Originally Posted by 65ELCMO
I'm a retired compressor mechanic. We had a compressor manufacturer do a oil test and 30 w non detergent come out just the same as compressor oil. Don't worry about it being clear or looking like motor oil. Get the cheep stuff from checker etc. works just fine. If it runs all day you should change it every 3 months. Home owner, once a year is good.
x2... I'm not a compressor mechanic, I agree with you though.