It does sound like the compressor is locking up if you are leaving the system off the pulley is able to spin. If when you engage it, it starts smoking then it is most likely locked up.
Here is a link to a popular website with pretty reasonable prices:
Unfortunately, we need to possibly redo some of what you have done but here is a guide that includes things to think about when replacing a compressor:
Let us know how you make out. Thanks
Wednesday, July 1st, 2020 AT 2:53 PM