{"product_id":"thermostat-fits-yamaha-2-stroke-outboards-3-250-hp-replaces-yamaha-6e5-12411-02-00-sierra-18-3540","title":"Thermostat – Fits Yamaha 2-Stroke Outboards 3-250 HP (Replaces Yamaha 6E5-12411-02-00, Sierra 18-3540)","description":"\u003csection\u003e\n  \u003c!-- 🔧 Table Styles (include only once per page) --\u003e\n  \u003cstyle\u003e\n    \/* Outer container allows horizontal scrolling (with iOS momentum) *\/\n    .ss-table-wrap { overflow-x:auto; -webkit-overflow-scrolling:touch; }\n\n    \/* Base table styles *\/\n    table.ss-table { width:100%; border-collapse:collapse; min-width:640px; }\n    table.ss-table th, table.ss-table td {\n      padding:10px 12px; border:1px solid #e5e7eb; text-align:left; vertical-align:top;\n    }\n\n    \/* Key: prevent wrapping, word breaks, and vertical text in headers *\/\n    table.ss-table th {\n      white-space:nowrap;       \/* Do not wrap *\/\n      word-break:normal;        \/* Don’t break words *\/\n      letter-spacing:normal;    \/* Prevent theme styles from stretching letters *\/\n      font-weight:600;\n      background:#f8fafc;\n    }\n\n    \/* Small screen optimization *\/\n    @media (max-width:480px){\n      table.ss-table th, table.ss-table td { padding:8px 10px; font-size:14px; }\n    }\n  \u003c\/style\u003e\n\n  \u003ch2\u003eProduct Details\u003c\/h2\u003e\n  \u003cp\u003eThis replacement \u003cstrong\u003eThermostat – Fits Yamaha 2-Stroke Outboards 3-250 HP\u003c\/strong\u003e is engineered to regulate engine temperature for optimal performance on a wide range of Yamaha outboards from 1984–2009. It ensures your engine operates within its designed temperature range, preventing overheating and improving fuel efficiency.\u003c\/p\u003e\n  \u003cp\u003eIt serves as a direct replacement for numerous Yamaha, Sierra, and Parsun part numbers, including the common 6E5-12411-02-00 and Sierra 18-3540, ensuring broad interchangeability.\u003c\/p\u003e\n  \u003cul\u003e\n    \u003cli\u003eDesigned for direct-mount installation to the engine block.\u003c\/li\u003e\n    \u003cli\u003eOpens at a consistent 50°C (122°F) for reliable cooling system operation.\u003c\/li\u003e\n    \u003cli\u003ePackage includes the thermostat and a corresponding seal for a complete installation.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n  \u003cp\u003eUse this matrix to confirm equivalent references across OEM and aftermarket.\u003c\/p\u003e\n  \u003cdiv class=\"ss-table-wrap\"\u003e\n    \u003ctable class=\"ss-table\" aria-label=\"Part Number Matrix\"\u003e\n      \u003cthead\u003e\n        \u003ctr\u003e\n          \u003cth\u003eBrand\u003c\/th\u003e\n          \u003cth\u003ePart Number\u003c\/th\u003e\n        \u003c\/tr\u003e\n      \u003c\/thead\u003e\n      \u003ctbody\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-00-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-10-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-20-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-30-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e688-12411-00-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e688-12411-10-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e688-12411-11-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6H3-12411-11-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6AH-12411-00-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-3540\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-3622\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eParsun\u003c\/td\u003e\n\u003ctd\u003eT15-04000010\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003c\/tbody\u003e\n    \u003c\/table\u003e\n  \u003c\/div\u003e\n\n  \u003ch2\u003eEngine \u0026amp; Model Compatibility\u003c\/h2\u003e\n  \u003cp\u003eConfirm your engine model\/year in the table below.\u003c\/p\u003e\n  \u003cp\u003eFitment covers a wide array of Yamaha 2-stroke carbureted and HPDI models from 3 HP to 250 HP. Applications for Parsun models are also listed.\u003c\/p\u003e\n  \u003cdiv class=\"ss-table-wrap\"\u003e\n    \u003ctable class=\"ss-table\" aria-label=\"Engine \u0026amp; Model Compatibility\"\u003e\n      \u003cthead\u003e\n        \u003ctr\u003e\n          \u003cth\u003eBrand\u003c\/th\u003e\n          \u003cth\u003eModel\u003c\/th\u003e\n          \u003cth\u003eRated HP\u003c\/th\u003e\n          \u003cth\u003eStroke\u003c\/th\u003e\n          \u003cth\u003eYears\u003c\/th\u003e\n          \u003cth\u003eOEM Part No.\u003c\/th\u003e\n          \u003cth\u003eNotes\u003c\/th\u003e\n        \u003c\/tr\u003e\n      \u003c\/thead\u003e\n      \u003ctbody\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e9.9F\u003c\/td\u003e\n\u003ctd\u003e9.9\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1984–2005\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e15F\u003c\/td\u003e\n\u003ctd\u003e15\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1984–2005\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e25N\u003c\/td\u003e\n\u003ctd\u003e25\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1994 and up\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e30D\u003c\/td\u003e\n\u003ctd\u003e30\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1987–2000\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e40V\u003c\/td\u003e\n\u003ctd\u003e40\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1989–1997\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e50D\u003c\/td\u003e\n\u003ctd\u003e50\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1995–2000\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e75C\u003c\/td\u003e\n\u003ctd\u003e75\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1994–2000\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e90A\u003c\/td\u003e\n\u003ctd\u003e90\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1984–2009\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e100A\u003c\/td\u003e\n\u003ctd\u003e100\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1990–1999\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e115C\u003c\/td\u003e\n\u003ctd\u003e115\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1994–2009\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e130B\u003c\/td\u003e\n\u003ctd\u003e130\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1989–2001\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e140C\u003c\/td\u003e\n\u003ctd\u003e140\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1987–1993\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e150F\u003c\/td\u003e\n\u003ctd\u003e150\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1984–2009\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e175D\u003c\/td\u003e\n\u003ctd\u003e175\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1994–2000\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e200F, 200G\u003c\/td\u003e\n\u003ctd\u003e200\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1984–2009\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e225D, 225G\u003c\/td\u003e\n\u003ctd\u003e225\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1990–2009\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e250A, 250B\u003c\/td\u003e\n\u003ctd\u003e250\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1990–2009\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eC30\u003c\/td\u003e\n\u003ctd\u003e30\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1993 and newer\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eZ150P, Z150Q\u003c\/td\u003e\n\u003ctd\u003e150\u003c\/td\u003e\n\u003ctd\u003e2-Stroke HPDI\u003c\/td\u003e\n\u003ctd\u003e2000–2009\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eZ175G\u003c\/td\u003e\n\u003ctd\u003e175\u003c\/td\u003e\n\u003ctd\u003e2-Stroke HPDI\u003c\/td\u003e\n\u003ctd\u003e2000–2009\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eZ200N, Z200P\u003c\/td\u003e\n\u003ctd\u003e200\u003c\/td\u003e\n\u003ctd\u003e2-Stroke HPDI\u003c\/td\u003e\n\u003ctd\u003e2000–2009\u003c\/td\u003e\n\u003ctd\u003e6E5-12411-02-00\u003c\/td\u003e\n\u003ctd\u003eSupersedes 6E5-12411-00-00, 6E5-12411-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eParsun\u003c\/td\u003e\n\u003ctd\u003eVarious models\u003c\/td\u003e\n\u003ctd\u003e3-15\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003ctd\u003eT15-04000010\u003c\/td\u003e\n\u003ctd\u003eCompatible with Yamaha 6E5-12411-02-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003c\/tbody\u003e\n    \u003c\/table\u003e\n  \u003c\/div\u003e\n\n  \u003ch2\u003eTechnical Specs\u003c\/h2\u003e\n  \u003cdl\u003e\n    \u003cdt\u003eProduct Type\u003c\/dt\u003e\n\u003cdd\u003eThermostat\u003c\/dd\u003e\n    \u003cdt\u003eInstallation\u003c\/dt\u003e\n\u003cdd\u003eDirect replacement\u003c\/dd\u003e\n    \u003cdt\u003eFuel Type\u003c\/dt\u003e\n\u003cdd\u003eGasoline\u003c\/dd\u003e\n    \u003cdt\u003eConnection\u003c\/dt\u003e\n\u003cdd\u003eDirect mount to engine block\u003c\/dd\u003e\n    \u003cdt\u003eHousing Material\u003c\/dt\u003e\n\u003cdd\u003eBrass\/stainless steel\u003c\/dd\u003e\n    \u003cdt\u003eTemperature Rating\u003c\/dt\u003e\n\u003cdd\u003e50°C (122°F) opening temperature\u003c\/dd\u003e\n    \u003cdt\u003eOperating Temperature\u003c\/dt\u003e\n\u003cdd\u003e50°C (122°F) opening\u003c\/dd\u003e\n    \u003cdt\u003eWarranty\u003c\/dt\u003e\n\u003cdd\u003eVaries by manufacturer - typically 1 year\u003c\/dd\u003e\n    \u003cdt\u003eOther Technical Attributes\u003c\/dt\u003e\n\u003cdd\u003eFor closed cooling system\u003c\/dd\u003e\n  \u003c\/dl\u003e\n\n  \u003ch2\u003eWhat’s in the Box\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003e1 x Thermostat (6E5-12411-02-00)\u003c\/li\u003e\n    \u003cli\u003e1 x Thermostat Seal\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n  \u003col\u003e\n    \u003cli\u003eEnsure the engine is completely cool before starting. Disconnect the battery.\u003c\/li\u003e\n    \u003cli\u003eLocate the thermostat housing on the engine block or cylinder head.\u003c\/li\u003e\n    \u003cli\u003ePlace a drain pan under the housing and remove the housing bolts to release any trapped coolant.\u003c\/li\u003e\n    \u003cli\u003eRemove the old thermostat and its gasket or seal. Note its orientation.\u003c\/li\u003e\n    \u003cli\u003eClean the mounting surfaces of the housing and engine block thoroughly.\u003c\/li\u003e\n    \u003cli\u003eInstall the new thermostat and seal in the correct orientation.\u003c\/li\u003e\n    \u003cli\u003eRe-install the housing cover and tighten the bolts to the manufacturer's specified torque.\u003c\/li\u003e\n    \u003cli\u003eReconnect the battery, refill the cooling system, and check for leaks after starting the engine.\u003c\/li\u003e\n  \u003c\/ol\u003e\n\n  \u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow do I know if my thermostat is failing?\u003c\/summary\u003e\n    \u003cp\u003eCommon signs include engine overheating (temperature gauge in the red), or the engine running too cool and not reaching operating temperature. You may also notice fluctuating temperature readings, coolant leaks around the housing, or poor engine performance and fuel economy.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eIs this thermostat the same as the OEM Yamaha part?\u003c\/summary\u003e\n    \u003cp\u003eWhile this is an aftermarket part, it is designed to the same specifications for temperature rating (50°C), fit, and function as the original Yamaha 6E5-12411-02-00 thermostat. The materials (brass\/stainless steel) are comparable for durability and corrosion resistance.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eCan I install this myself?\u003c\/summary\u003e\n    \u003cp\u003eYes, replacing a thermostat is a common maintenance task for those with basic mechanical skills. However, ensuring surfaces are clean and bolts are torqued correctly is critical. If you are not comfortable performing the work, professional installation is recommended.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat is the purpose of the 50°C (122°F) opening temperature?\u003c\/summary\u003e\n    \u003cp\u003eThis specific temperature rating allows the engine to warm up quickly to an efficient operating temperature and then opens to allow coolant to circulate, preventing it from overheating. It's critical for performance in both cold and warm water environments.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eOEM vs. Aftermarket?\u003c\/summary\u003e\n    \u003cp\u003eThis listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eShipping speed \u0026amp; cost\u003c\/summary\u003e\n    \u003cp\u003eWe ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWarranty \u0026amp; returns\u003c\/summary\u003e\n    \u003cp\u003eCovered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused \u0026amp; in original condition). See our policy page or reach out for instructions.\u003c\/p\u003e\n  \u003c\/details\u003e\n\n  \u003ch2\u003eSafety \u0026amp; Important Info\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eVerify images\/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.\u003c\/li\u003e\n    \u003cli\u003eThis is an aftermarket replacement, not an OEM component.\u003c\/li\u003e\n    \u003cli\u003eProfessional installation is recommended for safety and performance.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003ePro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.\u003c\/li\u003e\n    \u003cli\u003eFast Global Fulfillment — Free standard delivery to most regions in 5–15 days.\u003c\/li\u003e\n    \u003cli\u003eManufacturer-Direct Value — Fair pricing without compromising on materials or QC.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50723967009083,"sku":"17TH050","price":18.49,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/Outboard_Thermostat_for_Yamaha_2_Stroke_3-250_HP_Outboard_Motors__6E5-12411_-_JLM_MARINE-8286964.jpg?v=1763038658","url":"https:\/\/seasierra.com\/products\/thermostat-fits-yamaha-2-stroke-outboards-3-250-hp-replaces-yamaha-6e5-12411-02-00-sierra-18-3540","provider":"SeaSierra","version":"1.0","type":"link"}