Any F50’s replaced a/c compressor?

[O5Q45]

As heading asks, have any of you F50 owners replaced your compressor? If so, around how much? What parts must be replaced when I get the compressor replaced? It still works but has been making a “knocking” type sound faintly at idle. So I don’t think there would be any debris in the system, but what do I know.. any of your F50’s a/c compressor made this noise I described? If so; what was the outcome or are you still motoring- I don’t want it to lock up on my way to work since I drive to Asheville via I-26 at 3:45 am up a 3400ft elevation mountain daily and at 5-10 below before..

[EdBwoy]

The knocking might be pulley bearing related. Does it change at all when you engage/ disengage the clutch by turning the AC on/ off?

What parts must be replaced when I get the compressor replaced

Here are 2 threads I've come across recently with posters who have immense knowledge on AC systems in general:
1. replacing-ac-compressor-on-2007-m45-t616954.html
2. ac-not-working-dye-in-the-system-from-t ... 15740.html

A bearing replacement might not be all that bad, but when it comes to fluid replacement, I like to leave that to the pros.

[Q451990]

Having not heard it in person, I can't say for sure - but I think what you're describing is a normal characteristic of the compressor. I know that it is on the older Q45s. On the older Q, the noise comes from the fact that the compressor is variable displacement, and the swash plate inside creates a light rattle or clatter, especially at idle. My wife's '05 G had some compressor noise later in it's life, but it would be more of a moan during acceleration that would go away if I turned the air off. I just kept an ear out for it, and it never seemed to get worse or result in a failure over the course of several years and about 50K miles. I'd just keep an eye on it and see if it gets worse.

[O5Q45]

Yes, that’s what I am hearing as far as your description, the knock clatter noise stops when I shut a/c off and returns with reengagement .. the moan as I accelerate also occurs.. enough for my passengers to ask what the noise is.. you mentioned a variable type compressor; I am going to have to look that one up as I didn’t come across that in my online googling.. the one thing I have noticed that is very strange to me is I can not find the RPM that the compressor kicks off. On ALL other cars I’ve owned, during full throttle Kickdown the A/C kicks off. Although this is the first engine I’ve had that A/C didn’t affect the ability of the motor one bit.. on or off- so.. I’ve idled upto 5,000 RPM and engaged the A/C button and it kicks on.. As far as I know previous cars, high RPMs are not a friend to compressors.. but I find no safety protection on the Q for the compressor as far as RPMs.. my point being, after a high RPM with a\c on I noticed a more pronounced knock and wonder if I have damaged it.. it’s cold as ice, but I don’t want it to lock with a single belt running the show..

[Q451990]

I don't think locking it is a concern, I've never heard of that on any Q45 or Nissan product in general. Your car actually has two accessory belts, so your power steering would not be impacted in a failure. Your real concern would be the water pump. I still think in a worst case scenario you'd notice the failure and be able to stop the car safely without a massive overheat or issue.

[O5Q45]

That makes me feel better for sure. I have to say this car has taught me a lot. When it’s happening it’s awful of course.. but I’ve actually enjoyed the ride. I guess I will continue on with it as is. I’m going to wait for the next sound or symptom.. the thing with the way the climate control is, that anytime I even turn it on it engages the compressor. I have to turn on and cycle with button 6 to off for vent.. I have to have defog capabilities durning the winter and have been pulling the compressor fuse until I needed it. I’m glad to hear of no known lock ups. I assume I would hear something even if driving if it got severe-

[O5Q45]

You mentioned on the older Q that the compressor was variable displacement- how do I figure out if mine is in the F50 model?

[O5Q45]

After reading how each type operates, I assume any car with auto climate control will have variable as this type of compressor can lessen its work load as desired cabin temp is achieved.. hence variable? Correct?

[O5Q45]

Ok lastly, the clatter I hear isn’t always present with system on; so you describe this as per normal with variable type.. does or did the knock clatter noise you hear change or get noticeable based on load and position of s plate for variable cooling or maintaining conditions in cabin?

[Q451990]

I think you're correct on the variable displacement being paired with automatic climate control, but I can envision one that isn't and the system just varies the heater mix door. From reading the FSM, it's a Calsonic V-6 variable displacement compressor.

I've never established a pattern for the noize, but I do know it's more noticeable some times than other. So "it depends" - but I'm not sure what it depends on. My first Q made it to 16 years and 200K on the original compressor (unless it was changed very early in it's life... don't remember now).

I can't find any mention of an RPM cutout for your compressor. I bet it does at some point though...

I compared the specs of the '05 Q45, and '05 G35 compressors - and they're identical. "Calsonic Kansei Make CWE-618" - so I'd say that my experience with the noises on our G35 are pretty comparable to what you're describing. The systems even have identical refrigerant capacities.