Failed AC compressor

[Ndx]

Hi Guys,

So of course before 400 miles trip ... AC failed on my Cayenne....

Checked fuses
Hooked up gauges ...
- all fine

But then I looked at the AC pulley ... and could tell that something is wrong ..looks like it kinda separated .. the middle part is no longer spinning only the pulley ...

Found replacement compressor ... looks like OEM is made by Denso

Do I need to replace anything else .. ? Do I need to add in line filter do flush ?

Or can I evacuate system, replace compressor add oil do vacuum and re fill the system.

I read online ... that I should replace everything in AC system

thx

 

[Merkava_4]

When I replaced the compressor on my Buick, I poured the oil out of it into a measuring cup so that I knew how much oil to add to the new compressor. The other part I replaced was the orifice tube. The last thing I did before I started buttoning the system up was I back flushed the condenser with denatured alcohol. After getting the system all buttoned up, you would normally take the system into a deep vacuum to boil off all the moisture, but on the day that I was doing mine, the temperature outside was 110F with zero percent humidity. Here's a picture of the back flush kit:

 

[Ndx]

great, sounds good

I will pickup the flush kit ...

And order the dryer/orfice tube

The new compressor actually comes pre filled with oil

thank you

 

[JHZR2]

It all depends upon if the compressor threw debris into the system. In my one experience, a compressor seizure caused the belt and pulley to fail. I wonder if a coupling snapped or if an actuator just burned out?

Unfortunately it's probably something you have to open up and look at...

 

[Andrew1972]

If ac clutch is off compressor does not spin. Have you checked ac clutch is getting power and also tried jumping it to rule out electrical issues(ac relay)?

 

[Jetronic]

does the compressor have a clutch, or does it just have an adjustable swash plate and did the compresor seize and pop the rivets? the one in the picture doesn't have a clutch

 

[NHGUY]

Even if the new compressor is filled with oil,you still need to measure how much is in the old compressor and only put that amount back into the new one (after emptying it).Too much oil will reduce the cooling effect and can actually lock up the compressor.

 

[Trav]

It sounds more like an electrical issue than a mechanical one. Did you check for power at the compressor with the switch one?
It could be a bad relay or pressure switch, i just had 2 cars in the last week with failed ones. Check it out thoroughly before throwing the compressor out or you will still have the problem.

Knowing the year and engine would help.

 

[Chris142]

If it did lock up it will need the condenser along with the other parts mentioned. Drain the new compressor as you dont know how much oil it has. After flushing add the recomended amount of oil.

 

[Ndx]

Hi Guys,

its 2011 Porsche Cayenne S. 4.8 v8
The compressor looks exactly like the one the picture.

The riveted part has split on the top and is no longer spinning ... only pulley is moving.

I did check for power all is good ..
So it is failed compressor.

Question is if I should go to extremes and replace whole system condenser,lines etc ?

or flush + inline filter

Denso says that compressor is filled with proper amount of oil ... .

thank you

 

[Nukeman7]

[

The riveted part has split on the top and is no longer spinning ... only pulley is moving.

I did check for power all is good ..
So it is failed compressor.

NO,NO, NO...your compressor is fine, it is the magnetic A/C clutch that has failed. You don't need to replace the compressor or open up the sealed pressurized system. Just replace the external clutch (or have a shop do it). It will be ~$300, not ~$1500.

 

[Ndx]

thinking about it .. I was hearing some noise ... from time to time .. is possible that the clutch was making noise.

Thank you

 

[KrisZ]

Originally Posted By: Nukeman7
[

The riveted part has split on the top and is no longer spinning ... only pulley is moving.

I did check for power all is good ..
So it is failed compressor.

NO,NO, NO...your compressor is fine, it is the magnetic A/C clutch that has failed. You don't need to replace the compressor or open up the sealed pressurized system. Just replace the external clutch (or have a shop do it). It will be ~$300, not ~$1500.



I agree with this. The clutch can be gone. Oftentimes it can be replaced without removing the compressor or opening up the system, but I do not know how it would be replaced in this particular car.

 

[Jetronic]

Originally Posted By: Ndx
Hi Guys,

its 2011 Porsche Cayenne S. 4.8 v8
The compressor looks exactly like the one the picture.

The riveted part has split on the top and is no longer spinning ... only pulley is moving.

I did check for power all is good ..
So it is failed compressor.

Question is if I should go to extremes and replace whole system condenser,lines etc ?

or flush + inline filter

Denso says that compressor is filled with proper amount of oil ... .

thank you



I've seen a lot of compressors of that type. They can't be switched off, the least they can do is about 10% of the rated volume. I've seen a lot of them, because they always fail if the system is allowed to run out of refrigerant and the lubrication suffers.

if the rivets popped out, the compressor has seized. This is a fail safe to allow you use of the serpentine belt.

Fit a new compressor, get the system vacuumed and properly filled and you're good to go. Budget for a regas every few years, to stay ahead of lubrication issues due to low charge. Only fit a new condensor or filter/dryer if there's a leak found after vacuuming.

there is NO CLUTCH on this kind of compressor, and no OFF switch for the AC system either.

 

[Ndx]

Thx guys ... rivets didn't pop out .. but they are not moving ... I can see that inside of it a wheel is spinning ...

Thx

 

[Chris142]

If Thats a clutchless compressor its always pumping.the rivits act as a fuse so when it locks up you can still drive the car.

 

[wtd]

If the compressor has in fact seized, you will have to replace pretty much everything as the debris will probably have gone throughout the system. Also most of the new condensors are not easily flushed and I usually just replace them as they usually don't cost much.

If this system has an orifice tube, find it and pull it out and it will give you an indication if the compressor seized as debris will get caught in the OT.

As others have said, it might just be the clutch and not the compressor.

Wayne