AC Compressor failure ?

[Fluke996]

Squealing noise from engine bay the other day so I checked location and sound came from area of A/C compressor. I switched off AC inside the car and squeal went away and I was able to drive the car. Today I pulled the air cleaner housing to visually check, and I saw black goo (grease ?, very dense) coming from the pulley/clutch wheel (See photo). 

My questions are:  Is the compressor likely seized and I need to replace entire compressor or is it just the pulley/clutch and that is repaired separately? Are they mated together and only the entire unit can be replaced? Car is a 99 with 98K miles on odometer. AC had been running Ok with no known issue until this. 

Thanks for any input. 

 

[JFP in PA]

The AC system clutch can be replaced separately, project was covered previously:  https://www.renntech.org/topic/32732-replacing-ac-compressor-clutch/

[Fluke996]

Thanks for the link. Good read, and I see now that the clutch can be bought separately from the compressor. 

What would be the final test to check for which component has failed?

[JFP in PA]

If the compressor had seized, you would have no cooling, and when the clutch engaged, the pulley would simply stop turning and the belt would start slipping.

[Fluke996]

Moving on to the fact that compressor needs replacing, what other AC  parts need replacing at the same time? I saw another article stating once the system is opened to the atmosphere, the drier needs to be replaced because the desiccant will no longer remove moisture. Expansion valve due to particulate entrapment. Those extra components don't add too much to the bill but if we go on to the evaporator core we are getting into big bucks. 

How much is "necessary" to do a reasonable repair?

[JFP in PA]

Depends upon why the compressor failed, and what it damaged in the process. At a minimum, the drier, and if metal is present, the expansion valve (after the system is properly flushed to remove the metal).  You will also need the correct PAG oil for the new compressor. 

[Fluke996]

Thanks for all that information. I'll make sure to bring up those points with the shop.