Here is how I injected pag 46 oil into the pressurized system of my wife's car AC. Not much is needed but a very special tool is required for this job.
Step 1: THE ROBINAIR 16256 OIL INJECTOR.
Simple enough device that allows injection of oil into a fully pressurized system. The instructions are printed on its label. It allows for a maximum of 1/2 Oz of oil per injection.
Step 2: Filling the Oil.
I used a new length of clear tubing to suck oil without getting it in my mouth. Ewwww.
Once the syringe was filled I "jiggled" the plunger to remove air bubbles. This is the exact instruction by Robinair which left my eyebrows crooked for such a laughable term by a reputable company. Anyhow, it worked to get the bubbles out.
Step 3: Injection Time.
I first made sure to turn the blue valve knob fully anticlockwise until it stopped. Next I slipped the coupler onto the low pressure port turned the knob fully clockwise until it stopped.
Starting the car and putting the air conditioning on maximum.
I proceeded to inject the wonderful oil into the system and it required no real effort! Amazing.
Just half Oz is what I needed to sort out my issue. Too much oil will be dangerous to the compressor.
Step 4: Closing Up.
Once I took off the coupler a small remainder of the oil is seen pooled into the port. I closed the port by screwing on its cap and job done! For less than 90USD the Compressor is much quieter and I'm happy.