Auto Air Conditioning & Heater Repair: A/C Freon Capacity, chevy silverado, r134

Question
I have a 1999 Chevy Silverado 5.3L that I am replacing the compressor on. I plan on evacuating and vacuuming the system down. I have a can of R134 with 13oz of freon and 2oz of oil. I bought that priomarily to add the oil. I plan on topping off the system but need to know the capacity to make sure I don't overfill and take out gaskets or hoses and to make sure I have it full.
Do you know the capacity of my totally evacuated system or is it listed somewhere under the hood?
Thanks!

Answer
Replacement compressors usually come with a FULL CHARGE of about 6 to 7 ounces of refrigerant oil.

You need to drain out the old oil from your old compressor and measure the amount that you drained out.

Next you need to empty out all the refrigerant oil from the NEW compressor and reinstall the EXACT same amount of refrigerant oil that you got out of the old compressor and install it into the new compressor. Do NOT use the old oil from the old compressor, Use the NEW oil from the new compressor.

There is a sticker located somewhere on the underside of the hood or on the firewall that tells you the MAXIMUM amount of oil that your complete system contains.

So if you drain out 2 ounces of old oil from the old compressor, Then you would install 2 ounces of fresh oil into the new compressor.


As to adding freon, Locate the BLUE sticker that might even be pasted on the blower motor.