Queation to member who already finished A/C R134A retrofit

[schaats]

Hi,
I have a question about A/C retrofit.
When removing old R12 and oil, how could you did complete suction ?
I asked to A/C shop in my town and heard that it's impossible to remove oil in compressor completely.
R12 can be removed completely, but although using with vacuum pump, remaining oil can not be done completely, they said.
Please inform me your experience.
I'll change 9 old o-rings and receiver drier but not compressor that it's headache to me.
Thank you,

Oh, Min Seok

 

[cruiser_guy]

Generally the oil in the compressor is not a problem. When I did mine I needed a new compressor anyways so it was not a problem. Just go with the advice of the shap and make sure that the new oil and the old oil are compatible.

 

[FL cruiser]

Run a jumper wire from your battery positive to your compressor to engage the clutch. Then take your low side line off the evaporator connection at the firewall. Put a funnel on it and pour paint thinner in it. run your engine. The compressor will suck it up and run it through your system. Run a gallon through. It will make a mess when it's pumped out the evaporator outlet. But it will get alll the oils out of your system. You'll have to blow out the paint thinner from the lines and vacuum it down, but your system will be clean and free of old oils. Best to replace the drier too, because sometimes some thinner and other stuff stays in there and is hard to get out. Best to replace the drier last step before vacuuming down the system.