PS2 Fat model laser works fine but the motor/disc won't spin

My PS2 is very old (around 18 years) and has had problems in the past, so I started to fix it. I have managed to fix the disc problems, the laser issues and managed to clean and replace some faulty wires but now the motor won't spin. Every question or video I've seen has different parts and pieces despite it also being a PS2 Fat model. I'm sure its not the laser. Whats been happening is I'll turn on the PS2, place a disc in and then it does nothing. The laser comes on and moves but the motor doesnt spin. It also registers that a disc is in, showing “Reading Disc…” then the message disappearing. I'm assuming I need a new motor but I'd like a second opinion before I do anything else.