Hydrovane oil was red up until last year, they’ve now changed to clear. Flush the oil and add the red stuff. Maybe change separator filter when doing it aswell. Don’t put the compair oil in that’s for screws
On the unloaded valve there will be a switch on the other side of where you have taking the picture, on start up the compressor takes in a little air and this switch opens for the Compressor to kick in, if the switch doesn’t open the compressor will shut down due to it thinking there’s no air...