Guys, thank you so much. I just opened another engine I had lying around as a spare and the motor inside is identical, just sits inside the plastic casing. So will be swapping that out to the Shuttle train at some point soon (need to get a soldering iron first).
Also found some videos from a thread Chrisjo has mentioned, and found out you can order a Tamiya motor replacement on eBay. This has been very helpful!
Also found some videos from a thread Chrisjo has mentioned, and found out you can order a Tamiya motor replacement on eBay. This has been very helpful!