{"product_id":"mercury-20-30-hp-300-hour-service-kit-8m0120839-s-n-0r106999-above","title":"Mercury – 300 Hour Maintenance Kit | FourStroke Service Package | Complete Engine Care Components | 8M0120839","description":"\u003cp\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eMercury – 300 Hour Maintenance Kit | FourStroke Service Package | Complete Engine Care Components | 8M0120839\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eOverview\u003c\/span\u003e\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003eThere’s a certain kind of confidence you get when you know your outboard is properly cared for—the kind that lets you run a little farther, stay a little longer, and push through whatever the day brings. When you’re depending on a 25–30 horsepower Mercury FourStroke, that confidence comes from routine upkeep done the right way. The Mercury 8M0120839 300 Hour Maintenance Kit delivers exactly that feeling.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003eInstead of gathering parts piece by piece, this kit puts every essential component for your 300-hour service into one clean, complete package. It’s built for boaters who want their engine to start quickly, idle smoothly, and keep climbing through the powerband without hesitation. Whether you fish the marshes before dawn or cruise the lake with the family on weekends, this kit helps keep your engine performing with the same steady reliability you’ve come to expect.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eKey Features\u003c\/span\u003e\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eComplete 300-hour service kit for Mercury 25–30hp FourStroke outboards.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eIncludes oil filter, fuel filter, spark plugs (three), oil drain seal, thermostat and gaskets, gearcase seals, unit anode, and water pump impeller kit.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eHigh-pleat oil and fuel filters deliver superior filtration for cleaner, healthier engine operation.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eHeavy-duty electroplated housings resist corrosion in harsh marine environments.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003ePrecision-built components engineered to exact Mercury Marine specifications.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eWorks seamlessly with Mercury 4-Stroke Marine Engine Oil and Premium Gear Lube (sold separately).\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eEngine \u0026amp; Boat Compatibility\u003c\/span\u003e\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eFits Mercury 25–30hp FourStroke outboards\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eFor engines within serial numbers 0R106999 through 1R162636\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan data-preserver-spaces=\"true\"\u003eIdeal for ski\u003c\/span\u003e\u003cspan data-preserver-spaces=\"true\"\u003effs, jon boats, inflatable tenders, aluminum fishing rigs, and utility boats\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eSuitable for freshwater and coastal boating environments\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003ePerformance \u0026amp; Practical Benefits\u003c\/span\u003e\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003eA 300-hour service can completely refresh the way your engine runs. Clean filters help fuel and oil move freely, giving you stronger throttle response and smoother mid-range power. New spark plu\u003c\/span\u003e\u003cspan data-preserver-spaces=\"true\"\u003egs bring back that crisp, easy starting you remember from the first day you ran the engine.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003eThe impeller replacement is one of the most important steps in the service. A strong, healthy water pump keeps temperatures stable so your engine stays protected even during long idles, extended trolling runs, or full-throttle stretches across open water. Fresh gearcase seals add another layer of defense by reducing the likelihood of water intrusion, helping gears and bearings last longer.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003eEvery part in this kit works together to give you that tight, steady, trustworthy running quality Mercury FourStrokes are known for. When your maintenance is done right, you feel it every time you leave the dock.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eWhy Buy OEM\u003c\/span\u003e\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cspan data-preserver-spaces=\"true\"\u003eG\u003c\/span\u003e\u003cspan data-preserver-spaces=\"true\"\u003eenuine Mercury parts ensure exact fit and consistent performance\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eDesigned specifically for your 25–30hp FourStroke—no guessing, no mismatches\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eMore durable and reliable than many aftermarket alternatives\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eHelps preserve engine life and protect your investment\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan data-preserver-spaces=\"true\"\u003eBacked by decades of Mercury Marine engineering and testing\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003eSe\u003c\/span\u003e\u003cspan data-preserver-spaces=\"true\"\u003easoned boaters will tell you the same thing: OEM parts simply hold up better, especially when your engine earns its hours in real-world conditions.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eFAQ\u003c\/span\u003e\u003c\/strong\u003e\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eQ1: Which engines does the 8M0120839 kit fit?\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003e It fits Mercury 25–30hp FourStroke outboards within serial numbers 0R106999–1R162636.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eQ2: How is this different from aftermarket kits?\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003e Mercury filters, seals, and components are engineered to tighter tolerances and built for long-term marine durability.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eQ3: How do I confirm this is the right kit for my outboard?\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003e Check your engine’s serial number and match it to the supported range.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eQ4: Can this kit be used in saltwater and freshwater?\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003e Yes—every part is designed to handle both environments.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan data-preserver-spaces=\"true\"\u003eQ5: Is the 300-hour service manageable for most boat owners?\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan data-preserver-spaces=\"true\"\u003e If you’re comfortable with routine maintenance, yes. Otherwise, any Mercury dealer can perform the service.\u003c\/span\u003e\u003c\/p\u003e","brand":"Mercury","offers":[{"title":"Default Title","offer_id":45626597507363,"sku":"8M0120839","price":277.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0783\/7410\/9475\/files\/8M0120839_Main.jpg?v=1760631384","url":"https:\/\/partsvu.com\/en-mx\/products\/mercury-20-30-hp-300-hour-service-kit-8m0120839-s-n-0r106999-above","provider":"PartsVu","version":"1.0","type":"link"}