{"product_id":"coil-kit-339-856991a1","title":"Mercury – Ignition Coil for 2-Stroke Outboards | Ignition System Component | Resin-Insulated Construction | 856991A1","description":"\u003cp data-start=\"0\" data-end=\"132\"\u003e\u003cstrong data-start=\"0\" data-end=\"132\"\u003eMercury – Ignition Coil for 2-Stroke Outboards | Ignition System Component | Resin-Insulated Construction | 856991A1\u003c\/strong\u003e\u003c\/p\u003e\n\u003chr data-start=\"134\" data-end=\"137\"\u003e\n\u003cp data-start=\"139\" data-end=\"721\"\u003e\u003cstrong data-start=\"139\" data-end=\"151\"\u003eOverview\u003c\/strong\u003e\u003cbr data-start=\"151\" data-end=\"154\"\u003eThere’s a certain comfort that comes from turning the key and hearing your engine fire instantly, no hesitation, no struggle—just clean, confident ignition. When you’ve spent enough mornings pushing off the dock before sunrise or easing back toward shore after a long day on the water, you learn to appreciate the parts that make those moments effortless. The Mercury Marine part number 856991A1 Ignition Coil is one of those parts. It delivers the kind of steady spark that keeps a 2-stroke outboard feeling lively, responsive, and ready for whatever the day brings.\u003c\/p\u003e\n\u003chr data-start=\"723\" data-end=\"726\"\u003e\n\u003cp data-start=\"728\" data-end=\"746\"\u003e\u003cstrong data-start=\"728\" data-end=\"744\"\u003eKey Features\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"747\" data-end=\"1131\"\u003e\n\u003cli data-start=\"747\" data-end=\"832\"\u003e\n\u003cp data-start=\"749\" data-end=\"832\"\u003eDelivers a strong, consistent spark to support smooth engine starting and running\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"833\" data-end=\"912\"\u003e\n\u003cp data-start=\"835\" data-end=\"912\"\u003eResin-insulated internal construction for moisture and vibration resistance\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"913\" data-end=\"972\"\u003e\n\u003cp data-start=\"915\" data-end=\"972\"\u003eProduced to Mercury Marine original equipment standards\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"973\" data-end=\"1048\"\u003e\n\u003cp data-start=\"975\" data-end=\"1048\"\u003eDesigned for use on a variety of Mercury and Mariner 2-stroke outboards\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1049\" data-end=\"1131\"\u003e\n\u003cp data-start=\"1051\" data-end=\"1131\"\u003eEngineered for dependable ignition performance across all operating conditions\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr data-start=\"1133\" data-end=\"1136\"\u003e\n\u003cp data-start=\"1138\" data-end=\"1171\"\u003e\u003cstrong data-start=\"1138\" data-end=\"1169\"\u003eEngine \u0026amp; Boat Compatibility\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul data-start=\"1172\" data-end=\"1524\"\u003e\n\u003cli data-start=\"1172\" data-end=\"1248\"\u003e\n\u003cp data-start=\"1174\" data-end=\"1248\"\u003eWorks with a wide range of Mercury and Mariner 2-stroke outboard engines\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1249\" data-end=\"1360\"\u003e\n\u003cp data-start=\"1251\" data-end=\"1360\"\u003eSuitable for horsepower ranges commonly used on fishing boats, pontoon boats, runabouts, and utility skiffs\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1361\" data-end=\"1442\"\u003e\n\u003cp data-start=\"1363\" data-end=\"1442\"\u003eCompatible with select MerCruiser sterndrives that specify this ignition coil\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"1443\" data-end=\"1524\"\u003e\n\u003cp data-start=\"1445\" data-end=\"1524\"\u003eIdeal for owners wanting direct-fit ignition performance without modification\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr data-start=\"1526\" data-end=\"1529\"\u003e\n\u003cp data-start=\"1531\" data-end=\"2039\"\u003e\u003cstrong data-start=\"1531\" data-end=\"1567\"\u003ePerformance \u0026amp; Practical Benefits\u003c\/strong\u003e\u003cbr data-start=\"1567\" data-end=\"1570\"\u003eA healthy ignition coil changes the entire personality of an engine. With the 856991A1 installed, you’ll notice a smoother, more confident engine start, even on those cool mornings when 2-strokes tend to grumble a bit. Once running, the coil delivers a tight, steady spark that helps the motor idle cleaner and respond better when you roll into the throttle. There’s no sputter, no weak firing—just a strong, balanced ignition pulse that keeps everything feeling crisp.\u003c\/p\u003e\n\u003cp data-start=\"2041\" data-end=\"2545\"\u003eIn real use, this coil shines in the moments where a lesser part would fall short: rough chop, sudden throttle changes, long idle periods, and damp conditions that would make lower-quality coils misfire. The resin-insulated internal design protects the coil from moisture, heat, and the constant vibration that comes with life on the transom. Installation is straightforward, thanks to the precise OEM fit. Once you bolt it down and reconnect your leads, it sits secure, with no play or alignment issues.\u003c\/p\u003e\n\u003cp data-start=\"2547\" data-end=\"2849\"\u003eDurability is another standout trait. Mercury builds this coil to endure the kind of conditions boaters actually face—wet hands, unexpected spray, long days of trolling, and the occasional jolt when you hit a bit of floating debris. It’s the kind of part you install once and trust for seasons to come.\u003c\/p\u003e\n\u003chr data-start=\"2851\" data-end=\"2854\"\u003e\n\u003cp data-start=\"2856\" data-end=\"3472\"\u003e\u003cstrong data-start=\"2856\" data-end=\"2871\"\u003eWhy Buy OEM\u003c\/strong\u003e\u003cbr data-start=\"2871\" data-end=\"2874\"\u003eIgnition systems aren’t a place to cut corners. A genuine Mercury Marine part like the 856991A1 is engineered specifically for the demands of 2-stroke outboards, with the right windings, insulation, and spark output. Aftermarket coils might look similar, but the performance gap usually shows up when you need reliability most—during hard acceleration, in wet conditions, or after hours of vibration. With OEM, you get proper fitment, long-term stability, and the confidence that you’re giving your engine the spark it was designed around. It’s smart, practical, and cost-effective in the long run.\u003c\/p\u003e\n\u003chr data-start=\"3474\" data-end=\"3477\"\u003e\n\u003cp data-start=\"3479\" data-end=\"3486\"\u003e\u003cstrong data-start=\"3479\" data-end=\"3486\"\u003eFAQ\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-start=\"3488\" data-end=\"3725\"\u003e\u003cstrong data-start=\"3488\" data-end=\"3554\"\u003eQ1: Which engines does the Mercury 856991A1 Ignition Coil fit?\u003c\/strong\u003e\u003cbr data-start=\"3554\" data-end=\"3557\"\u003eIt fits a variety of Mercury and Mariner 2-stroke outboards and select MerCruiser sterndrives. Checking your service manual or existing coil is the best way to confirm.\u003c\/p\u003e\n\u003cp data-start=\"3727\" data-end=\"3950\"\u003e\u003cstrong data-start=\"3727\" data-end=\"3788\"\u003eQ2: What makes this coil better than aftermarket options?\u003c\/strong\u003e\u003cbr data-start=\"3788\" data-end=\"3791\"\u003eIt’s built to Mercury Marine’s original equipment standards, offering stronger, more stable spark output and far better durability under real-world conditions.\u003c\/p\u003e\n\u003cp data-start=\"3952\" data-end=\"4138\"\u003e\u003cstrong data-start=\"3952\" data-end=\"4009\"\u003eQ3: How do I know if this is the correct replacement?\u003c\/strong\u003e\u003cbr data-start=\"4009\" data-end=\"4012\"\u003eIf your manual or existing part lists 856991A1, this is the correct coil. Matching part numbers is the simplest way to verify.\u003c\/p\u003e\n\u003cp data-start=\"4140\" data-end=\"4308\"\u003e\u003cstrong data-start=\"4140\" data-end=\"4198\"\u003eQ4: Can this coil be used in saltwater and freshwater?\u003c\/strong\u003e\u003cbr data-start=\"4198\" data-end=\"4201\"\u003eAbsolutely. The resin-insulated design protects it from moisture, corrosion, and heat in both environments.\u003c\/p\u003e\n\u003cp data-start=\"4310\" data-end=\"4487\"\u003e\u003cstrong data-start=\"4310\" data-end=\"4371\"\u003eQ5: Is installation straightforward for most boat owners?\u003c\/strong\u003e\u003cbr data-start=\"4371\" data-end=\"4374\"\u003eYes. If you’re comfortable replacing basic ignition components, this coil installs cleanly with a direct OEM fit.\u003c\/p\u003e","brand":"Mercury","offers":[{"title":"Default Title","offer_id":46940470968611,"sku":"339-856991A1","price":157.91,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0783\/7410\/9475\/files\/856991a1_main.jpg?v=1760631249","url":"https:\/\/partsvu.com\/en-au\/products\/coil-kit-339-856991a1","provider":"PartsVu","version":"1.0","type":"link"}