{"title":"4-Stroke 50HP Outboard Marine Engine","description":"\u003csection id=\"hero\" style=\"padding:16px;border:1px solid #e5e7eb;border-radius:8px;max-width:980px;margin:0 auto 20px auto;\"\u003e\n  \u003cp\u003eThis page focuses on Mercury 4-Stroke 50HP outboard engines and helps you find compatible parts and key service information. Below you’ll find maintenance tips, commonly replaced parts, and troubleshooting guidance. You can also browse the main Mercury collection for additional items. Scroll to the bottom of this page to start browsing parts for this engine, and remember that on the collection page you can use the Filter \u0026amp; Sort controls to narrow results by horsepower, year range, and part category.\u003c\/p\u003e\n  \u003cp\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-outboard-parts\" style=\"display:inline-block;padding:10px 14px;background:#0d6efd;color:#fff;text-decoration:none;border-radius:6px;\"\u003eBrowse All Mercury Parts\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"identify-model\" style=\"max-width:980px;margin:0 auto 20px auto;\"\u003e\n  \u003ch2\u003eHow to Identify Your 50HP Model\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eNameplate\/serial plate: Look on the transom bracket or swivel bracket for the serial number and model designation.\u003c\/li\u003e\n    \u003cli\u003eModel code and suffix: Codes such as “ELPT” indicate electric start, long shaft (20\"), power trim \u0026amp; tilt; “CT” denotes the Command Thrust gearcase. Suffixes can also identify tiller vs. remote control setups.\u003c\/li\u003e\n    \u003cli\u003e4-stroke identifiers: Oil fill cap and dipstick on the powerhead, EFI decals, and a cowling style typical of Mercury FourStroke models.\u003c\/li\u003e\n    \u003cli\u003eGearcase option: Some 50HP models use Command Thrust (CT) with a larger gearcase and different prop fitment compared with the standard gearcase.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"engine-overview\" style=\"max-width:980px;margin:0 auto 20px auto;\"\u003e\n  \u003ch2\u003eEngine Overview\u003c\/h2\u003e\n  \u003ch3\u003eMercury 50HP FourStroke EFI (Inline-4)\u003c\/h3\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eDescription\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eInline-4, EFI 4-stroke, SOHC with two valves per cylinder; thermostat-controlled cooling; through-prop exhaust.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eExamples include 50 EFI, 50 ELPT, and 50 ELPT CT (Command Thrust). Exact features vary by year and rigging.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eSmooth idle, good fuel economy, and strong low-end torque for heavier hulls or loaded boats. CT variants swing larger props for improved thrust.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eTypical WOT range is about 5000–6000 RPM depending on propeller. CT gearcases use different props and certain gearcase components compared with the standard version.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"service-kits\" style=\"max-width:980px;margin:0 auto 20px auto;\"\u003e\n  \u003ch2\u003eRoutine Maintenance \u0026amp; Service Parts\u003c\/h2\u003e\n  \u003cp\u003eIntervals below are general guidelines for a typical 4-stroke 50HP outboard. Always follow your specific Mercury service manual for procedures and exact schedules.\u003c\/p\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eItem\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eInterval*\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eRemarks\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eParts Link\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eEngine oil \u0026amp; filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eUse marine FC‑W oil (commonly 25W‑40) and replace the filter; warm engine before draining.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/oil-filters\"\u003eOil Filters\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eGear oil (lower unit)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eInspect drain screw magnets for metal; replace seals\/crush washers as needed.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-lower-unit-seal-kits\"\u003eMercury Lower Unit Seal Kits\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eSpark plugs\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eInspect at 100 hours; replace per manual\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eCheck gap and condition; replace if fouled or worn.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/spark-plug\"\u003eSpark Plugs\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eFuel filter \/ water separator\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eReplace inline\/engine filter; if equipped, service remote water-separating filter.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/fuel-filters-1\"\u003eFuel Filters\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eWater pump impeller\/kit\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eEvery 2–3 seasons or 200 hours (sooner for sandy\/silty use)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eCritical for cooling performance; replace housing and key if worn.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-water-pump-repair-kits\"\u003eMercury Water Pump Repair Kits\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eAnodes (zinc\/aluminum\/magnesium)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eInspect every 50 hours; replace when 50% depleted\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eChoose alloy based on water type (salt\/brackish\/fresh) and ensure good electrical contact.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/anodes\"\u003eAnodes\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"common-parts\" style=\"max-width:980px;margin:0 auto 20px auto;\"\u003e\n  \u003ch2\u003eFrequently Used Parts Categories\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eRoutine Service Kits – \u003ca href=\"https:\/\/seasierra.com\/collections\/service-maintenance-kits\"\u003eService \u0026amp; Maintenance Kits\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCooling System – \u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-water-pump-repair-kits\"\u003eMercury Water Pump Repair Kits\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eGearcase Seals – \u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-lower-unit-seal-kits\"\u003eMercury Lower Unit Seal Kits\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eFuel System Filtration – \u003ca href=\"https:\/\/seasierra.com\/collections\/fuel-filters-1\"\u003eFuel Filters\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eIgnition \u0026amp; Tune-Up – \u003ca href=\"https:\/\/seasierra.com\/collections\/spark-plug\"\u003eSpark Plugs\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003ePropellers \u0026amp; Hardware – \u003ca href=\"https:\/\/seasierra.com\/collections\/propellers\"\u003ePropellers\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eAccessories \u0026amp; Handling – \u003ca href=\"https:\/\/seasierra.com\/collections\/outboard-hydrofoil-stabilizers\"\u003eOutboard Hydrofoil Stabilizers\u003c\/a\u003e\n\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"troubleshooting\" style=\"max-width:980px;margin:0 auto 20px auto;\"\u003e\n  \u003ch2\u003eCommon Symptoms \u0026amp; Quick Checks\u003c\/h2\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eSymptom\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eCheck First\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eRelated Parts\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eWeak tell‑tale or overheat alarm\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eInspect water intake screens, tell‑tale hose for blockage, and impeller condition.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eWater pump kit, thermostat, intake screen\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eHard starting or rough idle\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eCheck battery voltage, fuel quality, and condition of plugs and filters.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eSpark plugs, fuel filter, starter (if cranking weak)\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003ePoor acceleration or power loss\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eVerify prop condition\/pitch, check for fouled plugs, restricted fuel flow, or hull growth.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003ePropeller, spark plugs, fuel filter\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eGearcase noise or metal in gear oil\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eDrain gear oil and inspect; check prop shaft for fishing line and seal damage.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f0f0;\"\u003eLower unit seal kit, prop hardware\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"faq\" style=\"max-width:980px;margin:0 auto 20px auto;\"\u003e\n  \u003ch2\u003eFAQs\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eAre parts interchangeable across all 50HP years and platforms?\u003c\/summary\u003e\n    \u003cp\u003eNot always. Standard vs. Command Thrust gearcases, control type (tiller vs. remote), and year-to-year updates can change part fitment. Confirm your model code and serial number before ordering.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhen should I replace the impeller?\u003c\/summary\u003e\n    \u003cp\u003eAs a rule of thumb, every 2–3 seasons or about 200 hours, and sooner if you operate in sandy, silty, or shallow environments. Replace the full kit if the housing shows wear.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow often should I change gear oil?\u003c\/summary\u003e\n    \u003cp\u003eTypically every 100 hours or annually. Inspect the drained oil for milkiness (water intrusion) or metal. If contamination is found, pressure\/vacuum test the gearcase and service seals.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat information helps confirm part compatibility?\u003c\/summary\u003e\n    \u003cp\u003eProvide the engine’s serial number, model code (e.g., ELPT or CT), shaft length, and a photo of the nameplate. If possible, include photos of the part you’re replacing.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"cta\" style=\"max-width:980px;margin:0 auto 24px auto;\"\u003e\n  \u003cp\u003eReady to find parts by horsepower, year, and model? Browse the main Mercury collection and use Filter \u0026amp; Sort to narrow to your 50HP FourStroke.\u003c\/p\u003e\n  \u003cp\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-outboard-parts\" style=\"display:inline-block;padding:10px 14px;background:#0d6efd;color:#fff;text-decoration:none;border-radius:6px;\"\u003eShop Mercury Outboard Parts\u003c\/a\u003e\u003c\/p\u003e\n  \u003cp style=\"color:#555;\"\u003eIf you’re unsure about your model, send us a photo of the nameplate and the part you need and we’ll help verify compatibility.\u003c\/p\u003e\n\u003c\/section\u003e","products":[{"product_id":"whale-tail-hydrofoil-stabilizer-fits-outboard-motors-stern-drives-40-300-hp-replaces-fo2003","title":"Whale Tail Hydrofoil Stabilizer for 40–300 HP Outboard Motors and Stern Drives","description":"\u003csection\u003e\n\u003c!-- 🔧 Table Styles (include only once per page) --\u003e\n\u003cstyle\u003e\n  .ss-table-wrap { overflow-x:auto; -webkit-overflow-scrolling:touch; }\n  table.ss-table { width:100%; border-collapse:collapse; min-width:640px; }\n  table.ss-table th, table.ss-table td {\n    padding:10px 12px; border:1px solid #e5e7eb; text-align:left; vertical-align:top;\n  }\n  table.ss-table th {\n    white-space:nowrap;\n    word-break:normal;\n    letter-spacing:normal;\n    font-weight:600;\n    background:#f8fafc;\n  }\n  @media (max-width:480px){\n    table.ss-table th, table.ss-table td { padding:8px 10px; font-size:14px; }\n  }\n\u003c\/style\u003e\n\n\u003ch2\u003eProduct Details\u003c\/h2\u003e\n\u003cp\u003eThis marine-grade reinforced PA66 nylon \u003cstrong\u003eWhale Tail Hydrofoil Stabilizer\u003c\/strong\u003e is designed for many 40–300 HP outboard motors and stern drives. By adding hydrodynamic lift at the stern, it can help improve low-speed handling, reduce porpoising, shorten time to plane, and help the boat remain on plane at lower speeds.\u003c\/p\u003e\n\u003cp\u003eThis is an aftermarket hydrofoil stabilizer referenced in some listings as a replacement for FO2003 and as a Whale Tail-style hydrofoil. Confirm the dimensions, mounting area, engine or drive configuration, and listed exceptions before ordering.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eDrill-and-bolt installation on the anti-cavitation plate; mounting hardware and a drill bit are included.\u003c\/li\u003e\n  \u003cli\u003eMade from reinforced, marine-grade PA66 nylon for strength, impact resistance, and corrosion resistance.\u003c\/li\u003e\n  \u003cli\u003eThe curved hydrofoil profile is intended to improve stern lift while helping manage drag and propeller-area turbulence.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Number References\u003c\/h2\u003e\n\u003cp\u003eThe references below are aftermarket or listing references and should not be treated as proof of fitment by themselves. Always compare the product dimensions and application requirements with your equipment.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Part Number References\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eReference\u003c\/th\u003e\n        \u003cth\u003eNumber or Description\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eAftermarket reference\u003c\/td\u003e\n        \u003ctd\u003eFO2003\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eProduct style\u003c\/td\u003e\n        \u003ctd\u003eWhale Tail Hydrofoil Stabilizer\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eEngine and Drive Compatibility\u003c\/h2\u003e\n\u003cp\u003eApplication depends on the shape and available mounting area of the anti-cavitation plate or drive. The following information describes the intended application range and important exclusions noted for this style of hydrofoil; it does not replace a dimensional fit check.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Engine and Drive Compatibility\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eBrand or Application\u003c\/th\u003e\n        \u003cth\u003eCompatibility\u003c\/th\u003e\n        \u003cth\u003eNotes\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eGeneral application\u003c\/td\u003e\n        \u003ctd\u003eMany 40–300 HP outboard motors and stern drives\u003c\/td\u003e\n        \u003ctd\u003eConfirm clearance, mounting surface, dimensions, and hardware requirements before installation.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eVolvo Penta\u003c\/td\u003e\n        \u003ctd\u003eSX-A, DPS, DPR, DPH, and 280\/290 series applications may be suitable\u003c\/td\u003e\n        \u003ctd\u003eSome installations may require longer bolts and 1-inch fender washers. Not recommended for Volvo Ocean Series XDP applications.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\u003c\/td\u003e\n        \u003ctd\u003eMany 40–300 HP applications\u003c\/td\u003e\n        \u003ctd\u003eNot recommended for Mercury 4-Stroke 40, 50, or 60 HP models and not for Mercury Bravo II.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eHonda\u003c\/td\u003e\n        \u003ctd\u003eMany 40–200 HP applications\u003c\/td\u003e\n        \u003ctd\u003eNot recommended for applications above 200 HP.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eMany 40–300 HP applications\u003c\/td\u003e\n        \u003ctd\u003eNot recommended for 350 HP applications.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003cdl\u003e\n  \u003cdt\u003eProduct Type\u003c\/dt\u003e\n  \u003cdd\u003eHydrofoil stabilizer\u003c\/dd\u003e\n  \u003cdt\u003eInstallation\u003c\/dt\u003e\n  \u003cdd\u003eFour-bolt installation; drilling required\u003c\/dd\u003e\n  \u003cdt\u003eMounting Location\u003c\/dt\u003e\n  \u003cdd\u003eAnti-cavitation plate or compatible stern-drive mounting surface\u003c\/dd\u003e\n  \u003cdt\u003eMaterial\u003c\/dt\u003e\n  \u003cdd\u003eReinforced PA66 nylon, marine-grade plastic\u003c\/dd\u003e\n  \u003cdt\u003eColor\u003c\/dt\u003e\n  \u003cdd\u003eBlue, silver, or red depending on the selected model or available version\u003c\/dd\u003e\n  \u003cdt\u003eDimensions\u003c\/dt\u003e\n  \u003cdd\u003eApproximately 17 × 14.4 inches (432 × 366 mm)\u003c\/dd\u003e\n  \u003cdt\u003eWeight\u003c\/dt\u003e\n  \u003cdd\u003eApproximately 1.72 kg (3.79 lb)\u003c\/dd\u003e\n  \u003cdt\u003eFitting Type\u003c\/dt\u003e\n  \u003cdd\u003eDrill and bolt\u003c\/dd\u003e\n  \u003cdt\u003eHydrofoil Profile\u003c\/dt\u003e\n  \u003cdd\u003eCurved profile designed to provide stern lift and help reduce porpoising\u003c\/dd\u003e\n\u003c\/dl\u003e\n\n\u003ch2\u003eWhat's in the Box\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e1 × Hydrofoil stabilizer\u003c\/li\u003e\n  \u003cli\u003e4 × Sets of stainless-steel screws, washers, and nuts\u003c\/li\u003e\n  \u003cli\u003e1 × 6.5 mm drill bit\u003c\/li\u003e\n  \u003cli\u003e1 × Installation instruction sheet\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n  \u003cli\u003eFor safety, disconnect the engine battery before beginning installation.\u003c\/li\u003e\n  \u003cli\u003eCenter the hydrofoil on the anti-cavitation plate or compatible drive mounting surface. Position it as far back as practical without interfering with propeller movement or steering components.\u003c\/li\u003e\n  \u003cli\u003eUse the hydrofoil mounting holes as a template and mark the four drilling points.\u003c\/li\u003e\n  \u003cli\u003eRemove the hydrofoil and carefully drill the marked holes with the included 6.5 mm drill bit, provided the plate thickness and material are suitable for drilling.\u003c\/li\u003e\n  \u003cli\u003ePlace the hydrofoil on the plate and align it with the drilled holes.\u003c\/li\u003e\n  \u003cli\u003eInsert the stainless-steel bolts from the top and secure them underneath with the washers and nuts.\u003c\/li\u003e\n  \u003cli\u003eTighten the fasteners evenly and securely. Do not overtighten, as this may damage the plate or the hydrofoil.\u003c\/li\u003e\n  \u003cli\u003eReconnect the battery and test the boat at low speed in a safe, open-water area. Check the installation again after the initial test run.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting and FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWill this hydrofoil fit my specific engine or drive?\u003c\/summary\u003e\n  \u003cp\u003eThis stabilizer is intended for many 40–300 HP outboard motors and stern drives, but fitment depends on the plate or drive geometry, available mounting area, clearance, and the exclusions listed above. Compare the dimensions and installation requirements with your equipment before ordering.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eDo I have to drill holes in the anti-cavitation plate?\u003c\/summary\u003e\n  \u003cp\u003eYes. This model uses a four-bolt installation and requires four holes to be drilled in a suitable mounting surface. If you are not certain that the plate can be drilled safely, consult a qualified marine technician.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow can a hydrofoil improve performance?\u003c\/summary\u003e\n  \u003cp\u003eThe hydrofoil adds hydrodynamic lift to the stern. Depending on the boat and setup, this may help the boat reach plane sooner, stay on plane at lower speeds, improve low-speed handling, and reduce bow bouncing or porpoising.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWill this reduce my boat's top speed?\u003c\/summary\u003e\n  \u003cp\u003eResults vary by boat, engine, propeller, loading, and installation. A hydrofoil may change handling and speed characteristics, and some setups may experience a small reduction in top speed because of added drag. Test the boat carefully after installation.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat is the benefit of reinforced PA66 nylon?\u003c\/summary\u003e\n  \u003cp\u003eReinforced PA66 nylon combines stiffness, impact resistance, and corrosion resistance. It is intended to provide a durable alternative to ordinary unreinforced plastic in a marine environment.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eIs this an OEM part?\u003c\/summary\u003e\n  \u003cp\u003eNo. This listing is for an aftermarket hydrofoil stabilizer. The FO2003 reference is provided as an aftermarket reference only and does not, by itself, establish OEM manufacture or universal interchangeability.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow should I confirm fitment before ordering?\u003c\/summary\u003e\n  \u003cp\u003eCheck the available mounting area, overall dimensions, anti-cavitation plate or drive shape, propeller and steering clearance, engine horsepower, and the model-specific exclusions. If any measurement or application detail differs, do not proceed without professional confirmation.\u003c\/p\u003e\n\u003c\/details\u003e\n\n\u003ch2\u003eSafety and Important Information\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eVerify the dimensions, mounting surface, clearances, and application notes against your equipment before purchase.\u003c\/li\u003e\n  \u003cli\u003eThis product requires drilling and bolting; professional marine installation is recommended when you are not experienced with structural or engine-related work.\u003c\/li\u003e\n  \u003cli\u003eInspect all fasteners and the hydrofoil after the first test run and periodically during use.\u003c\/li\u003e\n  \u003cli\u003eDo not operate the boat if the hydrofoil is loose, cracked, damaged, or interfering with the propeller, steering, or trim system.\u003c\/li\u003e\n  \u003cli\u003eThis is an aftermarket replacement product, not an OEM component.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePro-Grade Standards\u003c\/strong\u003e — We supply marine parts selected for dependable materials and real-world use.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer-Direct Value\u003c\/strong\u003e — We aim to provide practical replacement solutions with clear product information.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSupport-Focused Service\u003c\/strong\u003e — Confirm your application details before ordering and contact support if you need help reviewing product measurements or installation requirements.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50718235459899,"sku":"WV-JALU-N3EB","price":64.89,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/WV-JALU-N3EB.png?v=1762958052"}],"url":"https:\/\/seasierra.com\/collections\/4-stroke-50hp-outboard-marine-engine.oembed","provider":"SeaSierra","version":"1.0","type":"link"}