Refurbishing a printer can be a tough job. Getting into the nitty gritty details of how to perform each step of refurbishment is a little outside the scope of the type of help we can provide for free through our forum, but I'd like to try to point you in the right direction if I can.
The basic steps to refurbishing a printer are these:
1. Disassemble, clean, and reassemble any components or parts as necessary. Replace if needed.
2. Restore all mechanical functionality, and make sure parts interact with each other as intended.
3. Ensure all electrical connections are good.
4. Flash new firmware, if needed.
5. Test, adjust, and test again.
Eventually, if everything is configured correctly, the printer will work again. If something is off, or not working properly, you'll need to fix it before continuing.
That said, it sounds to me like you're hung up on number 2, as the X axis is not functioning properly. What about it doesn't work?