A/C Clutch Cycles constantly - Help

I have been searching on this topic and it seems likely that my A/C system is low and the low pressure switch keeps the system cycling about every 10-15 seconds.

My question is though...should this be happening even when the AC is not turned on? Because it does.

I just imported this XJ to Canada from WI and is has been doing this. I can't really tell if the A/C works or not because, well, it's damn cold up here right now.

I really don't care if the system works or not right now, I just want it to stop making the constant squeaking and clutching noises...is there a way to cut power to the compressor...so I can deal with it in the Spring, or never?

Thanks :eyes:

There will be a single wire coming out of the front of the compressor, near the pully/clutch.

Follow it about a foot or so and there will be a black plug. Simply disconnect the plug and that will stop the clutch from engaging.

Not sure why it is stuck though, maybe your HVAC controller is screwed. AC will come on with defrost too, FYI. So basically the AC can engage on 4 settings.....max, norm, bilevel, and defroster. Off, vent, and heat are the only settings where the clutch won't engage.

This is assuming you have an 84-96. 97+ have a different set of controls that I am not familar with.

I disconnect the low pressure safety switch in wiinter to keep the AC from running on defrost. Here it is on a 99: [/URL][/IMG]

Great, thanks guys. I will disconnect it right now and I'm sure it will help.

I think the compressor pully bearings are going though because there is some definate noise from that area and it changes when the clutch kicks in. I wish a shorter belt that omits the A/C was available but I guess it isn't due to the fan.

Oh well. Getting the clutch to stop is step one.

Thanks again


PS my XJ is 2001 BTW

Keeping in this line of thought...i know my ac compressor clutch /bearings are shot// basically if i engage the AC..the jeep over heats....anyone ever pulled the clutch and bearings off the front of the AC comprressor unit and replaced the bearing or the clutch? i have got a not so trust worthy person who claims he did it. But, i'd rather hear it from the experts.

thanks.

RLTW,
Grifter

Grifter144 said:

Keeping in this line of thought...i know my ac compressor clutch /bearings are shot// basically if i engage the AC..the jeep over heats....anyone ever pulled the clutch and bearings off the front of the AC comprressor unit and replaced the bearing or the clutch? i have got a not so trust worthy person who claims he did it. But, i'd rather hear it from the experts.

thanks.

RLTW,
Grifter

Click to expand...

It can be done, according to FSM, but the parts aren't cheap. If all that happens is that you overheat, but there's no other noise, I'd be surprised if your diagnosis is correct. I'd check belt tension first, and also make sure that both electric fan and fan clutch are operational. If the clutch is bad, usually what will happen is that the compressor just won't engage well. It might overheat locally, and make a burning smell, but it shouldn't overheat the engine. It certainly did not when it happened on mine. If the bearing in the clutch assembly is bad, you should hear it when the compressor is off, not on. If the bearing in the compressor itself is bad, then that's a whole 'nother story, and clutch repair won't help.

You can replace the AC clutch itself, but you need to take some things into consideration.

First off, the only place I could find an AC Clutch was through the dearlership, at the tune of about $220. Install was another $200 or so.

If you have high miles on your ac, it may not be worth replacing your AC clutch itself, as the compressor may be on it's last legs as well.

Orginally, my AC clutch failed at about 45k miles. I felt the compressor still had some useful life in it, so I had the clutch itself replaced. The AC compressor was still functional, when the AC clutch gave out again at about 110k miles.

At that point, I had the whole unit replaced, even though the compressor was still working. The AC shop that did the work also agreed. They told me that setting the gap on the ac clutch is tricky, and that replacing the compressor with the mileage I had on it was a good idea.....