{"title":"Sea Sierra 9.9HP 4-Stroke Outboard Marine Engine Parts","description":"\u003csection id=\"hero\" style=\"padding:16px 0;\"\u003e\n  \u003cp style=\"max-width:900px;\"\u003e\n    This page is dedicated to Honda 4‑Stroke 9.9HP outboard engines. Use it to find compatible parts and practical service information, including maintenance tips, common replacement items, and troubleshooting guidance. You can also browse our main Honda collection. Scroll to the bottom of the page to start browsing parts for this engine, and remember you can use the Filter \u0026amp; Sort controls on the collection page to narrow results by horsepower, year range, and part category.\n  \u003c\/p\u003e\n  \u003ca href=\"https:\/\/seasierra.com\/collections\/honda-outboard-parts\" style=\"display:inline-block;padding:10px 16px;background:#0073e6;color:#fff;text-decoration:none;border-radius:6px;\"\u003eBrowse All Honda Parts\u003c\/a\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"identify-model\" style=\"padding:16px 0;\"\u003e\n  \u003ch2\u003eHow to Identify Your 9.9HP Model\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eLocate the engine nameplate\/serial label on the transom or swivel bracket (commonly starboard side on Honda outboards).\u003c\/li\u003e\n    \u003cli\u003eRead the full model code and suffix (e.g., BF9.9D or BFP9.9D) including shaft length (S\/L\/X), control type (tiller or remote), and starting method (recoil or electric).\u003c\/li\u003e\n    \u003cli\u003eDistinguish platforms: Standard BF9.9D vs Power Thrust BFP9.9D (larger‑diameter prop and different gear ratio on Power Thrust models).\u003c\/li\u003e\n    \u003cli\u003eFor 4‑stroke models, note OHC inline‑2 configuration and carburetion; some service parts overlap with BF8D families—verify by model code and serial number.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"engine-overview\" style=\"padding:16px 0;\"\u003e\n  \u003ch2\u003eEngine\/Platform Overview\u003c\/h2\u003e\n\n  \u003ch3\u003eStandard BF9.9D\u003c\/h3\u003e\n  \u003ctable style=\"width:100%;max-width:1000px;border-collapse:collapse;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px;\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;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 #eee;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eInline‑2 OHC, 4‑stroke, carbureted, water‑cooled (small displacement twin)\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eBF9.9D in S\/L\/X shaft lengths; tiller (H) and remote (R) variants; recoil or electric start\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eQuiet operation, strong fuel economy, straightforward maintenance, widely available service parts\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eMany routine items interchange with BF8D; verify propeller, anodes, and gearcase seals by model code and shaft length.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\n  \u003ch3\u003ePower Thrust BFP9.9D\u003c\/h3\u003e\n  \u003ctable style=\"width:100%;max-width:1000px;border-collapse:collapse;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px;\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;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 #eee;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eSame base inline‑2 OHC engine with high‑thrust gearcase and larger‑diameter prop options\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eBFP9.9D in S\/L\/X; tiller or remote control configurations\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eImproved low‑speed thrust and control for heavier hulls, dinghies, sailboats, and trolling applications\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003ePropellers, gear ratios, and some anodes differ from standard BF9.9D—confirm by full model code and serial number before ordering.\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=\"padding:16px 0;\"\u003e\n  \u003ch2\u003eRoutine Maintenance \u0026amp; Service Parts\u003c\/h2\u003e\n  \u003cp style=\"max-width:900px;\"\u003eIntervals below are general guidelines—always follow your official Honda service manual and adjust for usage, environment, and storage conditions.\u003c\/p\u003e\n  \u003ctable style=\"width:100%;max-width:1000px;border-collapse:collapse;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px;\"\u003eItem\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px;\"\u003eInterval*\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px;\"\u003eRemarks\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;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 #eee;\"\u003eEngine oil \u0026amp; filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eFirst 20 hrs, then every 100 hrs or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eUse marine‑grade 4‑stroke oil of the specified viscosity; replace filter at each oil change.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/oil-filters\"\u003eShop Oil Filters\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eGear oil (lower unit)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eEvery 100 hrs or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eInspect magnetic drain plug and replace drain\/vent seals if damaged; check for water contamination.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/honda-lower-unit-seal-kits\"\u003eHonda 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 #eee;\"\u003eSpark plugs\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eInspect every 100 hrs; replace as needed\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eCheck gap and condition; replace if fouled, worn, or corroded.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/spark-plug\"\u003eShop Spark Plugs\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eInline fuel filter \/ water separator\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eInspect every 100 hrs; replace annually or if contaminated\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eUse fresh fuel; keep primer bulb and tank clean; look for water or sediment.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\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 #eee;\"\u003eWater pump impeller \/ kit\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eEvery 2–3 seasons (sooner in sandy\/silty use)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eWeak tell‑tale or overheat alarms often indicate a worn impeller; consider a full kit during service.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/honda-water-pump-repair-kits\"\u003eHonda 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 #eee;\"\u003eAnodes (sacrificial)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eInspect every 50–100 hrs; replace when ~50% consumed\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eChoose alloy for your water (zinc\/aluminum\/magnesium); never paint anodes.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/anodes\"\u003eAnodes\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003ePropeller \u0026amp; hardware\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eInspect frequently\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eLook for dings, bent blades, or fishing line on the shaft; replace cotter pin when removed.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/propellers\"\u003ePropellers\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=\"padding:16px 0;\"\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\/honda-water-pump-repair-kits\"\u003eHonda Water Pump Repair Kits\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eLower Unit \u0026amp; Seals — \u003ca href=\"https:\/\/seasierra.com\/collections\/honda-lower-unit-seal-kits\"\u003eHonda Lower Unit Seal 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\/spark-plug\"\u003eSpark Plugs\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\u003ePerformance \u0026amp; Handling — \u003ca href=\"https:\/\/seasierra.com\/collections\/outboard-hydrofoil-stabilizers\"\u003eOutboard Hydrofoil Stabilizers\u003c\/a\u003e and \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=\"padding:16px 0;\"\u003e\n  \u003ch2\u003eCommon Symptoms \u0026amp; Quick Checks\u003c\/h2\u003e\n  \u003ctable style=\"width:100%;max-width:1000px;border-collapse:collapse;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px;\"\u003eSymptom\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;padding:8px;\"\u003eCheck First\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;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 #eee;\"\u003eWeak tell‑tale stream or overheat alarm\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eInspect intake screens, confirm good fuel supply\/idle speed, and consider impeller age.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eWater pump kit, thermostat, intake screen, anodes\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eHard starting or rough idle\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eVerify fresh fuel, open tank vent, prime bulb, check plugs and idle mixture\/setting.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eSpark plugs, inline fuel filter, primer bulb, fuel pump, carburetor components\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003ePoor acceleration or power loss\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eCheck for prop damage or wrong pitch, fuel restriction, and throttle\/shift cable operation.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003ePropeller, spark plugs, fuel filter, fuel pump\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eGearcase noise or milky gear oil\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eLook for fishing line on prop shaft, replace gear oil, and inspect drain\/vent seals for leaks.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eLower unit seal kit, drain\/vent plug gaskets, propeller hardware\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eNo crank \/ no start (electric)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eConfirm lanyard clip, neutral position, battery charge and connections, and main fuses.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eIgnition switch, starter motor, rectifier\/regulator, spark plugs\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=\"padding:16px 0;\"\u003e\n  \u003ch2\u003eFAQs\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eAre parts interchangeable between different years or platforms?\u003c\/summary\u003e\n    \u003cp\u003eMany routine service items (filters, spark plugs, impeller kits, anodes) are shared across BF8D\/BF9.9D families. Power Thrust (BFP) variants often use different props, gear ratios, and some anodes—verify by full model code, shaft length, and serial number before ordering.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhen should the impeller be replaced?\u003c\/summary\u003e\n    \u003cp\u003eAs a rule of thumb, replace every 2–3 seasons under normal use. In sandy, weedy, or silty water—or if the tell‑tale weakens—service sooner and consider a full water pump kit.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow often should the lower unit gear oil be changed?\u003c\/summary\u003e\n    \u003cp\u003eChange at least annually or every 100 hours. Replace immediately if you see water contamination (milky oil) or after a fishing‑line incident on the prop shaft.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat information do you need to confirm part compatibility?\u003c\/summary\u003e\n    \u003cp\u003ePlease provide the exact model code (e.g., BF9.9D or BFP9.9D), full serial number, shaft length (S\/L\/X), control type (tiller or remote), and whether it has electric start. Clear photos of the nameplate and the existing part are also helpful.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"cta\" style=\"padding:16px 0;\"\u003e\n  \u003cp style=\"max-width:900px;\"\u003eReady to find parts by horsepower, year, and model? Browse our main Honda Outboard collection to dial in exactly what you need.\u003c\/p\u003e\n  \u003ca href=\"https:\/\/seasierra.com\/collections\/honda-outboard-parts\" style=\"display:inline-block;padding:10px 16px;background:#0073e6;color:#fff;text-decoration:none;border-radius:6px;\"\u003eShop Honda Outboard Parts\u003c\/a\u003e\n  \u003cp style=\"margin-top:8px;color:#555;\"\u003eIf you’re unsure about your model, send us a clear photo of the nameplate and the part you need—we’ll help verify compatibility before you order.\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 – Fits Outboard Motors 5-150 HP (Replaces SeaSierra FO2001, QuickMarine HS001)","description":"\u003csection\u003e\n\u003c!-- 🔧 Table Styles (include only once per page) --\u003e\n\u003cstyle\u003e\n  \/* Outer container allows horizontal scrolling (with iOS momentum) *\/\n  .ss-table-wrap { overflow-x:auto; -webkit-overflow-scrolling:touch; }\n\n  \/* Base table styles *\/\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\n  \/* Key: prevent wrapping, word breaks, and vertical text in headers *\/\n  table.ss-table th {\n    white-space:nowrap;       \/* Do not wrap *\/\n    word-break:normal;        \/* Don’t break words *\/\n    letter-spacing:normal;    \/* Prevent theme styles from stretching letters *\/\n    font-weight:600;\n    background:#f8fafc;\n  }\n\n  \/* Small screen optimization *\/\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 \u003cstrong\u003eHydrofoil Stabilizer\u003c\/strong\u003e is a wing-shaped planing aid designed to mount on the anti-ventilation plate of most outboard motors and stern drives from 5 to 150 HP. It improves boat handling, helps the vessel plane faster, reduces bow rise, and enhances overall fuel efficiency. It is compatible with both 2-stroke and 4-stroke engines.\u003c\/p\u003e\n\u003cp\u003eThis unit serves as a direct aftermarket replacement for several part numbers, including SeaSierra FO2001, QuickMarine HS001, UanofCn FO2001, Xingrong HS001, and NorthBoat HS001.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eMounts directly to the anti-ventilation plate with the included stainless steel bolt-on hardware.\u003c\/li\u003e\n  \u003cli\u003eConstructed from marine-grade, UV-resistant Reinforced Nylon PA66 plastic for durability in harsh saltwater and freshwater environments.\u003c\/li\u003e\n  \u003cli\u003eFeatures a dorsal fin style design for improved stability and enhanced wing surface area.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n\u003cp\u003eUse this matrix to confirm equivalent references across OEM and aftermarket.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Part Number Matrix\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eBrand\u003c\/th\u003e\n        \u003cth\u003ePart Number\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \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 \u0026amp; Model Compatibility\u003c\/h2\u003e\n\u003cp\u003eConfirm your engine model\/year in the table below.\u003c\/p\u003e\n\u003cp\u003eThis universal-fit hydrofoil is designed for most outboard motors and stern drives rated between 5 and 150 HP. The dorsal fin design ensures broad compatibility across many popular brands, including both 2-stroke and 4-stroke models.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Engine \u0026amp; Model Compatibility\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eBrand\u003c\/th\u003e\n        \u003cth\u003eModel\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\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eOutboards\u003c\/td\u003e\n        \u003ctd\u003e5-150\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke \u0026amp; 4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003eAftermarket part\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\u003c\/td\u003e\n        \u003ctd\u003eOutboards\u003c\/td\u003e\n        \u003ctd\u003e5-150\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke \u0026amp; 4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003eAftermarket part\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eHonda\u003c\/td\u003e\n        \u003ctd\u003eOutboards\u003c\/td\u003e\n        \u003ctd\u003e5-150\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003eAftermarket part\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eSuzuki\u003c\/td\u003e\n        \u003ctd\u003eOutboards\u003c\/td\u003e\n        \u003ctd\u003e5-150\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke \u0026amp; 4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003eAftermarket part\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eTohatsu\u003c\/td\u003e\n        \u003ctd\u003eOutboards\u003c\/td\u003e\n        \u003ctd\u003e5-150\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke \u0026amp; 4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003eAftermarket part\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eJohnson\u003c\/td\u003e\n        \u003ctd\u003eOutboards\u003c\/td\u003e\n        \u003ctd\u003e5-150\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003eAftermarket part\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eEvinrude\u003c\/td\u003e\n        \u003ctd\u003eOutboards\u003c\/td\u003e\n        \u003ctd\u003e5-150\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003eAftermarket part\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercruiser\u003c\/td\u003e\n        \u003ctd\u003eStern Drives\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003eAftermarket part\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eOMC\u003c\/td\u003e\n        \u003ctd\u003eStern Drives\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003eAftermarket part\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eTechnical Specs\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 anti-ventilation plate with included hardware\u003c\/dd\u003e\n  \u003cdt\u003eFuel Type\u003c\/dt\u003e\n\u003cdd\u003eN\/A (External component)\u003c\/dd\u003e\n  \u003cdt\u003eConnection\u003c\/dt\u003e\n\u003cdd\u003eBolt-on 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 variants available)\u003c\/dd\u003e\n  \u003cdt\u003eDimensions\u003c\/dt\u003e\n\u003cdd\u003e10-1\/4\" × 8-1\/4\" (260.4 mm × 209.6 mm)\u003c\/dd\u003e\n  \u003cdt\u003eWeight\u003c\/dt\u003e\n\u003cdd\u003e2.41 pounds (1.09 kg)\u003c\/dd\u003e\n  \u003cdt\u003eFitting Type\u003c\/dt\u003e\n\u003cdd\u003eUniversal fit for outboard motors and stern drives\u003c\/dd\u003e\n  \u003cdt\u003eThread Size\u003c\/dt\u003e\n\u003cdd\u003eIncludes stainless steel mounting hardware\u003c\/dd\u003e\n  \u003cdt\u003eOther Technical Attributes\u003c\/dt\u003e\n\u003cdd\u003eDorsal fin style design with enhanced wing surface area\u003c\/dd\u003e\n\u003c\/dl\u003e\n\n\u003ch2\u003eWhat’s in the Box\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e1 x Hydrofoil Stabilizer\u003c\/li\u003e\n  \u003cli\u003e\u003cspan style=\"color:#d0021b;\"\u003e4 x Sets of Stainless Steel Screws and Nuts\u003c\/span\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003cspan style=\"color:#d0021b;\"\u003e1 x 6.5mm Drill Bit\u003c\/span\u003e\u003c\/li\u003e\n  \u003cli\u003e1 x 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's battery and ensure the engine is tilted up securely.\u003c\/li\u003e\n  \u003cli\u003ePosition the hydrofoil on the anti-ventilation (cavitation) plate. Center it and ensure it does not interfere with the propeller's movement.\u003c\/li\u003e\n  \u003cli\u003eUse a marker to mark the drilling locations on the plate through the mounting holes in the hydrofoil.\u003c\/li\u003e\n  \u003cli\u003eRemove the hydrofoil and carefully drill the marked holes using the supplied 6.5mm drill bit.\u003c\/li\u003e\n  \u003cli\u003ePlace the hydrofoil back onto the plate, aligning the holes.\u003c\/li\u003e\n  \u003cli\u003eInsert the stainless steel screws from the top and secure them with the nuts from the bottom. Tighten securely, but do not over-torque to avoid damaging the plate.\u003c\/li\u003e\n  \u003cli\u003eDouble-check that all hardware is tight and the hydrofoil is firmly attached.\u003c\/li\u003e\n  \u003cli\u003eBefore full-speed operation, conduct a water test at low speeds to check for any changes in handling or performance.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\u003csummary\u003eHow do I confirm this hydrofoil will fit my specific outboard motor?\u003c\/summary\u003e\u003cp\u003eThis hydrofoil offers a universal fit for most outboard and stern drive motors from 5-150 HP. The key is to check your anti-ventilation plate's size. The hydrofoil's dimensions are 10-1\/4\" × 8-1\/4\", so your plate should be large enough to accommodate it without interfering with the propeller.\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 dorsal fin design provides added stability at both high and low speeds. It helps control ventilation (air being drawn into the propeller) and reduces prop blow-out during sharp turns, leading to more precise handling.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eI installed the hydrofoil, but my boat is now slower. What's wrong?\u003c\/summary\u003e\u003cp\u003eWhile hydrofoils improve planing and stability, they can slightly reduce top-end speed due to increased drag. If the speed loss is significant, re-check the installation angle and position. Ensure the hydrofoil is parallel to the bottom of the boat. Incorrect mounting can create excessive drag.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eCan I install this myself, or do I need a marine mechanic?\u003c\/summary\u003e\u003cp\u003eThe installation is straightforward for those with basic mechanical skills and tools. The kit includes all necessary hardware and a drill bit. However, if you are not comfortable drilling into your engine's anti-ventilation plate, professional installation is recommended to ensure safety and proper alignment.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat are the signs that the hydrofoil needs replacement?\u003c\/summary\u003e\u003cp\u003eInspect the hydrofoil regularly for signs of stress cracks, warping, or physical damage, especially after impacts. Also, check that the mounting hardware remains tight. If the unit is damaged or cannot be secured firmly, it should be replaced.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWill this prevent porpoising?\u003c\/summary\u003e\u003cp\u003eA hydrofoil can significantly reduce or eliminate porpoising (the rhythmic bouncing of the bow) by providing stern lift and keeping the bow down. It helps maintain a more consistent and stable planing attitude.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eOEM vs. Aftermarket?\u003c\/summary\u003e\u003cp\u003eThis listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eShipping speed \u0026amp; cost\u003c\/summary\u003e\u003cp\u003eWe ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWarranty \u0026amp; returns\u003c\/summary\u003e\u003cp\u003eCovered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused \u0026amp; in original condition). See our policy page or reach out for instructions.\u003c\/p\u003e\u003c\/details\u003e\n\n\u003ch2\u003eSafety \u0026amp; Important Info\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eVerify images\/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.\u003c\/li\u003e\n  \u003cli\u003eThis is an aftermarket replacement, not an OEM component.\u003c\/li\u003e\n  \u003cli\u003eProfessional installation is recommended for safety and performance.\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 engineered to OEM-level tolerances and tested for real-world conditions.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFast Global Fulfillment\u003c\/strong\u003e — Free standard delivery to most regions in 5–15 days.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer-Direct Value\u003c\/strong\u003e — Fair pricing without compromising on materials or QC.\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\/sea-sierra-9-9hp-4-stroke-outboard-marine-engine-parts.oembed","provider":"SeaSierra","version":"1.0","type":"link"}