There is no adjustments to your a/c clutch, if it will not engage. There is an electrical issues the clutch magneto not receiving and voltage to activate your a/c clutch.
You can check for voltage on the wire leads at the a/c clutch, if you have no voltage there. Your going top have to trouble shot why you have no voltage and you can check to see if your a/c clutch magneto is working by running a hot wire to it from the battery to have it activate. But don't run the compressor to long just in case your low on R134a, don't want to burn up a good $400.00 compressor.