I recently revitalized a YAMAHA MT4X 4 track recorder that had stopped working. The unit in question had a dead motor (exploded capacitor inside the motor, worn brushes). As these motors typically run the entire time the machine is powered up they burn through a lot of hours of use. Everything else in the machine seemed fine however, including the belt.
A new motor was sourced on the internet - a Sankyo SHU2L from a small company in Australia called PROBE - and installed. A transistor controlling motor voltage switching was replaced as well. The machine works fine again and should for many more years.
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