When your car is in need of an air conditioning repair it is best to do a complete A/C inspection of all related components since the problem can be numerous things. You will first want to inspect your fan belts, related connections and hoses then move on to a visual inspection of the air conditioning compressor. Sometime this can be difficult since in many vehicles the compressor is well hidden. When inspecting the compressor you will want to look for any oil that might be leaking and check the clutch and bearings to make sure they are in good working condition. Next you will check the clutch in the compressor. If you look at the compressor you will notice there is an air gap between the bearing face and the compressor clutch. You will want to inspect the clutch air gap and make sure it falls into the proper specification. In order to measure the air gap you will need a gap gauge. Slide the gauge between the clutch and bearing face and make sure it is not thinner than 0.014 and no more than 0.030.
Inspection of the clutch in the compressor
If your compressor is driven by a belt then you will have a magnetic clutch on the input shaft that cycles the compressor off and on to control the air conditioners cooling function. If the clutch is worn is can be replaced separately. If the compressor is bad the new one may not come with a replacement clutch. It is best to install a new clutch if you are replacing the compressor.
Once the compressor is replaced it is a good idea to change the A/C hoses. When the old compressor failed it will put metallic debris into the system. This can result in blocked orifice tubes which can damage the new compressor. Making sure all the debris is out of the system is important to not having another failure with your new compressor.