{"product_id":"thermostat-kit-143-f-62-c-fits-mercury-marine-135-200-hp-v6-outboards-replaces-75692q2-75692t","title":"Thermostat Kit (143°F\/62°C) – Fits Mercury Marine 135-200 HP V6 Outboards (Replaces 75692Q2, 75692T)","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 aftermarket \u003cstrong\u003eThermostat Kit (143°F\/62°C)\u003c\/strong\u003e is engineered to fit a range of Mercury Marine V6 outboards, including 135-150 HP models (S\/N A904646 and newer), 175 HP models (S\/N C100861 and newer), and 200 HP models (S\/N 6435503 and newer).\u003c\/p\u003e\n\u003cp\u003eIt serves as a direct cross-reference for multiple OEM and aftermarket part numbers, including Mercury 75692Q2, Sierra 18-3553, and GLM 13340, ensuring a precise fit and function.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eDesigned for simple, direct replacement installation in the factory housing.\u003c\/li\u003e\n\u003cli\u003eMaintains engine temperature at a consistent 143°F (62°C) for optimal fuel efficiency and performance.\u003c\/li\u003e\n\u003cli\u003eThe kit includes two thermostats and four gaskets, providing everything needed for a complete service.\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 brands.\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\u003eMercury\u003c\/td\u003e\n\u003ctd\u003e75692Q2\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMercury\u003c\/td\u003e\n\u003ctd\u003e75692T\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMercury\u003c\/td\u003e\n\u003ctd\u003e75692\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-3553\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-3543\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eGLM\u003c\/td\u003e\n\u003ctd\u003e13340\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eGLM\u003c\/td\u003e\n\u003ctd\u003e13010\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMallory\u003c\/td\u003e\n\u003ctd\u003e9-60002\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMallory\u003c\/td\u003e\n\u003ctd\u003e9-43019\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 and year\/serial number in the table below to ensure correct fitment.\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\u003eMercury\u003c\/td\u003e\n        \u003ctd\u003eV6 Outboards\u003c\/td\u003e\n        \u003ctd\u003e135-150\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003eS\/N A904646+\u003c\/td\u003e\n        \u003ctd\u003e75692Q2\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\u003c\/td\u003e\n        \u003ctd\u003eV6 Outboards\u003c\/td\u003e\n        \u003ctd\u003e175\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003eS\/N C100861+\u003c\/td\u003e\n        \u003ctd\u003e75692Q2\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\u003c\/td\u003e\n        \u003ctd\u003eV6 Outboards\u003c\/td\u003e\n        \u003ctd\u003e200\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003eS\/N 6435503+\u003c\/td\u003e\n        \u003ctd\u003e75692Q2\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\u003c\/td\u003e\n        \u003ctd\u003eBlack Max\u003c\/td\u003e\n        \u003ctd\u003e150\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1987+\u003c\/td\u003e\n        \u003ctd\u003e75692Q2\u003c\/td\u003e\n        \u003ctd\u003eConfirmed fit\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\u003c\/td\u003e\n        \u003ctd\u003eXR6\u003c\/td\u003e\n        \u003ctd\u003e150\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e2001+\u003c\/td\u003e\n        \u003ctd\u003e75692Q2\u003c\/td\u003e\n        \u003ctd\u003eConfirmed fit\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 Kit\u003c\/dd\u003e\n  \u003cdt\u003eInstallation\u003c\/dt\u003e\n\u003cdd\u003eDirect replacement\u003c\/dd\u003e\n  \u003cdt\u003eTemperature Rating\u003c\/dt\u003e\n\u003cdd\u003e143°F (62°C)\u003c\/dd\u003e\n  \u003cdt\u003eMaterial\u003c\/dt\u003e\n\u003cdd\u003eMetal with rubber gasket seals\u003c\/dd\u003e\n  \u003cdt\u003eQuantity\u003c\/dt\u003e\n\u003cdd\u003eKit of 2 thermostats with 4 gaskets (2 per thermostat)\u003c\/dd\u003e\n  \u003cdt\u003eCompatibility\u003c\/dt\u003e\n\u003cdd\u003eMercury Marine V6 Outboards\u003c\/dd\u003e\n  \u003cdt\u003eApplication\u003c\/dt\u003e\n\u003cdd\u003eMarine outboard cooling system\u003c\/dd\u003e\n  \u003cdt\u003eNotes\u003c\/dt\u003e\n\u003cdd\u003eWill not fit DFI Optimax motors\u003c\/dd\u003e\n  \u003cdt\u003eWarranty\u003c\/dt\u003e\n\u003cdd\u003eVaries by seller (typically 90 days)\u003c\/dd\u003e\n\u003c\/dl\u003e\n\n\u003ch2\u003eWhat’s in the Box\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cspan style=\"color:#d0021b;\"\u003e2 x\u003c\/span\u003e Thermostat (Replaces 75692Q2)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cspan style=\"color:#d0021b;\"\u003e4 x\u003c\/span\u003e Rubber Gasket Seals\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n  \u003cli\u003eDisconnect the negative battery cable before starting work.\u003c\/li\u003e\n  \u003cli\u003eAllow the engine to cool completely. Loosen the pressure cap to release any residual pressure.\u003c\/li\u003e\n  \u003cli\u003ePartially drain the engine coolant until the level is below the thermostat housing.\u003c\/li\u003e\n  \u003cli\u003eRemove the bolts securing the thermostat housing cover.\u003c\/li\u003e\n  \u003cli\u003eCarefully remove the old thermostat and gasket. Note the orientation of the thermostat.\u003c\/li\u003e\n  \u003cli\u003eThoroughly clean all gasket mating surfaces on the housing and cover.\u003c\/li\u003e\n  \u003cli\u003eInstall the new thermostat and gasket, ensuring it is seated correctly in the housing.\u003c\/li\u003e\n  \u003cli\u003eReinstall the cover and tighten the bolts to the manufacturer’s specified torque.\u003c\/li\u003e\n  \u003cli\u003eRefill the cooling system with the appropriate coolant mixture.\u003c\/li\u003e\n  \u003cli\u003eReconnect the battery, start the engine, and check for any leaks as it warms up to operating temperature.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow do I confirm this thermostat fits my engine?\u003c\/summary\u003e\n  \u003cp\u003eVerify your engine's model and serial number against the compatibility table. This kit fits specific Mercury V6 outboards, including 135\/150 HP (S\/N A904646+), 175 HP (S\/N C100861+), and 200 HP (S\/N 6435503+). Please note, it will not fit DFI Optimax motors.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat are the signs of a failing thermostat?\u003c\/summary\u003e\n  \u003cp\u003eCommon symptoms include engine overheating, the engine not reaching its proper operating temperature (running too cool), or erratic fluctuations on your temperature gauge. A stuck-open or stuck-closed thermostat can cause these issues.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eDo I need to purchase gaskets separately?\u003c\/summary\u003e\n  \u003cp\u003eNo, this is a complete kit. It comes with two thermostats and four new rubber gasket seals, providing all the necessary components for a full replacement on a V6 engine.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat is the recommended replacement schedule for thermostats?\u003c\/summary\u003e\n  \u003cp\u003eFor preventative maintenance, it is advisable to inspect thermostats during annual service and replace them every 2-3 years, or approximately 300 hours of use. This can vary based on operating conditions, especially in saltwater environments.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eIs there a difference between this aftermarket kit and the OEM version?\u003c\/summary\u003e\n  \u003cp\u003eThis is an aftermarket replacement part designed to meet or exceed OEM specifications for fit, form, and function. While the OEM kit costs significantly more, our kit provides a reliable, cost-effective solution without compromising on quality materials or performance.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhy does the kit include two thermostats?\u003c\/summary\u003e\n  \u003cp\u003eThe specified Mercury V6 engines use two thermostats as part of their cooling system design. This kit provides both units required for a complete and balanced replacement service.\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 and specifications against your original part before purchasing. If anything differs—even if your model appears compatible—do not purchase.\u003c\/li\u003e\n  \u003cli\u003eThis is an aftermarket replacement component, not an original equipment manufacturer (OEM) part.\u003c\/li\u003e\n  \u003cli\u003eProfessional installation is highly recommended for safety, proper function, and to prevent engine damage.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePro-Grade Standards\u003c\/strong\u003e — We supply marine parts engineered to OEM-level tolerances and rigorously tested for real-world reliability.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFast Global Fulfillment\u003c\/strong\u003e — We offer free standard delivery to most regions with an average transit time of 5–15 days.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer-Direct Value\u003c\/strong\u003e — By working directly with manufacturers, we provide fair pricing without compromising on materials or quality control.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50718268653883,"sku":"GH-TH20005-M","price":19.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/GH-TH20005-M.png?v=1762958639","url":"https:\/\/seasierra.com\/products\/thermostat-kit-143-f-62-c-fits-mercury-marine-135-200-hp-v6-outboards-replaces-75692q2-75692t","provider":"SeaSierra","version":"1.0","type":"link"}