{"title":"UanofCn 4-Stroke 9.9HP Outboard Marine Engine Parts","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 is for UanofCn 4-Stroke 9.9HP outboard engines. It helps you find compatible parts and service information, including maintenance tips, common replacement parts, and troubleshooting guidance. You can also browse the main Mercury collection. Scroll to the bottom of this page to start browsing parts for this engine. On the collection page, use the Filter \u0026amp; Sort controls to narrow results by horsepower, year range, and part category.\u003c\/p\u003e\n  \u003cp\u003e\n    \u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-outboard-parts\" style=\"display:inline-block;padding:10px 14px;background:#0ea5e9;color:#fff;text-decoration:none;border-radius:6px\"\u003eBrowse All Mercury Parts\u003c\/a\u003e\n  \u003c\/p\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"identify-model\" style=\"max-width:980px;margin:0 auto 24px auto\"\u003e\n  \u003ch2\u003eHow to Identify Your 9.9HP Model\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eNameplate\/serial location: typically on the transom bracket or swivel bracket. Record the full model and serial number before ordering parts.\u003c\/li\u003e\n    \u003cli\u003eModel code and suffix: note shaft length (S=15, L=20), tiller vs. remote controls, and manual vs. electric start. These options affect certain parts (housings, harnesses, and controls).\u003c\/li\u003e\n    \u003cli\u003e4-stroke details: most 9.9HP 4-strokes in this class are twin-cylinder units. Earlier units are usually carbureted, while later versions may be EFI in some markets.\u003c\/li\u003e\n    \u003cli\u003ePlatform clues: cooling-system parts (like the impeller) are often shared across 615HP families; always confirm by serial number when in doubt.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"engine-overview\" style=\"max-width:980px;margin:0 auto 24px auto\"\u003e\n  \u003ch2\u003eEngine Overview\u003c\/h2\u003e\n  \u003ch3\u003e9.9HP 4-Stroke Small Twin\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 #f3f4f6\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eInline-2, 4-stroke, carbureted on earlier models; later variants may use electronic fuel injection. Air- or water-cooled oiling passages per 4-stroke architecture.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eGeneral 9.9HP 4-stroke outboards in the small twin family (standard and long shaft, tiller or remote, manual or electric start).\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eQuiet operation, good fuel economy, easy portability, and broad parts availability.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eMany cooling-system components are shared across 615HP families. Certain parts differ by serial range, shaft length, and starting\/controls. Verify by model \u0026amp; serial before purchase.\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 24px auto\"\u003e\n  \u003ch2\u003eRoutine Maintenance \u0026amp; Service Parts\u003c\/h2\u003e\n  \u003cp\u003eIntervals below are general guidelines for small 4-stroke outboards. Always follow your official service manual and adjust for heavy use, sandy\/silty water, or long storage periods.\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 #f3f4f6\"\u003eEngine oil \u0026amp; filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003e100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eWarm engine before draining; replace crush washer if equipped; use NMMA FC-W compliant oil.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\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 #f3f4f6\"\u003eGear oil (lower unit)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003e100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eChange more often if water intrusion is suspected; inspect magnetic drain plug for metal.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/lower-unit-seal-kits\"\u003eLower 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 #f3f4f6\"\u003eSpark plugs\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eInspect 100 hours; replace 200 hours or as needed\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eCheck gap and insulator color; replace if fouled or worn.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/spark-plug\"\u003eSpark Plug\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eFuel filter (inline)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003e100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eReplace sooner if storage or ethanol-related debris is present; use fresh stabilized fuel.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\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 #f3f4f6\"\u003eWater pump impeller \/ kit\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eEvery 2 seasons (or 200 hours)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eReplace more frequently in sandy\/silty water or if tell-tale flow is weak.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\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 #f3f4f6\"\u003eAnodes (corrosion protection)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eInspect every service; replace when 50% consumed\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eUse the correct alloy (zinc, aluminum, or magnesium) for your water type.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\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  \u003cp style=\"font-size:12px;color:#6b7280;margin-top:6px\"\u003e*Follow your engines service manual for exact intervals and procedures.\u003c\/p\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"common-parts\" style=\"max-width:980px;margin:0 auto 24px auto\"\u003e\n  \u003ch2\u003eFrequently Used Parts Categories\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eRoutine Service  \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 or \u003ca href=\"https:\/\/seasierra.com\/collections\/water-pump-impeller-rebuild-kits\"\u003eWater Pump Impeller Rebuild Kits\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eFuel System  \u003ca href=\"https:\/\/seasierra.com\/collections\/fuel-filters-1\"\u003eFuel Filters\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eIgnition \/ Electrical  \u003ca href=\"https:\/\/seasierra.com\/collections\/electrical-items\"\u003eElectrical Items\u003c\/a\u003e and \u003ca href=\"https:\/\/seasierra.com\/collections\/spark-plug\"\u003eSpark Plug\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCorrosion Protection  \u003ca href=\"https:\/\/seasierra.com\/collections\/anodes\"\u003eAnodes\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eGearcase \u0026amp; Propulsion  \u003ca href=\"https:\/\/seasierra.com\/collections\/lower-unit-seal-kits\"\u003eLower Unit Seal Kits\u003c\/a\u003e and \u003ca href=\"https:\/\/seasierra.com\/collections\/propellers\"\u003ePropellers\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eSafety \u0026amp; Protection  \u003ca href=\"https:\/\/seasierra.com\/collections\/propeller-guards\"\u003ePropeller Guards\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 24px 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 #f3f4f6\"\u003eWeak tell-tale stream or overheat alarm\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eInspect intake screen for blockage; verify water pump impeller condition; check thermostat operation.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\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 #f3f4f6\"\u003ePoor acceleration or power loss\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eReplace\/inspect fuel filter; check spark plugs; confirm prop pitch\/condition and for fishing line on the prop shaft.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eFuel filter, spark plugs, propeller\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eHard starting or rough idle (warm or cold)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eConfirm fresh, stabilized fuel; inspect\/replace plugs; check primer bulb and fuel lines for air leaks.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eSpark plugs, fuel filter, fuel hose\/primer bulb\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eGearcase noise or metal in gear oil\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eInspect gear oil level\/condition; pressure test for seal leaks; check for fishing line on prop shaft.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eLower unit seal kit, prop shaft seals, drain plug gaskets\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eExcessive smoke (4-stroke)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eVerify oil level (not overfilled); check for rich mixture or flooded carb; inspect air intake path.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6\"\u003eSpark plugs, air filter, carburetor components\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 24px auto\"\u003e\n  \u003ch2\u003eFAQs\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eAre parts interchangeable across different years or platforms?\u003c\/summary\u003e\n    \u003cp\u003eSome items are shared across the 615HP small-twin family, but many parts change by serial range, shaft length, and starting\/controls. Always confirm with your exact model and serial.\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 preventive measure, replace the impeller every 2 seasons (or about 200 hours). In sandy\/silty water or if the tell-tale weakens, service sooner.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow often should I change the gear oil?\u003c\/summary\u003e\n    \u003cp\u003eAt least every 100 hours or once per season. If you see milky oil (water intrusion) or metal on the magnet, service immediately and pressure-test the gearcase.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat information do you need to verify compatibility?\u003c\/summary\u003e\n    \u003cp\u003eProvide the full model and serial number, shaft length (S\/L), tiller or remote controls, and whether its manual or electric start. Photos of the nameplate help ensure a correct match.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"cta\" style=\"padding:16px;border:1px solid #e5e7eb;border-radius:8px;max-width:980px;margin:0 auto 20px auto\"\u003e\n  \u003cp\u003eReady to find what you need? Browse the main Mercury collection and narrow by horsepower, year, and model.\u003c\/p\u003e\n  \u003cp\u003e\n    \u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-outboard-parts\" style=\"display:inline-block;padding:10px 14px;background:#0ea5e9;color:#fff;text-decoration:none;border-radius:6px\"\u003eShop Mercury Outboard Parts\u003c\/a\u003e\n  \u003c\/p\u003e\n  \u003cp style=\"font-size:12px;color:#6b7280\"\u003eIf youre unsure about your model, send us a photo of the nameplate and the part you need and well help verify compatibility.\u003c\/p\u003e\n\u003c\/section\u003e","products":[{"product_id":"hydrofoil-stabilizer-fits-outboard-motors-5-150-hp-replaces-seasierra-fo2001-quickmarine-hs001","title":"Hydrofoil Stabilizer for Outboard Motors, 5–150 HP – Aftermarket Replacement for FO2001 and HS001","description":"\u003csection\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 { padding:10px 12px; border:1px solid #e5e7eb; text-align:left; vertical-align:top; }\n  table.ss-table th { white-space:nowrap; word-break:normal; letter-spacing:normal; font-weight:600; background:#f8fafc; }\n  @media (max-width:480px){ table.ss-table th, table.ss-table td { padding:8px 10px; font-size:14px; } }\n\u003c\/style\u003e\n\n\u003ch2\u003eProduct Details\u003c\/h2\u003e\n\u003cp\u003eThis \u003cstrong\u003eHydrofoil Stabilizer\u003c\/strong\u003e is a wing-shaped planing aid designed to mount on the anti-ventilation plate of compatible outboard motors and stern drives rated from 5 to 150 HP. It helps the boat plane faster, reduces bow rise, improves low-speed stability and handling, and may improve fuel efficiency depending on the boat, engine, load, trim and operating conditions. It is suitable for use with compatible 2-stroke and 4-stroke outboard applications.\u003c\/p\u003e\n\u003cp\u003eThis aftermarket hydrofoil is listed as a replacement reference for \u003cstrong\u003eFO2001\u003c\/strong\u003e and \u003cstrong\u003eHS001\u003c\/strong\u003e numbers used by various aftermarket sellers, including SeaSierra, QuickMarine, UanofCn, Xingrong and NorthBoat. These references are not OEM manufacturer part numbers.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eMounts to the anti-ventilation plate with the supplied bolt-on hardware.\u003c\/li\u003e\n  \u003cli\u003eMade from marine-grade, UV-resistant reinforced nylon PA66 plastic for use in freshwater and saltwater environments.\u003c\/li\u003e\n  \u003cli\u003eDorsal-fin-style design provides an enlarged wing surface for added stern lift and stability.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n\u003cp\u003eUse the following aftermarket references when comparing replacement products. Confirm the hydrofoil dimensions, mounting-hole pattern and included hardware before installation.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Aftermarket Part Number Matrix\"\u003e\n    \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eBrand or Seller Reference\u003c\/th\u003e\n\u003cth\u003ePart Number\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n\u003ctd\u003eSeaSierra\u003c\/td\u003e\n\u003ctd\u003eFO2001\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eQuickMarine\u003c\/td\u003e\n\u003ctd\u003eHS001\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eUanofCn\u003c\/td\u003e\n\u003ctd\u003eFO2001\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eXingrong\u003c\/td\u003e\n\u003ctd\u003eHS001\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eNorthBoat\u003c\/td\u003e\n\u003ctd\u003eHS001\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eEngine and Model Compatibility\u003c\/h2\u003e\n\u003cp\u003eThis is a general-fit aftermarket hydrofoil intended for compatible outboard motors and stern drives rated between 5 and 150 HP. Because anti-ventilation-plate dimensions and mounting arrangements vary, verify the available plate area, clearance around the propeller and the installation requirements for your specific engine before purchase.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Engine and Model Compatibility\"\u003e\n    \u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eBrand\u003c\/th\u003e\n\u003cth\u003eApplication\u003c\/th\u003e\n\u003cth\u003eRated HP\u003c\/th\u003e\n\u003cth\u003eStroke\u003c\/th\u003e\n\u003cth\u003eYears\u003c\/th\u003e\n\u003cth\u003eOEM Part No.\u003c\/th\u003e\n\u003cth\u003eNotes\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eCompatible outboards\u003c\/td\u003e\n\u003ctd\u003e5–150\u003c\/td\u003e\n\u003ctd\u003e2-Stroke and 4-Stroke\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eAftermarket application; verify plate dimensions and clearance.\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMercury\u003c\/td\u003e\n\u003ctd\u003eCompatible outboards\u003c\/td\u003e\n\u003ctd\u003e5–150\u003c\/td\u003e\n\u003ctd\u003e2-Stroke and 4-Stroke\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eAftermarket application; verify plate dimensions and clearance.\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eHonda\u003c\/td\u003e\n\u003ctd\u003eCompatible outboards\u003c\/td\u003e\n\u003ctd\u003e5–150\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eAftermarket application; verify plate dimensions and clearance.\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eSuzuki\u003c\/td\u003e\n\u003ctd\u003eCompatible outboards\u003c\/td\u003e\n\u003ctd\u003e5–150\u003c\/td\u003e\n\u003ctd\u003e2-Stroke and 4-Stroke\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eAftermarket application; verify plate dimensions and clearance.\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eTohatsu\u003c\/td\u003e\n\u003ctd\u003eCompatible outboards\u003c\/td\u003e\n\u003ctd\u003e5–150\u003c\/td\u003e\n\u003ctd\u003e2-Stroke and 4-Stroke\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eAftermarket application; verify plate dimensions and clearance.\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eJohnson\u003c\/td\u003e\n\u003ctd\u003eCompatible outboards\u003c\/td\u003e\n\u003ctd\u003e5–150\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eAftermarket application; verify plate dimensions and clearance.\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eEvinrude\u003c\/td\u003e\n\u003ctd\u003eCompatible outboards\u003c\/td\u003e\n\u003ctd\u003e5–150\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eAftermarket application; verify plate dimensions and clearance.\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003eCompatible stern drives\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eVerify anti-ventilation-plate suitability before installation.\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eOMC\u003c\/td\u003e\n\u003ctd\u003eCompatible stern drives\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eNot specified\u003c\/td\u003e\n\u003ctd\u003eVerify anti-ventilation-plate suitability before installation.\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 \/ planing aid\u003c\/dd\u003e\n  \u003cdt\u003eInstallation\u003c\/dt\u003e\n\u003cdd\u003eMounts to the anti-ventilation plate with supplied hardware\u003c\/dd\u003e\n  \u003cdt\u003eFuel Type\u003c\/dt\u003e\n\u003cdd\u003eNot applicable; external engine accessory\u003c\/dd\u003e\n  \u003cdt\u003eConnection\u003c\/dt\u003e\n\u003cdd\u003eBolt-on installation with supplied hardware\u003c\/dd\u003e\n  \u003cdt\u003eHousing Material\u003c\/dt\u003e\n\u003cdd\u003eMarine-grade, UV-resistant reinforced nylon PA66 plastic\u003c\/dd\u003e\n  \u003cdt\u003eHousing Color\u003c\/dt\u003e\n\u003cdd\u003eYellow, black, blue, gray or white; color availability may vary\u003c\/dd\u003e\n  \u003cdt\u003eDimensions\u003c\/dt\u003e\n\u003cdd\u003e10-1\/4 in × 8-1\/4 in (260.4 mm × 209.6 mm)\u003c\/dd\u003e\n  \u003cdt\u003eWeight\u003c\/dt\u003e\n\u003cdd\u003e2.41 lb (1.09 kg)\u003c\/dd\u003e\n  \u003cdt\u003eFitting Type\u003c\/dt\u003e\n\u003cdd\u003eGeneral fit for compatible outboard motors and stern drives\u003c\/dd\u003e\n  \u003cdt\u003eThread Size\u003c\/dt\u003e\n\u003cdd\u003eNot specified; stainless steel mounting hardware is supplied\u003c\/dd\u003e\n  \u003cdt\u003eDesign\u003c\/dt\u003e\n\u003cdd\u003eDorsal-fin style with enlarged wing surface\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 and nuts\u003c\/li\u003e\n  \u003cli\u003e1 × 6.5 mm drill bit\u003c\/li\u003e\n  \u003cli\u003e1 × Installation instructions\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n  \u003cli\u003eDisconnect the engine battery and make sure the engine is tilted up and secured safely.\u003c\/li\u003e\n  \u003cli\u003ePosition the hydrofoil on the anti-ventilation plate. Center it and confirm that it will not interfere with propeller movement or steering components.\u003c\/li\u003e\n  \u003cli\u003eMark the drilling locations through the hydrofoil's mounting holes.\u003c\/li\u003e\n  \u003cli\u003eRemove the hydrofoil and carefully drill the marked holes using the supplied 6.5 mm drill bit, if appropriate for the plate and installation.\u003c\/li\u003e\n  \u003cli\u003ePlace the hydrofoil back on the plate and align the holes.\u003c\/li\u003e\n  \u003cli\u003eInsert the stainless steel screws from the top and secure them with the nuts from below. Tighten firmly without over-torquing or deforming the plate.\u003c\/li\u003e\n  \u003cli\u003eCheck that all hardware is tight and that the hydrofoil is securely attached.\u003c\/li\u003e\n  \u003cli\u003eTest the boat at low speed before full-speed operation. Check handling, vibration, clearance and hardware tightness.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting and FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\u003csummary\u003eHow do I confirm that this hydrofoil fits my specific outboard motor?\u003c\/summary\u003e\u003cp\u003eCheck that your anti-ventilation plate is large enough for the 10-1\/4 in × 8-1\/4 in hydrofoil and that the installation area provides adequate propeller, steering and trim clearance. Horsepower range alone does not guarantee fitment. Compare the product dimensions and mounting arrangement with your engine before drilling.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat is the advantage of the dorsal-fin-style design?\u003c\/summary\u003e\u003cp\u003eThe fin and wing shape provide additional planing surface and stern lift. This can improve low-speed stability, reduce bow rise and help the boat reach a stable planing attitude more quickly. Results vary with hull design, engine setup, load and trim.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhy is my boat slower after installation?\u003c\/summary\u003e\u003cp\u003eA hydrofoil can increase drag in some installations. Recheck that the hydrofoil is centered, secure and correctly aligned with the anti-ventilation plate. Confirm that it does not contact or obstruct the propeller and that the engine trim is appropriate. If handling or vibration is abnormal, stop operating the boat and inspect the installation.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eCan I install it myself?\u003c\/summary\u003e\u003cp\u003eInstallation can be completed by a person with suitable mechanical skills and tools, but it requires drilling the anti-ventilation plate. If you are not confident about drilling, alignment, clearance or fastening, have the work completed or inspected by a qualified marine technician.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat are the signs that the hydrofoil needs replacement?\u003c\/summary\u003e\u003cp\u003eInspect it regularly for cracks, warping, impact damage, loose fasteners or abnormal vibration. Replace the hydrofoil if it is damaged or cannot be secured firmly. Inspect the mounting plate and hardware at the same time.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWill it prevent porpoising?\u003c\/summary\u003e\u003cp\u003eA hydrofoil may reduce porpoising by adding stern lift and helping the boat maintain a more consistent planing attitude, but it cannot guarantee elimination of porpoising. Correct weight distribution, engine trim and hull setup also affect the result.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eIs this an OEM part?\u003c\/summary\u003e\u003cp\u003eNo. This is an aftermarket replacement hydrofoil. FO2001 and HS001 are aftermarket reference numbers associated with comparable products; they should be used for comparison only, not as a claim of original-equipment manufacture.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat are the shipping and delivery details?\u003c\/summary\u003e\u003cp\u003eShipping methods, delivery estimates and cost are shown at checkout and may vary by destination and service selected.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat is the warranty and return policy?\u003c\/summary\u003e\u003cp\u003eWarranty coverage and return eligibility are governed by the seller's current policies. Contact customer support with your order details before returning or modifying a product if you experience a problem.\u003c\/p\u003e\u003c\/details\u003e\n\n\u003ch2\u003eSafety and Important Information\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eVerify the hydrofoil dimensions, plate size, mounting clearance and propeller clearance for your engine before drilling or purchasing.\u003c\/li\u003e\n  \u003cli\u003eThis is an aftermarket replacement, not an OEM component.\u003c\/li\u003e\n  \u003cli\u003eInspect all fasteners before each use, especially after the first water test and after any impact.\u003c\/li\u003e\n  \u003cli\u003eStop operation immediately if you notice vibration, looseness, cracking, steering changes or contact with the propeller.\u003c\/li\u003e\n  \u003cli\u003eProfessional installation is recommended when drilling or marine hardware installation is outside your experience.\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 practical fitment and real-world use.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGlobal Fulfillment\u003c\/strong\u003e — Available shipping options and delivery estimates are shown during checkout.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer-Direct Value\u003c\/strong\u003e — We aim to provide practical replacement parts at competitive prices.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50718256726331,"sku":"SS-19HS001-Y","price":26.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/SS-19HS001-Y.png?v=1762958184"}],"url":"https:\/\/seasierra.com\/collections\/uanofcn-4-stroke-9-9hp-outboard-marine-engine-parts.oembed","provider":"SeaSierra","version":"1.0","type":"link"}