Chosen Solution
Can you buy replacement motors?
carolyn.menzies39 we would need to know if this is Thomas the Tank Engine or Thomas & Friends Thomas with Track . One uses a higher voltage motor etc. 6V vs. 12V So see what you can find out to identify and clarify. In the meantime take a look at the guide Disassembling the Thomas Ride On Train Step 4 shows the motor. You may have to disassemble it and post some good pictures so we can see what it looks like and provide more help to get you motor for it. Post plenty of pictures with your QUESTION so that we can see what you see.
If you can find a model number on the motors you might find something online. Or if you can find the specs like voltage and amperage you might be able to find something comparable.