A/C question for you all???
 

Hi again,
My A/C wasn't cold enough, i converted to R134a when i replaced the low side line. Now it still wasn't to my likeing. I drained the system again and put a real set of guages on it, added the 2.42 pounds of R134a in it. It got to around 50 degrees, not cold enough, so i wanted to try the orifice tube thinking maybe it is dirty. Alldata says that it's in the high side line nearest the battery. I once again recycled the system, no vacuum, and low and behold i couldn't find the old orifice tube. It just plain wasn't there. I put the new one in and put the system back together. The car will only get to 50 degree's still.
Do you guys think that this system needs to be vacuumed? Is the orifice tube in another line somewhere? Or maybe someone just took the old one out and never replaced it.

My reading's:
Ambiant temp: 90 degree's
High side: 250
Low side: 40

Thanks,
Sellncars

You do relize that when you convert from r12 to r134a your system will not run as cold.Car that originial have r134a general have higher compression compressor.

Also, keep in mind that A/C is not designed to keep the car like a meat locker. Air conditioning was designed to keep the ambient difference in temperature of only 20 degrees. However, most think it should be much greater.

Re: A/C question for you all???
 

Your pressures sound about right and 50 degree duct tempurature in 90 ambient temps are also right, but you should always vacuum the system down after it has been opened to atmospere.

I know it wont get as cold as R12, but it will get colder then these temps. How many of the mechanics on this board actually vacuum the system? I understand that when you take a part off of the A/C system that you will get air in it. The air in the system cant be good.

Thanks,
Sellncars

Well i do beleive when your chargining the system and u take the connector off air can;t find its way in because of the pressure of freeon. It would not permit air in for that one second. I have a question for anyones a/c that works does your compressor kick on and off in even intervals? I know it is semi working the air is cool but not yet cold i would like to get it colder. Thx for the input

It's not air in the system that causes a problem. A vacuum is pulled to remove the moisture from the system. The moisture in the air is what can't mix with the freon.

You are correct, when you take the connector off to charge the system you wont get air in the system. Now in my case i had to take a line off and replace it, air had to get in the syatem, even though it was sealed until i got the line home to install.

Thanks,
Sellncars

Correct, you won't get air in the system when you remove the connector. Don't forget to "burp" the air out of the hose before opening the valve to the system.

Yes, the compressor cycling on and off is normal. Simple explanaition is, there is a tempurature sensor in the line (low side I think). When line temp gets below something like 35 it disables the compressor. Then when line temp gets above something like 40 it enables it again. Hence the cycling.

This whole problem started when i had a broken low pressure line. I went to the salvage yard and got another line, installed it, charged the system and it has never been that cold since then. Now my clutch never turns on and off, it's just always on. I just bought a vacuum and a real set of gauges and am awaiting to get them. Then i will start fromn scratch and do it right. Hopefully it runs colder when I'm finished.

Thanks,
Sellncars