Jeep Cherokee (51) air con intermittent

[MrH]

Hi all,

Air con in the jeep is currently intermittent. Clutch might spin, might not. Had it regassed and fully checked today and no leaks. Previous owner said a tap on the front of the clutch wheel will get it going, which indeed it does, a slight tap gets it spinning!

However switch engine or air con off and it wont start again.

Any suggestions what this may be? Obviously it all works ok, but is sticking. Not sure how to solve! Need to though on this weather :-)

Thanks, Mark