{"product_id":"mercury-engine-coolant-4-877770k1","title":"Mercury – Extended Life Coolant \/ Anti-Freeze | Closed Cooling System Care | Pre-Diluted 50\/50 | 877770K1","description":"\u003ch2\u003e\u003cspan data-preserver-spaces=\"true\"\u003eMercury – Extended Life Coolant \/ Anti-Freeze | Closed Cooling System Care | Pre-Diluted 50\/50 | 877770K1\u003c\/span\u003e\u003c\/h2\u003e\n\u003ch3\u003e\u003cspan data-preserver-spaces=\"true\"\u003eOverview\u003c\/span\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003eEvery seasoned boater knows the quiet kind of confidence that comes from lifting the engine hatch and seeing a cooling system you can trust. When you’re running a MerCruiser inboard or sterndrive with closed cooling, you rely on that system to keep temperatures steady whether you’re idling through the no-wake zone or pushing hard across open water. Mercury’s 877770K1 Extended Life Coolant delivers that peace of mind. It protects the engine you depend on, keeps scale from building up, and maintains consistent temperatures without you having to think twice. It’s one of those behind-the-scenes essentials that makes your whole boating season feel smoother.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cspan data-preserver-spaces=\"true\"\u003eKey Features\u003c\/span\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eFormulated for all MerCruiser closed-cooling gasoline engines\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003ePre-diluted 50\/50 mix with de-ionized water\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eProvides up to 5 years or 1,000 operating hours of protection\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eEthylene glycol based for reliable freeze and boil-over protection\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eOffers freeze protection down to –34°F and boiling protection up to 265°F\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eWill not cause coolant gelling\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eMeets ASTM D-3306 and D-4340 requirements\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cspan data-preserver-spaces=\"true\"\u003eEngine \u0026amp; Boat Compatibility\u003c\/span\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eAll MerCruiser gasoline engines with closed-cooling systems\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eSterndrive and inboard applications\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eIdeal for cruisers, cabin boats, sport boats, tow boats, and larger runabouts\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cspan data-preserver-spaces=\"true\"\u003ePerformance \u0026amp; Practical Benefits\u003c\/span\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003eWhen you’re cruising on a hot day, the last thing you want is temperature creep or cooling issues. This coolant maintains a stable thermal environment, helping your engine operate smoothly even under heavier loads. \u003c\/span\u003e\u003cspan data-preserver-spaces=\"true\"\u003eThe extended-life formulation reduces the buildup of deposits, helping water passages stay open and efficient. You’ll notice steadier gauge readings and fewer fluctuations during long runs.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003eBecause it’s pre-mixed, there’s no measuring, guessing, or worrying about tap-water minerals getting into your system. You pour it in, and it’s instantly ready to protect. Whether you store your boat in cold climates or run hard in warm ones, the deep freeze and high-heat protection make a difference you can genuinely feel.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cspan data-preserver-spaces=\"true\"\u003eWhy Buy OEM\u003c\/span\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003eWith something as critical as cooling, shortcuts just aren’t worth it. Mercury’s extended life coolant is built around the operating needs of MerCruiser engines — not a generic automotive standard. That means better compatibility, better corrosion resistance, and fewer headaches down the road.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003eYou get longer service intervals, cleaner internals, and a system that simply behaves the way it should. It’s the sort of practical choice every experienced boater makes when reliability matters more than anything else.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cspan data-preserver-spaces=\"true\"\u003eFAQ\u003c\/span\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eQ1: What engines is this coolant designed for?\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003e Any MerCruiser gasoline engine equipped with a closed-cooling system.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eQ2: Can I mix it with traditional automotive coolant?\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003e It’s technically compatible, but doing so reduces the extended-life benefits.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eQ3: How do I know this is the right coolant for my boat?\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003e If your MerCruiser uses closed cooling, this is the OEM-specified formula.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eQ4: Does it work in extreme cold?\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003e Yes — it protects down to –34°F.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eQ5: Is it premixed and ready to use?\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003e Yes, it’s a 50\/50 pre-diluted blend with de-ionized water.\u003c\/span\u003e\u003c\/p\u003e","brand":"Mercury","offers":[{"title":"Default Title","offer_id":46933886206243,"sku":"92-877770K1","price":27.43,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0783\/7410\/9475\/files\/858023K01_Main.jpg?v=1760631278","url":"https:\/\/partsvu.com\/en-au\/products\/mercury-engine-coolant-4-877770k1","provider":"PartsVu","version":"1.0","type":"link"}