Any ideas before i start tracing the circuits. I have a feeling the AC clutch might be shorted, but then again that is controlled by the AC relay, so i am not really sure.

The compressor does not come on. Guess it could be a bad AC relay too.

 

There's a 95% chance it's a shorted clutch. Over the past 6 years I've had 4 of them go that same way on a 944T. My last one was a month ago. I think it's fuse # 17 but I could be way off on the fuse #.

 

great, so who sells clutches in case mine is shorted ??

 

Mine went out last week, got a savlage clutch for now and fixed the problem. DO NOT PUT LARGER FUSE IN, it will smoke you climate control. I think the resistance should be around 3-4 OHM, not 0 on the clutch. If you find out where to get the clutch, please post.

 

check the heavy ground wire that is connected to the clutch first - sometimes the plastic burns off and the touch/spark shorts the system

 

Mine went out too, Paragon has them for $200. If you replace just the clutch I dont think you will need to recharge the AC.

Does any one have the writeup on replacing the clutch and what tools are needed?

 

Zims sells clutches as well. I went to autozone and "free" rented their clutch AC pull tools, not a fun job, but that snap ring puller and a socket for the center.

You will not loose any freon charge when you change it.

Honestly you can get a whole unit cheaper on ebay then just the clutch..of course that does require a recharge...but a much easier job!!

 

I replaced the clutch with the compressor in the car, I removed the mounting bolts and tensioner from the compressor and tilted the clutch down and had easy access to the nut, and snap rings. I did not use a puller and had the job done in 45 minutes. The clutch may still be good, just the electro magnet

 

I have done a 928 clutch before, so its not that big of a deal.

Thanks

 

I just want to add a bit to this thread. In general, it is a bad idea to just change a clutch. 95% of the time it is a fault in the compressor that causes the clutch to fail. Very rarely does a clutch just go bad on its own. Sometimes all it takes is a small bind in the compressor. I would spend the extra $100 or so otherwise you could be replacing it again very shortly.

The design of our A/C system is not the greatest as when the car is turned off and the system equalizes, the compressor oil is carried by the freon and collects in the compressor (because it is one of the lowest points of the AC system). The problem with this is most people wait until they're driving down the street @2500 rpm's to turn the a/c on and the extra oil in the compressor puts a tremendous amount of load on the compressor and clutch. Long term use of the system will grenade the compressor, burn up the clutch, or both.

 

Thanks Jeremy,

I have the bad habbit that you just mentioned -- turn on/off the A/C while I am driving the car on road/freeway...

How would you recommend to turn-on/off the A/C? Would it be better if I turn it on/off when the car is stop? Please recommend.

With best regards,
- Alex (87 Diamond Blue 951)

 

I was told by an "old school" auto A/C engineer for GM that you should start and stop the car with the AC on if you plan on using it because the ignition switch is beter suited to handel that load. I'm not sure if I completely believe that theory as modern auto electroncis tend to be a bit more reliable then they were in the 60's but it did make sence. At a minimum, turn the A/C on while the car is idiling.

 

Im an air conditioning mechanic for a living, I do not specilaise in car A/C systems but over 20 years
have had enough experience with my own cars to know where to start.
1. various laws control the gas in the system check your local rules.
2. some cheap butane based replacement gases are an explosion issue.
3. refrigerant gases can be very dangrous if not handled correctly
4. it is not uncommon for the coil side of the clutch to fail with age, the insulation on the windings breaks down with heat and age.
5. to replace the coil with a used item is a wast of time and money.
6. to replace a coil with out replacing the seal and filter is a bigger waste of time
7 .you can source the parts via an auto electrician/ A/C service guy
8.you can remove the above parts with a reasonable puller set and circlip plirers if you know how to
use tools.
9.you still have to regas the evacuate and regas the system. Specialised tools are required along with the
skills to perform the task .
10. you do need to change the oil in the Sanden 10P15E compressors to run on R134A but if done
corectley it works fine.
stay cool
Russell