Automotive Air Conditioning Information Forum (Archives)

Airstream on Thu July 21, 2011 6:12 AM

Year: 1984
Make: Suburban
Model: dual-air
Refrigerant Type: R134a

I made a mess while connecting my gauges up to the cold engine the other day:



Yes - that is refrigerant oil, and not antifreeze.

When my truck was converted to R134a several years ago, I never thought to ask which oil (ester or PAG) was used to replace the R12's mineral oil. Now I wonder if all the old oil was removed because the puddle in the next image looks like it is separating:



Is there a color associated with either PAG or ester oil?

Thanks,
Tom

mk378 on Thu July 21, 2011 6:20 AM

The green color is UV dye, which can be added to any oil to make leaks easier to see. Without dye, PAG and ester oils are both clear.