Hi again
The car is Chevrolet Aveo 2010.I have not cheked almost anything yet,but tomorrow or in Sunday i'll have some free time and i'll take a detailed look for trails of oil leaked oil.If there is significant oil leak ,it should have a debris on it,so it must be visible.I doubt it has a serious leak,because he found that the AC is not working,before few days,but he have not used it since the last warm days last summer,so almost half an year has passed.In addition,when the AC is not running,the oil should be settled down in the compressor and the drier,so when the refrigerant has leaked out,there should be almost no oil in the lines and etc. and thus little or no oil should leak out,or at least i think so
After last night i'm sure that the reason for not engaging the clutch is the lack of refrigerant,because i went to the garage to get something,and when i saw the car i decided to open the valve caps and push the schrader valve to see how much force is required to push it back,and no surprise-almost without any resistance,so there is very very low pressure in the system -> no refrigerant .Tomorrow or in the next day i'll check to see if there is something visible.If i don't find anything,i will evacuate,add the UV dye and recheck after few days,but i also want to add a little oil "just in case".I think about 10ml should not be a problem.That's 1/20th of the all mount.After i find and repair the leak,i'll drain and measure the exact amount of oil in the system and will add the proper amount.Any problems in my plans?