. it never came back to the shop.
 

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If your system has air and moisture in it it needs to removed to prevent acid and sludge from forming inside of the system latter on.

If your system still has some pressure but is low enough it won't cool properly it most likely is ok to just add some more refrigerant.

If your system has no pressure you should find and repair the leak. Replace the receiver drier or accumulator drier, pull a vacuum and them recharge.

EarlyIIs
 

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Discussion Starter #15
It definitely cools

been high 70s low 80s and with the windows up, in my military uniform keeps me from sweating so Im sure I'll just do the at home recharge
 

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I tried kit from Kragen's this afternoon (mac 134).
The compressor was cycling off and on whenever the ac was turned on.
Hooked up the gauge and it shows the system cycling from 55 down to about 10.
Added the contents of the can and the system stopped cycling and the compressor stayed on. The gauge registered in the blue area which was 35-40 which was correct for the outside temperature.
Got in the truck and I will be damned if it wasn't cold.
For $25.00 I could not beat it. It would have cost me a minimum of $65.00 for a tech to tell me that plus the 134a. That was on my 1997 S10.
I have 1995 S-10 and have the same exact problem as you. the pressure cycling switch was changed in the past because it stopped working. but now it still goes on and off alot when the a/c is on so i assume its a little low. but i did notice that its all dirty and wet where the pressure cycling switch is mounted, so i think its leaking there. i never put a new o-ring there. i got the switch at autozone for $15 and it didnt have a new ring. should i change the o-ring and then top off the A/C? or put a genuine GM cycling swithc first? also Wal-mart now sells a/c refill cans with a gauge and trigger switch on it so it can be saved and used later and it better than the old tap and use once design. anyone use this wal mart type yet? also what do you mean by "outside temperature" ? thanks
 

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Discussion Starter #17
How much does a system hold?

I just emptied a bottle (18 oz) and it is colder but only went up about 2 on the gauge to 18
 

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how is the compressor cycling? If that gauge reads psi on the low side, you want to be at about 30, with outside temp about 85. How cold is it, do you have a thermostat on the vent? You might need another half a bottle or so.
 
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