{"product_id":"mercruiser-thermostat-kit-807252t4","title":"MerCruiser Thermostat Kit – 807252T4","description":"\u003cp data-start=\"83\" data-end=\"466\"\u003eThe Mercury MerCruiser Thermostat Kit 807252T4 is a genuine OEM thermostat service kit designed for GM-based V6 and V8 MerCruiser engines using closed cooling (freshwater cooling) systems. This kit is calibrated for higher operating temperatures than raw water systems, allowing engines to run more efficiently while maintaining proper internal clearances and combustion performance.\u003c\/p\u003e\n\u003cp data-start=\"468\" data-end=\"749\"\u003eThis thermostat is typically rated at \u003cstrong data-start=\"506\" data-end=\"521\"\u003e170°F–180°F\u003c\/strong\u003e, making it correct for engines equipped with heat exchangers. The kit includes the thermostat along with required seals and gaskets for a complete service, ensuring proper sealing and consistent coolant flow through the system.\u003c\/p\u003e\n\u003chr data-start=\"751\" data-end=\"754\"\u003e\n\u003ch3 data-start=\"756\" data-end=\"772\"\u003eKey Features\u003c\/h3\u003e\n\u003cul data-start=\"773\" data-end=\"1115\"\u003e\n\u003cli data-start=\"773\" data-end=\"825\"\u003eGenuine Mercury MerCruiser \/ Quicksilver OEM kit\u003c\/li\u003e\n\u003cli data-start=\"826\" data-end=\"889\"\u003eDesigned for \u003cstrong data-start=\"841\" data-end=\"887\"\u003eclosed cooling (freshwater cooled) systems\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"890\" data-end=\"948\"\u003eHigher temperature rating (typically 170°–180°F range)\u003c\/li\u003e\n\u003cli data-start=\"949\" data-end=\"1005\"\u003eIncludes thermostat, seals, and installation gaskets\u003c\/li\u003e\n\u003cli data-start=\"1006\" data-end=\"1059\"\u003eDirect OEM replacement — no modification required\u003c\/li\u003e\n\u003cli data-start=\"1060\" data-end=\"1115\"\u003eMaintains optimal engine temperature and efficiency\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr data-start=\"1117\" data-end=\"1120\"\u003e\n\u003ch3 data-start=\"1122\" data-end=\"1146\"\u003eEngine Compatibility\u003c\/h3\u003e\n\u003cp data-start=\"1147\" data-end=\"1217\"\u003eFits GM-based MerCruiser engines equipped with closed cooling systems:\u003c\/p\u003e\n\u003cul data-start=\"1219\" data-end=\"1326\"\u003e\n\u003cli data-start=\"1219\" data-end=\"1254\"\u003e4.3L V6 (closed cooling models)\u003c\/li\u003e\n\u003cli data-start=\"1255\" data-end=\"1272\"\u003e5.0L V8 (305)\u003c\/li\u003e\n\u003cli data-start=\"1273\" data-end=\"1290\"\u003e5.7L V8 (350)\u003c\/li\u003e\n\u003cli data-start=\"1291\" data-end=\"1308\"\u003e7.4L V8 (454)\u003c\/li\u003e\n\u003cli data-start=\"1309\" data-end=\"1326\"\u003e8.2L V8 (502)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-start=\"1328\" data-end=\"1349\"\u003eApplications include:\u003c\/p\u003e\n\u003cul data-start=\"1350\" data-end=\"1460\"\u003e\n\u003cli data-start=\"1350\" data-end=\"1401\"\u003eMerCruiser Bravo sterndrive with closed cooling\u003c\/li\u003e\n\u003cli data-start=\"1402\" data-end=\"1460\"\u003eMerCruiser inboard engines with heat exchanger systems\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-start=\"1462\" data-end=\"1566\"\u003e✔ Specifically for \u003cstrong data-start=\"1481\" data-end=\"1518\"\u003efreshwater\/closed cooling systems\u003c\/strong\u003e\u003cbr data-start=\"1518\" data-end=\"1521\"\u003e✔ Not for standard raw water cooled engines\u003c\/p\u003e\n\u003chr data-start=\"1568\" data-end=\"1571\"\u003e\n\u003ch3 data-start=\"1573\" data-end=\"1605\"\u003eSerial Number Fitment Notice\u003c\/h3\u003e\n\u003cp data-start=\"1606\" data-end=\"1825\"\u003eFitment varies by engine serial number and cooling configuration. Always confirm using your engine serial number before ordering. Engines converted from raw water to closed cooling may require different thermostat kits.\u003c\/p\u003e\n\u003chr data-start=\"1827\" data-end=\"1830\"\u003e\n\u003ch3 data-start=\"1832\" data-end=\"1868\"\u003eWhen This Part Needs Replacement\u003c\/h3\u003e\n\u003cul data-start=\"1869\" data-end=\"2098\"\u003e\n\u003cli data-start=\"1869\" data-end=\"1910\"\u003eEngine running too hot or overheating\u003c\/li\u003e\n\u003cli data-start=\"1911\" data-end=\"1960\"\u003eEngine not maintaining consistent temperature\u003c\/li\u003e\n\u003cli data-start=\"1961\" data-end=\"2005\"\u003eThermostat sticking or corrosion present\u003c\/li\u003e\n\u003cli data-start=\"2006\" data-end=\"2043\"\u003eCooling system service or rebuild\u003c\/li\u003e\n\u003cli data-start=\"2044\" data-end=\"2098\"\u003ePreventative maintenance on closed cooling systems\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr data-start=\"2100\" data-end=\"2103\"\u003e\n\u003ch3 data-start=\"2105\" data-end=\"2127\"\u003eInstallation Notes\u003c\/h3\u003e\n\u003cul data-start=\"2128\" data-end=\"2431\"\u003e\n\u003cli data-start=\"2128\" data-end=\"2190\"\u003eReplace all included gaskets and seals during installation\u003c\/li\u003e\n\u003cli data-start=\"2191\" data-end=\"2263\"\u003eEnsure thermostat orientation is correct (spring side toward engine)\u003c\/li\u003e\n\u003cli data-start=\"2264\" data-end=\"2313\"\u003eClean housing and sealing surfaces thoroughly\u003c\/li\u003e\n\u003cli data-start=\"2314\" data-end=\"2374\"\u003eInspect heat exchanger and coolant passages for blockage\u003c\/li\u003e\n\u003cli data-start=\"2375\" data-end=\"2431\"\u003eVerify coolant condition and replace if contaminated\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr data-start=\"2433\" data-end=\"2436\"\u003e\n\u003ch3 data-start=\"2438\" data-end=\"2495\"\u003eAlternate \/ Superseded \/ Cross-Reference Part Numbers\u003c\/h3\u003e\n\u003cul data-start=\"2496\" data-end=\"2696\"\u003e\n\u003cli data-start=\"2496\" data-end=\"2531\"\u003eMercury \/ Quicksilver: 807252T4\u003c\/li\u003e\n\u003cli data-start=\"2532\" data-end=\"2576\"\u003eSupersedes \/ Related: 807252T3, 807252Q4\u003c\/li\u003e\n\u003cli data-start=\"2577\" data-end=\"2596\"\u003eSierra: 18-3648\u003c\/li\u003e\n\u003cli data-start=\"2597\" data-end=\"2628\"\u003eEMP: Equivalent to 807252Q4\u003c\/li\u003e\n\u003cli data-start=\"2629\" data-end=\"2696\"\u003eThermostat (internal): Higher temp variant (approx. 170°–180°F)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr data-start=\"2698\" data-end=\"2701\"\u003e\n\u003ch3 data-start=\"2703\" data-end=\"2725\"\u003eParts Desk Insight\u003c\/h3\u003e\n\u003cp data-start=\"2726\" data-end=\"3087\"\u003eThis kit is commonly used on MerCruiser engines equipped with closed cooling systems where higher operating temperatures improve efficiency and reduce internal wear. A common mistake is installing a 160°F thermostat (raw water version) into a closed cooling engine — this will cause improper engine operation. Always confirm cooling system type before ordering.\u003c\/p\u003e\n\u003chr data-start=\"3089\" data-end=\"3092\"\u003e\n\u003ch3 data-start=\"3094\" data-end=\"3106\"\u003eShipping\u003c\/h3\u003e\n\u003cp data-start=\"3107\" data-end=\"3172\" data-is-last-node=\"\" data-is-only-node=\"\"\u003eShipping: Ships same or next day for fast Canada wide shipping. ⚓\u003c\/p\u003e","brand":"MERC","offers":[{"title":"Default Title","offer_id":43563879170084,"sku":"807252T4","price":99.93,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0743\/5799\/7604\/files\/f18ecfdf-968d-47e0-b460-9d3954d983d3.png?v=1774392736","url":"https:\/\/marisolmarine.com\/products\/mercruiser-thermostat-kit-807252t4","provider":"Marisol Marine Company","version":"1.0","type":"link"}