88 Cherokee. Had it about several months now. A/C has not been working. Compressor kicks on but doesn't blow cold. I was going to charge it up but can't get the little valve to open so I can recharge. Any ideas?
It has been converted to 134a but still has the 'screw out' recharge valves..

Great description I know right , but not sure what to call them. I'm thinking it's just low on freon and want to check to see if that is the issue. thanks!

 

Are you turning valve clockwise to open? Turn clockwise about one turn or so. Turn too far and valve closes on the other end,