Finding reliable replacement parts for a Suzuki outboard can be tricky, but this 50°C thermostat is a direct swap for the 17670-90J20 and 17670-90J21. It’s an essential component for anyone running DF 100 through 300 HP engines who wants to ensure their cooling system is functioning optimally and preventing overheating. I love how straightforward the installation is, making it a great budget-friendly find for routine DIY boat maintenance.