Automotive Air Conditioning Information Forum (Archives)

snowman on Wed May 30, 2012 8:56 AM

Year: 2000
Make: Opel
Model: Astra
Engine Size: 1.6L
Refrigerant Type: R-134a
Ambient Temp: 30.0 C
Country of Origin: Italy

I have a question regarding a 2000 Opel Astra (I am on a military installation in Europe). I had an A/C problem, that looked like my compressor clutch was not engaging. I was getting a good voltage on the leads to the compressor, but the clutch never engaged. I swapped out the entire compressor with a used compressor (that tested good). This compressor worked great for about 30 minutes and then stopped working. This one also looks like the clutch is not engaging. The voltage is fine. Can anyone think of why I could be burning up clutches on different compressors? Or could I have really just had that kind of bad luck? What are the odds?! I am in the process of rebuilding the clutch on the original compressor and will be trying my luck again with that one. Thanks in advance.

Cussboy on Wed May 30, 2012 9:18 AM

If getting correct voltage, an AC clutch can fail to engage for some reasons that I can think of. This doesn't mean that all these instances are equally common:

1. improper gap, like too large, or too far away for the electromagnet to engage the clutch. A dangerous way to check for this is to start the engine, turn the AC on, leave in park (as your legs won't get as tired), and tap on the center of the AC clutch with a wooden rod or tool handle. Do I need to repeat that doing such on a running engine, with belts and pulleys moving, is potentially dangerous, so proceed with eye protection and great caution !!!

2. compressor clutch actually engaging but not turning the insides of the compressor? Is there any squealing like compressor locked up or reluctant to turn because of high pressures?

3. poor grounding or AC compressor/AC clutch (not likely). Many have just a positive wire connection. Some also have a second ground wire; if so, don't overlook that. Ground that second wire temporarily to check.

Edited: Wed May 30, 2012 at 8:11 PM by Cussboy