A/C clutch assembly questions.
The A/C low pressure switch will not be activated (turned on) unless there is approximately 20 psi of pressure in the system. If the A/C will turn on, and there is no "freon" (refrigerant) in the system, then the switch has to be shorted.
To change the clutch asembly requires the following steps;
1. remove the belt. You may have to get the battery out of the way to make this job easier.
2. remove the nut that holds the clutch face on.
3. pull, or pry, off the clutch face from the compressor shaft. There is a special tool for pooling the clutch face, but you can pry it off by driving wood shims between the clutch face and the pulley.
You can also pry it off with screwdrivers, but this could ruin the friction surfaces on the face and the pulley. If you are going to replace the clutch assembly, then this does not matter.
It may be easier to work on the compressor if you unbolt it so you can move it a little. You do not have to discharge the system to do this.
4. Once the face is off, the pulley is held in place by a snap ring. Remove the snap ring, and the pulley should slide off with a little gentle persuasion. Please note the orientation of the snap ring. The beveled side of the snap ring should face you when it is reinstalled.
5. The electrical connection to the clutch coil should be removed, if you have not done this already. The coil is also held on by a snap ring, and the snap ring is also beveled. The snap ring's beveled side should face you when it is installed.
If all you need is a clutch assembly, it can be purchased separately. A new or rebuilt compressor will come with a clutch assembly.
If the A/C pulley bearing is bad:
In the early years, 1989 to 1992, the pulley bearing is available as a replacement part. In the later year SHOs this may not be the case, and you may have to replace the whole assembly.
6. Install everything in the reverse order. Remember to put the snap rings in the right orientation, that is beveled side out (towards you).
Before you go out and buy a new clutch assembly, determine if your compressor is, is is not, in working order.
If you need a new, or rebuilt, compressor you may want to wait until warm weather returns. A new or rebuilt compressor will cost between $250 and $500. If you replace the compressor it would be best to replace the filter/dryer.
In fact, this may be required in order for the warranty to be honored. The warranty requirements may also necessitate a cleaning of the A/C system. If this is the case, you may as well convert to R-134a, if your SHO is a pre-1994 car. 1994s and later are already R-134a systems.
For now, you can unplug the A/C coil, so that it is not activated when the defrost is on. You have time to save up the $600 to $1000 it will take to fix the system in the spring.
Hope this helps, rangerj
