{"product_id":"thermostat-fits-mercury-mariner-f40-f50-f60-efi-4-cylinder-4-stroke-outboards-replaces-8m0117413-8m0168892","title":"Thermostat – Fits Mercury\/Mariner F40\/F50\/F60 EFI 4-Cylinder 4-Stroke Outboards (Replaces 8M0117413, 8M0168892)","description":"\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 *\/\ntable.ss-table { width:100%; border-collapse:collapse; min-width:640px; }\ntable.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 *\/\ntable.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\u003csection\u003e\n  \u003ch2\u003eProduct Details\u003c\/h2\u003e\n  \u003cp\u003eThis is a replacement \u003cstrong\u003eThermostat – Fits Mercury\/Mariner F40\/F50\/F60 EFI 4-Cylinder 4-Stroke Outboards (Replaces 8M0117413, 8M0168892)\u003c\/strong\u003e. It is designed for 40, 50, and 60 HP 4-cylinder EFI models with serial numbers 1C050252 and higher, regulating engine temperature for optimal performance and longevity.\u003c\/p\u003e\n  \u003cp\u003eThis part is a direct interchange for Mercury OEM parts 8M0117413 and 8M0168892, as well as Sierra 18-3640 and OMAX 8M0117413.\u003c\/p\u003e\n  \u003cul\u003e\n    \u003cli\u003eEngineered for direct-fit installation in the original thermostat housing.\u003c\/li\u003e\n    \u003cli\u003eBuilt with corrosion-resistant materials for saltwater and freshwater environments.\u003c\/li\u003e\n    \u003cli\u003eIncludes one thermostat, ready for installation.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\u003csection\u003e\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 Cross-Reference\"\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\u003eMercury \/ Mariner\u003c\/td\u003e\n        \u003ctd\u003e8M0117413\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury \/ Mariner\u003c\/td\u003e\n        \u003ctd\u003e8M0168892\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eSierra\u003c\/td\u003e\n        \u003ctd\u003e18-3640\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eOMAX\u003c\/td\u003e\n        \u003ctd\u003e8M0117413\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n  \u003c\/div\u003e\n\u003c\/section\u003e\n\u003csection\u003e\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\u003e\u003cb\u003eFor Mercury\/Mariner Owners:\u003c\/b\u003e This thermostat fits specific 4-cylinder EFI 4-stroke outboards (40, 50, 60 HP) within the serial number range 1C050252 and up. Please verify your engine's serial number before ordering.\u003c\/p\u003e\n  \u003cdiv class=\"ss-table-wrap\"\u003e\n    \u003ctable class=\"ss-table\" aria-label=\"Compatible Engine Models\"\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\u003eMercury\u003c\/td\u003e\n          \u003ctd\u003eF40 EFI\u003c\/td\u003e\n          \u003ctd\u003e40\u003c\/td\u003e\n          \u003ctd\u003e4-Stroke\u003c\/td\u003e\n          \u003ctd\u003eSerial: 1C050252 \u0026amp; up\u003c\/td\u003e\n          \u003ctd\u003e8M0117413\/8M0168892\u003c\/td\u003e\n          \u003ctd\u003e4-cylinder\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eMercury\u003c\/td\u003e\n          \u003ctd\u003eF50 EFI\u003c\/td\u003e\n          \u003ctd\u003e50\u003c\/td\u003e\n          \u003ctd\u003e4-Stroke\u003c\/td\u003e\n          \u003ctd\u003eSerial: 1C050252 \u0026amp; up\u003c\/td\u003e\n          \u003ctd\u003e8M0117413\/8M0168892\u003c\/td\u003e\n          \u003ctd\u003e4-cylinder\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eMercury\u003c\/td\u003e\n          \u003ctd\u003eF60 EFI\u003c\/td\u003e\n          \u003ctd\u003e60\u003c\/td\u003e\n          \u003ctd\u003e4-Stroke\u003c\/td\u003e\n          \u003ctd\u003eSerial: 1C050252 \u0026amp; up\u003c\/td\u003e\n          \u003ctd\u003e8M0117413\/8M0168892\u003c\/td\u003e\n          \u003ctd\u003e4-cylinder\u003c\/td\u003e\n        \u003c\/tr\u003e\n      \u003c\/tbody\u003e\n    \u003c\/table\u003e\n  \u003c\/div\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eTechnical Specs\u003c\/h2\u003e\n  \u003cdl\u003e\n    \u003cdt\u003eProduct Type\u003c\/dt\u003e\n\u003cdd\u003eMarine Engine Thermostat\u003c\/dd\u003e\n    \u003cdt\u003eInstallation\u003c\/dt\u003e\n\u003cdd\u003eDirect replacement in thermostat housing\u003c\/dd\u003e\n    \u003cdt\u003eTemperature Rating\u003c\/dt\u003e\n\u003cdd\u003e122°F \/ 50°C\u003c\/dd\u003e\n    \u003cdt\u003eMaterial\u003c\/dt\u003e\n\u003cdd\u003eDurable corrosion-resistant construction\u003c\/dd\u003e\n    \u003cdt\u003eOperating Environment\u003c\/dt\u003e\n\u003cdd\u003eMarine (salt\/fresh water)\u003c\/dd\u003e\n    \u003cdt\u003eEngine Type\u003c\/dt\u003e\n\u003cdd\u003e4-Stroke EFI outboard\u003c\/dd\u003e\n    \u003cdt\u003eApplication\u003c\/dt\u003e\n\u003cdd\u003eEngine cooling system regulation\u003c\/dd\u003e\n  \u003c\/dl\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eWhat’s in the Box\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003e1 x 122°F\/50°C Outboard Thermostat (Replaces 8M0117413\/8M0168892)\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n  \u003col\u003e\n    \u003cli\u003eDisconnect the battery to prevent accidental starting.\u003c\/li\u003e\n    \u003cli\u003eAllow the engine to cool completely before beginning work.\u003c\/li\u003e\n    \u003cli\u003eLocate the thermostat housing on the engine block. Place a drain pan underneath.\u003c\/li\u003e\n    \u003cli\u003eCarefully remove the bolts securing the housing cover. Note any coolant that drains out.\u003c\/li\u003e\n    \u003cli\u003eRemove the old thermostat and any gasket or sealing material.\u003c\/li\u003e\n    \u003cli\u003eClean both the housing and cover mating surfaces thoroughly.\u003c\/li\u003e\n    \u003cli\u003eInstall the new thermostat in the correct orientation.\u003c\/li\u003e\n    \u003cli\u003eRe-install the housing cover with a new gasket (if required) and tighten bolts to manufacturer specifications.\u003c\/li\u003e\n    \u003cli\u003eRefill the engine cooling system with the recommended coolant.\u003c\/li\u003e\n    \u003cli\u003eReconnect the battery, start the engine, and check for leaks and proper temperature gauge operation.\u003c\/li\u003e\n  \u003c\/ol\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow can I confirm this thermostat fits my engine?\u003c\/summary\u003e\n    \u003cp\u003eThis part fits Mercury\/Mariner 40, 50, and 60 HP 4-cylinder EFI outboards with a serial number of 1C050252 or higher. The most reliable way to confirm fitment is to check your engine's serial number against this range. You can also cross-reference your existing part number with the numbers listed in our Part Number Matrix.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat are the signs of a faulty thermostat?\u003c\/summary\u003e\n    \u003cp\u003eCommon symptoms include engine overheating (stuck closed) or taking too long to warm up to operating temperature (stuck open). You may see a temperature alarm on your gauges, notice steam from the engine, or experience poor performance and efficiency.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat is the operating temperature of this thermostat?\u003c\/summary\u003e\n    \u003cp\u003eThis thermostat is rated to open at 122°F \/ 50°C, helping your engine maintain its ideal operating temperature for performance and fuel efficiency.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eCan I install this myself?\u003c\/summary\u003e\n    \u003cp\u003eWhile installation is straightforward for those with mechanical experience, we recommend professional installation to ensure it's done correctly. Improper installation can lead to coolant leaks and engine overheating.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eDoes this include a new gasket?\u003c\/summary\u003e\n    \u003cp\u003eThis listing includes the thermostat only. The thermostat housing gasket is sold separately and should be replaced during installation to ensure a proper seal.\u003c\/p\u003e\n  \u003c\/details\u003e\n    \u003cdetails\u003e\n    \u003csummary\u003eHow often should an outboard thermostat be replaced?\u003c\/summary\u003e\n    \u003cp\u003eThermostats don't have a fixed replacement interval, but it's good practice to inspect them during regular cooling system service (e.g., every 300 hours or 3 years) and replace them if there are signs of corrosion or if the engine shows symptoms of poor temperature regulation.\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\u003c\/section\u003e\n\u003csection\u003e\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\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003e\n\u003cb\u003ePro-Grade Standards\u003c\/b\u003e — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cb\u003eFast Global Fulfillment\u003c\/b\u003e — Free standard delivery to most regions in 5–15 days.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cb\u003eManufacturer-Direct Value\u003c\/b\u003e — 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":50723974283579,"sku":"23TH630","price":16.98,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/Thermostat_for_Mercury_Mariner_F40_F50_F60_EFI_4-Cyl_4-Str_8M0117413_8M0168892___8M0117413_8M0168892_-_JLM_MARINE-8291231.jpg?v=1763038953","url":"https:\/\/seasierra.com\/products\/thermostat-fits-mercury-mariner-f40-f50-f60-efi-4-cylinder-4-stroke-outboards-replaces-8m0117413-8m0168892","provider":"SeaSierra","version":"1.0","type":"link"}