The ac compressor in my 01 needs replacement. I plan on swapping part for part. Are the ac lines under pressure? Once the new part is in what are the next steps? I plan to bring the car to a local shop to have system re-charged. I have heard that if a comprssor change is done that the system needs to be evacuated, recharged and the collector should also be change due to moisture and debree in it. Never did ac work. Am I missing anything. Thanks, Paul.

 

I've heard the same thing. I need to change my compressor when I get back from Iraq. I'll put in a can of R12 to make sure it's holding pressure, then it's off the shop for evacuate, oil and recharge.

 

Unless your a/c system has been "open" to the atmosphere you may not need to change out the collector. There will be pressure in your system if it is not open to the air so be careful. If there is pressure, that is a good sign. Assuming this is the case, get the system evacuated the day you put in the new compressor and you may not need to change out the collector/drier.

Why are you (both of you) sure you need new compressors?
Also, jjcslynn, I'm sure you meant to say R314a. And good luck in Iraq.
verysoon

 

It depends on what went wrong with your compressor. If there is debris in the system such as metal shavings it shoud be flushed out, as well as changing the orifice tube, and the acummulator\drier. If this is not done the new compressor will most likely be destroyed as well. After you do this then you can bring it to tour shop to have it evacuated and recharged.

 

jj...Let me start out by boldly saying that I speak for All of us at this forum...Please be safe and come home soon from Iraq!! That being said....

Verysoon....Aren't I opening up the system to the atmosphere and depressureizing it as soon as I change compressors?

gamisou.....The reason I am changing compressors is that the clutch assembly is making a metal to metal grinding noise. (When system is turned on the noise stops.) I can get a new GM clutch/pulley assembly however, I do not have the removal tool and to change the clutch I will probably have to remove compressor anyway. To purchase the clutch and tool will be more $ than a remanned compressor.

 

Yes, when you remove the compressor you have"opened up" the system. As long as you evacuate the system in short order, like a few hours, your accumulator/drier should not be affected.
Sounds like your system is "closed" right now and in good shape other than the clutch assembly.
Read your manual carefully. Bleeding off a fully charged system must be done with care as the freon will give you frostbite if it contacts your skin. I would be tempted to re-examine your options on the clutch assembly. If you can replace it without removing the compressor that would be the ticket.
g

 

Gottcha.

 

Yeah I meant the R314A. It's the only stuff you can buy over the counter. I started off with a bad evaporator, changed it, then found my AC compressor was leaking at the body. I have a new orifice to put in, but should I change the dryer too?
I've dropped a small fortune on the AC so far. I'm about to give up, but I could be moving to Florida next year and I'll want it.

Thanks for comments concerning my safety. It's weird, but you can become complaicent about rocket and mortar attacks. I've been lucky, so far the closest ones have only landed about 100 yards away.

 

jjcslynn

yep. sounds like your system has been opened up quite a bit so the drier has probably soaked up enough water to not function properly.
Oh yeah, the best way to check if your system is properly closed is, after you hook up all your parts you pull a deep vacuum on it and see if it holds that number for at least 8 hours. If so, you are good to recharge. Don't forget the oil if your compressor does not come with oil pre-installed.

please keep your head down!

g

 

im worried about my AC compressor. My car makes a "ticking" noise when the AC is on, (from the front of the engine), everyone thinks its a leak in the exhaust, however, when i turn off the AC, the sound immediatly stops. I talked to a dealer (on the phone) and they said that that is an indication that the compressor is on its last breath.... Is this true? The AC blows cold and fine, but the ticking noise (you cant hear it from inside the car) is worrying me.
What should I do?
Should i look from cheap slightly used compressors in the case it dies? or should i just wait and see what happens?

Thanks,
Dan

 

red

Not attempting to be an a/c guru, but i've fooled with it a bit on cars and boat reefers.
It is so difficult to find an honest a/c guy is why I started learning about it on cars. They all, well most, seem to want to replace everything before trouble shooting first. I had 3 places tell me I had to replace the whole system in my 280zx a few years ago. I lived without it and finally stopped by a guy that had worked on a/c for a friend. He checked it out after I gave him carte blanche to fix it at whatever cost.

The noise my compressor was making was a LOUD ticking. He pulled a vacuum. It held. He put in a full shot of oil (3 ounces)(plus new freon, 2 cans) and it works great! (He charged 50 bucks, not the $1200 I was quoted at every other place.) The system has never been opened in 25 years now.
Explanation is "the compressor oil breaks down after a number of years", yours is now 9 years old? May just need a shot of oil. Definitely worth a try.
Let me know if it works. It is always the last resort to crack open the system and start replacing stuff I have learned.
sorry for the long post. thought some background might help.
verysoon

 

I agree the last resort should be opening the system. I have had dismal experience with systems that have parts replaced and getting them to work as well as before they are opened. If you have a good system now and check its performance with a thermometer you will find it works better than the repair spec that GM says a repaired unit should meet. Most new car A/C units at engine idle will run about 37 to 38 degrees at the outlet while the repaired ones run at 42 to 43 degrees. That 4 to 5 degrees difference in outlet temp makes all the difference in the system cooling you or not cooling you.
Bill

 

im not an expert at all with AC stuff....what does "he pulled a vacuum" mean? Ive got a friend who is a mechanic, but not really a guru when it comes to AC stuff, will he be able to do this you think?

 

Yep, I know nothing about a/c. Verysoon...where/how does one put oil in an ac system??

 

also, what kind of oil is it?

 

Isn't it R134a?

 

Good Luck! I had a new compressor installed at the dealership. Cost me $1250.

But living in TX without AC is much worse than losing the $1250. I've actually been thankful.

 

The oil is special a/c oil called PAG oil, sold at any auto store. Diff cars take diff amounts of oil approx 4- 8 oz. check the serv manual. The 134a is the refrigerant (freon). To add oil the syst needs to be disconected, usually pour half into the compressor and half into the receiver/dryer ( the silver canister). Hook the system back together, attach the gages to the hi press and low press, the line from the gage set that would go to the freon bottle attaches to a vacuum pump and the syst is sucked down to 30in of mercury for at least 30 min. This removes all the moisture from the syst as water will boil and evaporate at that low pressure. Shut the pump, close all valves and let sit overnight to make sure syst holds the vacuum, no sense servicing a syst with expensive freon only to let it **** out from a bad connection. To back up, before adding oil, replace the parts that need replacing. If the comp took a dump the syst will be contaminated. At minimum the receiver/dryer should be changed as well as the orifice tube which is a small calibrated hole that the freon passes thru on its way to the evaporator(the radiator like device) that produces the cold air under the dashboard. The orifice tube is in the line usually where the line hooks to the evap and it has a screen on it to catch crap. Orifice tubes are only a couple of dollars. While the syst is all broken open all lines and condenssor need to be purged with alchohol or store bought products just for that purpose then blown clean with comp air or nitrogen. The evap will usually be clean because of the screen. Now that the syst is together and is leakfree add the approp amt of freon either by the # of ounces or by the pressure reading on the gages. Hope this helps, I am getting ready to tackle my 2000 this week.

 

I will add... get and install a full o-ring kit to all the connections you open during the work. They never seem to reseal once loosened up and will leak sooner or later.

 

1,250 - hell of a deal...

You won't believe what it costs in 2011.