got a scout II with the original air conditioning system the 40 year old york compressor still works and still blows cold air, but it is very loud. is there a way to oil the compressor ? or is all the oil in the Freon charge. ? i attached a picture from the internet of the york compressor. common sense is kinda telling me the bolt/screw in the middle would access the crank case of the compressor and there must be oil in there. is that correct ? and if that is correct can a man remove that bolt/screw with out discharging the A/C system. again common sense says there would not be a freon charge in the crank case of the compressor. but really i dont know, i have never opened up this compressor. any ideas out there ?