Another AC Question

[Matthew K]

When my 95 XJ sport is idling, it sounds like the AC cycles hard. The air still gets pretty cold, but there is definitely a rumbling. Does this sound like the compressor is going bad, or can this noise happen when the refrigerant is low? Is there a good way to check what it might be? Thanks!

Matt

[AZ Jeff]

It may be a symptom of nothing. I have a '92 that has had a rumble in the compressor since I owned it (3 yrs.) Here in Phoenix, the AC gets used a lot (about 8 months of the year for me), so the compressor gets a workout.

It sounds no different now than it did 3 years ago. It's annoying, but have you priced a replacement compressor? A reman is over $300. At that price, I can let it rumble, especially since it cools quite well still.

I would just watch it for changes in noise level or nature, and then take action at that time.

[RTicUL8]

Try this: remove the belt and see if the pulley on the compressor spins freely - it should. If you have a lot of resistance, you should replace it. Note: the only pulley that you shouldn't be able to spin freely is the crackshaft pulley(bottom/center).

[AZ Jeff]

Originally posted by RTicUL8
Try this: remove the belt and see if the pulley on the compressor spins freely - it should. If you have a lot of resistance, you should replace it. Note: the only pulley that you shouldn't be able to spin freely is the crackshaft pulley(bottom/center).

Your suggested test is a good one for the bearing on the compressor pulley, but does nothing to test the actual compressor rotation. Unfortunately, that can only be tested readily by running the engine.

It IS POSSIBLE to have a perfectly good compressor clutch (and bearing in the pulley) and have a toasted compressor.