This product has been superseded by: 6DA-12411-01-00. Yamaha Thermostat 6DA-12411-00-00. Overview. The Yamaha Thermostat 6DA-12411-00-00 is a genuine original equipment manufacturer component designed to regulate engine temperature and maintain proper cooling system performance. The thermostat automatically controls the flow of cooling water through the engine, helping ensure the engine reaches and maintains its optimal operating temperature.. A properly functioning thermostat is essential for e