Like the other posters have said check for a bad ground and power to the clutch.
It is the first step to take.

A straight jump from the battery should make it click. You should be able to see the front plate jump towrds the compressor slightly. By the way you can do all of this with the engine off!

A best guess it is the clutch coils internal wires themselves may be going south after it heats up from use. They are very fine inside and so are they coming out to play in our real world.

As mentioned there is one you can see and the other one goes to the bracket that holds on the whole affair onto the compressor. There may even be a ground to your compressor if it is rubber mounted.

You said you have been tapping for a while is a big clue.
It is soon after these methods they will quit all together.

I would leave it on for a bit to warm up. Then disconnect and reconnect it several times to mimic your conditons you described.


The pressure of the system corresponds to air temperature. Look up the vapor pressure of your refrigerant you are using on a conversion chart or a gauge set.

The system should be as ambient air or the same as the side panels on the body of the car, before running the engine. Of course, this will tell you nothing except you have some gas filling the space. The state of charge has to be measured by the weight of liquid to be the most accurate for your designed system.

Those vapor pressure readings, while the system is running, are approximately the temperature of the evaporator and condenser refrigerant. Minus or plus 10 degrees for conduction through the tubes of low or high side.

These are all rules of thumbs from both hands here which depend on some heat load factors, like humidity!
On the evaporators I like to see a good 30 to 40 degrees exchange of temperatures on gages to the real world of air on any system. Then I know things are clean and the design is working the refrigerant for all it is worth.

Now days, that can be some bucks and you do not want to get me started there!

Also, I am originally (40 years ago/from) Clarksville, Tennessee and during the summers of right now, glad of it!

Phil