Hey guys kinda new on here. Anyways, the a/c doesn't work on my 98 S70 GLT. I thought I remembered reading somewhere about some cheap trick of something you could jam in the clutch to get it to make contact.. anybody know what i'm talking about?

Thanks!

 

There are multiple reasons why the AC compressor clutch might not engage:

1. Low on freon
2. bad low and/or high pressure switch
3. bad compressor
4. compressor clutch needs re-shimming
5. other issues..

Have you checked any of those things?

 

I put a can or refrigerant in it a couple months ago.. but other than that no I haven't checked any of that out yet

 

update: pretty sure it's not low on freon, when I have the a/c on it blows hard but it's not cold. I can here a clicking noise coming from the compressor like its trying to engage but doesnt, it clicks every couple seconds as long as the a/c is on. This is what makes me think the clutch needs shimming.... and because it blew cold a couple months ago and seemed to go out randomly one day

 

When the system gets low on freon, it cycles the compressor. You need to make sure it's not low and proceed from there.

If it is low, it's likely leaking from somewhere. If the evaporator is leaking, it's not worth having it fixed by anyone, hardly by yourself. They usually leak just a little bit, less than a can per month. If that's the case, just can it up once per month.

 

my clutch was doing the exact same thing and it took almost a complete can before it stopped cycling the compressor constantly. it eventually started cycling less and less.

if you have the can with the pressure gauge on it, you will see that when it clicks on the pressure starts to drop and once it gets fairly low it will click back off, this is a safety feature to keep the system from getting damaged due to low/high pressure do NOT jam the clutch as you may damage the system more.

most likely you have a leak but if you haven't filled it with a pressure gauge there is really no way to know if that is the issue or not. (that i know of mwahaha)

 

Thanks guys! now, since it's assumed (by you all and me) that I have a leak somewhere...
Any tricks on how to find it?

 

Well, it's not a trick. The most likely leak is the evaporator. What you should do is, service the system with freon with dye in it. Then purchase the glasses kit with the black lite and check for the glow a few weeks later. Most leaks are slow and may take a month before the system is low enough to service again (a bad leak). Look around the engine compartment along the lines, compressor, dryer and other ac lines to see if any of them have the dye glowing. If you can't see a leak in the motor compartment, the leak is likely in the evaporator. You can remove something under the dash and visually check the evaporator.

IMO, if the evaporator is leaking, it's not worth repairing unless it's a bad leak, more than a can per month. The 134 freon does not harm the ozone so there is no real reason to fool with it.

 

There are two issues. The first involves the clutch air gap on the compressor. There are backyard ways to "rig" this, but the most effective repair is to remove the compressor, remove the end of the clutch plate, remove the shim, and reinstall. You will have a very close air gap and that will take care of the problem if the compressor is otherwise okay.

Since you are recovering the charge to pull the compressor, use new o-rings at the compressor. Also, install a new drier and, while you have the system apart, pull the orifice tube. If it is nasty, consider a new compressor, condenser and flush. Otherwise, clean or install a new one and put it back together.

Vacuum for at least 30 minutes. Inject refrigerant oil and charge system to capacity. That will mostly take care of your compressor issues.

For a leaking evaporator, I must disagree with adding refrigerant over and over again. At over $10 can, you will, depending on your climate, be spending $60 a year on refrigerant and the leak will only get worse. Pull the dash and replace that thing. It is not that bad of a job.

 

Thanks for all the help guys, unfortunately a/c systems are way not my forte, and I considered the replacement of the heater core not too long ago a huge PITA hahaha.

The car is a daily driver, so for now I think i'm just gunna put refrigerant in it and see if it works, then when I get time to tear into it further I will