{"product_id":"merc-588","title":"Mercury MerCruiser Quicksilver Thermostat Housing Gasket 806871","description":"\u003cp\u003eMercury MerCruiser Quicksilver \u003cstrong\u003e27-806871\u003c\/strong\u003e is a thermostat housing gasket used on select MerCruiser gasoline engines. It seals the thermostat housing area to help control coolant flow and prevent leaks around the thermostat assembly. Mercury parts references show \u003cstrong\u003e806871\u003c\/strong\u003e as superseded, with current diagram references commonly listing \u003cstrong\u003e8M0238323\u003c\/strong\u003e and earlier replacement references showing \u003cstrong\u003e8M0204687\u003c\/strong\u003e as the functional replacement.\u003c\/p\u003e\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eGenuine Mercury \/ Quicksilver thermostat housing gasket reference\u003c\/li\u003e\n\u003cli\u003eUsed in select MerCruiser standard cooling system and thermostat housing assemblies\u003c\/li\u003e\n\u003cli\u003eHelps seal the thermostat housing during cooling-system service\u003c\/li\u003e\n\u003cli\u003eOriginal Mercury reference: \u003cstrong\u003e27-806871 \/ 806871\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli\u003eReplacement references include \u003cstrong\u003e27-8M0204687\u003c\/strong\u003e and \u003cstrong\u003e27-8M0238323\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli\u003eGTIN reference for 806871 \/ 8M0204687: \u003cstrong\u003e745061284968\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli\u003eCatalog shipping reference for 8M0204687: approximately \u003cstrong\u003e0.02 lb\u003c\/strong\u003e, \u003cstrong\u003e2.00 in. x 2.00 in. x 0.20 in.\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eEngine Compatibility\u003c\/h2\u003e\n\u003cp\u003eThis gasket is commonly shown for select MerCruiser gasoline engines, including many \u003cstrong\u003e3.0L GM 181 I\/L4\u003c\/strong\u003e, \u003cstrong\u003e4.3L V6\u003c\/strong\u003e, \u003cstrong\u003e5.0L \/ 5.7L GM V8\u003c\/strong\u003e, \u003cstrong\u003e6.2L\u003c\/strong\u003e, \u003cstrong\u003e7.4L\u003c\/strong\u003e, \u003cstrong\u003e8.2L\u003c\/strong\u003e, Black Scorpion, Scorpion, MAG, MPI, Alpha, Bravo, and inboard applications depending on serial number and thermostat housing design. Cross-reference descriptions also identify this gasket for V6 and V8 MerCruiser stern drive and inboard engines using the newer-style thermostat housing, plus select 4.5L MPI and 6.2L MPI applications by serial range.\u003c\/p\u003e\n\u003ch2\u003eSerial Number Fitment Notice\u003c\/h2\u003e\n\u003cp\u003eThermostat housing gasket fitment depends on the exact engine model, cooling-system layout, thermostat housing style, and serial number range. Always confirm compatibility using the MerCruiser engine serial number before ordering, especially where \u003cstrong\u003e27-806871\u003c\/strong\u003e has been replaced by newer references such as \u003cstrong\u003e27-8M0204687\u003c\/strong\u003e or \u003cstrong\u003e27-8M0238323\u003c\/strong\u003e.\u003c\/p\u003e\n\u003ch2\u003eWhen This Part Needs Replacement\u003c\/h2\u003e\n\u003cp\u003eReplace this gasket whenever the thermostat housing is removed, during thermostat replacement, or when there are signs of coolant leakage, gasket swelling, tearing, compression, corrosion marks, or seepage around the housing. Reusing an old thermostat housing gasket can cause a small leak that turns into repeat cooling-system service.\u003c\/p\u003e\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003cp\u003eClean both thermostat housing mating surfaces before installation and remove old gasket material carefully without gouging the housing. Inspect the thermostat, sleeve, lower housing gasket, plugs, hoses, clamps, and related cooling-system hardware while the housing is apart. Install using the correct orientation and follow the Mercury service manual torque procedure for the specific engine.\u003c\/p\u003e\n\u003ch2\u003eAlternate \/ Superseded Part Numbers\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e27-806871\u003c\/li\u003e\n\u003cli\u003e806871\u003c\/li\u003e\n\u003cli\u003e27-806871Q\u003c\/li\u003e\n\u003cli\u003e806871Q\u003c\/li\u003e\n\u003cli\u003e27-8M0204687\u003c\/li\u003e\n\u003cli\u003e8M0204687\u003c\/li\u003e\n\u003cli\u003e27-8M0238323\u003c\/li\u003e\n\u003cli\u003e8M0238323\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eParts Desk Insight\u003c\/h2\u003e\n\u003cp\u003eThis gasket is best matched by thermostat housing style, not just engine size. MerCruiser used different cooling-system layouts across similar-looking engines, so checking the serial-number diagram before ordering is the safest way to avoid getting the wrong thermostat gasket.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eShipping:\u003c\/strong\u003e Ships same or next day for fast Canada wide shipping. ⚓\u003c\/p\u003e","brand":"MERC","offers":[{"title":"Default Title","offer_id":43563878613028,"sku":"806871","price":13.98,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0743\/5799\/7604\/files\/s-l1200_2.jpg?v=1777485791","url":"https:\/\/marisolmarine.com\/products\/merc-588","provider":"Marisol Marine Company","version":"1.0","type":"link"}