How/where do I add oil to new A/C compressor?

[dan2286]

I got it going today. I just poured about 6 oz into the compressor in both sides like you guys said. There was no oil in the system for some reason. It's blowing cold air now. The pressure is high (55/250) but it's working. Not sure why the pressure is high. My shop manual says it should have 3.75lbs of freon. I added 3 lbs and stopped since the pressures were high. I'll see what it does for awhile unless someone has a suggestion.

I am not positive because I haven't dealt with a/c in a while, but I think the pressure specs are supposed to be at a specific outside air temp. I believe there are charts out there to look at.

 

[Ribbedroof]

Pressure will be higher than R12 pressures when using R134a

 

[gs dewd]

also when converting from r-12 to 134a your charge will be 80% of the r-12 charge. Which would be around 3lbs. Also what was the temp at the front of the car when taking the pressure readings? If it was high the the pressures will go up.

 

[tc1959]

You need to flush the system with ac flush or something similar like rubbing alcohol then blow all liquid out with a clean supply of compressed air. Then on most GM systems you add 6 to 8 OZ of oil 525 mineral oil, for r12 or pag synthetic oil for 134a. I would not recommend ester as it does not provide proper lubrication when mixed with the old oil in the system. also stay away from freeze 12 or any other so called replacement refrigerants. Add your new oil to the NEW accumulator. do not pour it in to the compressor as liquids will not compress and it could cause damage to the guts of your new part.
I have been doing this for over twenty-five years now at the dealership , It hasn't failed me yet.

 

[carmangary]

Thanks. I just poured it into the compressor ports and turned it 12 or so times once it was all hooked up before starting. It's been working fine ever since. I don't think my charge is perfect but it blows nice cold air so it's good for me. I flushed the evaporator and lines with AC flush. I didn't flush the condensor because I didn't want to remove it from the car. I should have just poured some flush in it and blew some air through it but didn't think of it at the time. Hopefully, I won't have any problems. The compressor was cheap though, so if it fails I won't be too upset.