A/c Not Getting Cold

On my 1989 Ford Thunderbird (3.8, 232 V6: not a SC or LX) I recently purchashed a rebuilt A/C compressor and new dryer, high pressure line and low pressure line. I took the car to a shop where I live, and they removed all my old parts. They used some spray to clean the system, vacummed out all the air and moisture, and installed all the new parts I mentioned. After charging the system with R12 refrigriant, the A/C got pretty cool for awhile. It got especially cool while driving as opposed to just idiling in park with the A/C running. But, about a couple weeks after I had the new A/C parts installed and charged, the A/C just doesnt get cold anymore. The compressor turns on, and it sounds normal, but the but cold air isnt coming out of the vents, even while driving. I'm thinking the rebuilt compressor could be the problem. But the funny thing is, the day before it stopped working, it was working fine. Can anyone out there please advise me on what could have caused this.

On my 1989 Ford Thunderbird (3.8, 232 V6: not a SC or LX) I recently purchashed a rebuilt A/C compressor and new dryer, high pressure line and low pressure line. I took the car to a shop where I live, and they removed all my old parts. They used some spray to clean the system, vacummed out all the air and moisture, and installed all the new parts I mentioned. After charging the system with R12 refrigriant, the A/C got pretty cool for awhile. It got especially cool while driving as opposed to just idiling in park with the A/C running. But, about a couple weeks after I had the new A/C parts installed and charged, the A/C just doesnt get cold anymore. The compressor turns on, and it sounds normal, but the but cold air isnt coming out of the vents, even while driving. I'm thinking the rebuilt compressor could be the problem. But the funny thing is, the day before it stopped working, it was working fine. Can anyone out there please advise me on what could have caused this.

I need a few questions answered before I can really help you.Do you have a clear sight glass at the reciever, or are there bubbles passing through? Does the suction line(low side) get cold near the compressor?
What pressures do you get on low and high side? @ about 1500 rpms the low should be at about 20-25psi/ high about 115-140 depending on ambient temp. (must be on max cool) I'm an a/c tech(non automotive) and it's been a while since I've played w/ r-12, but the pressures should be close to what I stated. Is the condenser clean? Help me help you. I need more info.

I need a few questions answered before I can really help you.Do you have a clear sight glass at the reciever, or are there bubbles passing through? Does the suction line(low side) get cold near the compressor?
What pressures do you get on low and high side? @ about 1500 rpms the low should be at about 20-25psi/ high about 115-140 depending on ambient temp. (must be on max cool) I'm an a/c tech(non automotive) and it's been a while since I've played w/ r-12, but the pressures should be close to what I stated. Is the condenser clean? Help me help you. I need more info.


Thanks E-bird for taking the time to reply to my thread. Unfortunatly for me I'm not sure I can answer the questions you asked me with any great detail. I'll try my best though. As far as the receiver is goes, I'm not really sure what you mean when you ask if I have a clear sight glass or bubbles. The receiver hose assembly I purchased is the Ready-Aire 3637 at (http://www.partsamerica.com/ProductDetail.aspx?mfrcode=EVP&mfrpartnumber=3637&parttype=397&ptset=A) if that helps any. The low side line does not get cold anymore. But when the A/C worked, the low side line got very cold. I dont know if this is normal, but the low side got cold, but at a certain point, the low side line was not cold. And as far as the pressure, the guy at the shop who did all the work for me said when he charged the system, it was at 40 psi on the low side and 130 psi on the high side. I dont know what the pressure is now. If you think I should, I try to find a pressure gauge to get that information for you. And, its hard to see the condensor on these birds. From what I can see it looks pretty clean. The guy who worked on my A/C said the flex fan I have on will not cool the condensor enough and if I put the factory fan and clutch fan back on the A/C will work better.
I hope I gave you enough information. I appreciate any theories you may have.
Thanks Again. I look forward to your expertise

I'm sorry for some mis-information. I was thinking that your age of bird had a reciever, but it doesnt. I had to check my Haynes book. It seems that your system may have a leak. Look for oil residue around all the connectors, especially the new connectors and at the back of the compressor. Or take it back to the folks that installed it. They should have a leak detector to find it, if that is the problem.

I'm sorry for some mis-information. I was thinking that your age of bird had a reciever, but it doesnt. I had to check my Haynes book. It seems that your system may have a leak. Look for oil residue around all the connectors, especially the new connectors and at the back of the compressor. Or take it back to the folks that installed it. They should have a leak detector to find it, if that is the problem.


Thanks again E-Bird. Your vast knowledge of A/C systems just reinforces my theory that I know very little when it comes to a cars air conditioning. I was thinking I may have purchased a defective compressor, considering its refurbished. I think you're right about those new connectors, because when my guy first installed the new high side line, and charged the system, the connector that goes to the inside of the car (not the side that connects the condensor) blew off. The mechanic said I didn't have the safety clips that Fords usually have. I went to Ford but they didnt have any listing for clips for AC connectors for my car. They did have them for a 1990 Thunderbird, which i purchased and have my mechanic put them on.

I just have a couple questions. Would it be normal for the new connectors to develop a leak of some type when the system held a vacuum for 30 minutes before it was charged??? And if the system does have a leak, would the compressor still turn on when the AC button is pressed??? Also, if a leak is the problem, would I have to get new lines, or new lock springs? Do you think I should unplug the compressor so it wont turn on until I get it fixed? And finally, do you think any oil residue will still be present even after driving the car for a couple days???

Once again, I greatly appreciate you taking the time to assist me. I hope one day I'll be in a position to assist you...

Thanks again E-Bird. Your vast knowledge of A/C systems just reinforces my theory that I know very little when it comes to a cars air conditioning. I was thinking I may have purchased a defective compressor, considering its refurbished. I think you're right about those new connectors, because when my guy first installed the new high side line, and charged the system, the connector that goes to the inside of the car (not the side that connects the condensor) blew off. The mechanic said I didn't have the safety clips that Fords usually have. I went to Ford but they didnt have any listing for clips for AC connectors for my car. They did have them for a 1990 Thunderbird, which i purchased and have my mechanic put them on.

I just have a couple questions. Would it be normal for the new connectors to develop a leak of some type when the system held a vacuum for 30 minutes before it was charged??? And if the system does have a leak, would the compressor still turn on when the AC button is pressed??? Also, if a leak is the problem, would I have to get new lines, or new lock springs? Do you think I should unplug the compressor so it wont turn on until I get it fixed? And finally, do you think any oil residue will still be present even after driving the car for a couple days???

Once again, I greatly appreciate you taking the time to assist me. I hope one day I'll be in a position to assist you...
A vacuum being held for a time is not a good indicator of a leak free system. Using nitrogen under a positive pressure for a time period would give better test results.
yes the compressor will still run if low on charge, but there is a low pressure switch that cycles the compressor under normal conditions, and will short cycle it when low. If system loses all of its charge, the same switch would keep it from running at all. Does it seem to cycle more rapidly now than when the low side line was cold?
Yes there should be some oil residue if it lost the amount to stop cooling as fast as it did in a short period of time that it did. It would seem that the leak is rather large. You can use soap/water solution(more soap than water) to check for leaks.