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-   -   air conditioner problems... (https://www.rx7club.com/1st-generation-specific-1979-1985-18/air-conditioner-problems-914463/)

ricerockettuner 07-23-10 09:57 PM

air conditioner problems...
 
i was going to gut the a/c stuff out of my car but i had to have my dash apart to fix a few things.... i got the blower blowing again so i figured what the hey. i threw a belt back on the compressor and recharged the system and it worked great for about 3 days. but im pretty sure the freon leaked out being that theres no telling the last time this a/c has been ran. how are these cars setup? its an 82 so does it have an oriface tube? idk if i spelled that right but im not too keen on a/c work other than the basics. im pretty sure the compressor is good so is there any o ring kits i can buy to change them all out in the system? and what else would i need to buy hardware wise to get it all working again properly? like i said it cooled great for like 3 days so im sure the compressor is good

Rx-7Doctor 07-23-10 10:35 PM

If if cooled well for 3 days and now it is not working then you have a leak in the system. You can either get some leak detector then find the leak (s) and fix them or take it into to a good A/C shop and let them find the leak then perform the repairs yourself.

There is no "orifice" tube.

You can get a O-ring kit form Rock Auto but it does not say what is in the kit. It's highly unlikely that you have a bad A/C hose but possible. There is also the A/c condenser and evaporator cores that could be leaking. That is why it is important to determine if and where a leak may be first.

What did you recharge the system with?

There is also the possibility of a electrical failure that is preventing power from getting to the compressor also.

DarrenTRS 07-23-10 11:19 PM


Originally Posted by Rx-7Doctor (Post 10126429)
There is no "orifice" tube..

I believe he's asking if the a/c system is a Fixed Orfice Tube or if its a Thermostatic Expansion Valve but I would assume it's an Orfice Tube system aka Expansion Valve.

Unless you have gauges attached to the system unfortunately it's very hard to simply say outright what the problem could be but hopefully I can help give you some basic things to look for.

1. Check all hose connections for wet/grimy/shiny, refrigerant evaporates but the oil can leave behind a residue and that's always a great clue that you are leaking.

2. Check to make sure the compressor is engaging, ESPECIALLY if you've been working on the system as a hole sometimes people simply don't reconnect a connector all the way or something wiggles lose and it could be as simple as that.

3. If you have gauges, hook them up first thing in the morning and get a static reading, if you used 134a and the system is full and properly sealed you should read about 1psi per degree of ambient temperature.

4. If you have very low pressure the receiver/drier should have a pressure switch inside of it that will automatically shut off the compressor to protect it from damage i.e. lack of refrigerant and oil. [another clue that you may be leaking].

5. If all else fails, take it to a certified a/c technician and have him do a diagnosis, chances are he will look at these things again but he can check both static pressure and go ahead and recover whatever is in there to see if anything was lost.

I'm also a very very firm believer that if you do decide to retrofit the system that you have it professionally evacuated, cleaned, tested and then charged to make sure no problems occur because bad things happen when R-12 and 134a mix more specifically the oils [unless mineral oil is used which is compatable with both] that each use can lead to problems of your own but if a shop decides to work on your a/c system and they don't use a gas identifier and they accidentally recover a mix of R-12 and 134a into a system purely for 134a or R-12, that entire machine becomes completely useless until it has been sent out and cleaned itself which is by no means cheap.

Good read/tips on retrofitting R-12 to 134a http://www.aa1car.com/library/retrofit.htm

ricerockettuner 07-24-10 12:04 AM

yall have been helpful. the system was already changed to 134a and had a sticker on the compressor and hood that stated so. u answered my question about the oriface tube. i couldnt remember the name of the other thing that my dad told me it might be but i think its the other thing u said. we had gauges hooked up and it seemed to have a very small amount of pressure to start off with and not completely leaked out. we added almost 2 small cans and it was cooling really well. im guessing that it is a leak since it worked for 3 days but i havent hooked the gauges back up yet. i ordered the oring kit and the dryer from rock auto and spent 27$ so its not that bad if i dont need it. ill try to look for oily residue on the connections tomorrow and see what i can find. any suggestions for what to buy to detect the leak if i dont find it this way? i think ive seen that stuff that is ultraviolet or whatever that shows up with the special light to detect leaks.. is it worth buying?

Stevan 07-25-10 11:55 AM

Get the cheap uv kit with the pen uv flash light, and a can of 134a with the dye.
The most common leak is the shaft seal on the compressor. After you put the dye in and run it for some time, make sure that you check the bottom side of the comp for oil/dye.

The system uses a thermostatic expansion valve(txv) not aka a fixed orifice tube(fot).

Mineral oil is not compatible 134a, mineral oil is what is originally in the system. There is no reaction when 134a is mixed with mineral oil, they're just not miscible, meaning the 134a will not carry the oil through the system as the refrigerant is intended to do.
Ester oil is compatible with r-12, and 134a. It is now what the retro kits contain.
PAG oil is compatible with 134a, but not r-12, PAG oil is what the retro kits used to contain. There is a bad reaction with PAG oil and r-12, or even residual r-12.
There is no reaction between 134a, and r-12, it's just illegal mix them for other reasons.

ricerockettuner 07-25-10 09:51 PM

very good info.. i ordered the dryer and all the orings and stuff to change them all out incase one is leaking. but i will get some of the uv stuff first to look and see if i can find the leak when im off work thursday


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