{"title":"Sea Sierra 25HP 4-Stroke Outboard Marine Engine Parts","description":"\u003csection id=\"hero\" style=\"padding:16px 0;\"\u003e\n  \u003cp\u003eThis page is for Tohatsu 4‑Stroke 25HP 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 Tohatsu collection, then 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  \u003ca href=\"https:\/\/seasierra.com\/collections\/tohatsu-outboard-parts\" style=\"display:inline-block;padding:10px 16px;background:#0a6efd;color:#fff;text-decoration:none;border-radius:6px;\"\u003eBrowse All Tohatsu 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 25HP Model\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eLocate the nameplate\/serial tag on the transom bracket or swivel bracket; it lists model code and serial number.\u003c\/li\u003e\n    \u003cli\u003eRead the model code and suffix: shaft length (S\/L\/XL), control type (tiller vs. remote), and features (EFI vs. carbureted) are often encoded.\u003c\/li\u003e\n    \u003cli\u003eFor 4‑stroke variants, later engines are typically EFI while earlier units may be carbureted—note this when selecting fuel and ignition parts.\u003c\/li\u003e\n    \u003cli\u003eRecord the full model code and serial number before ordering; many wear items are shared with related 30HP variants but can change at serial breaks.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"engine-overview\" style=\"padding:16px 0;\"\u003e\n  \u003ch2\u003ePlatform Overview\u003c\/h2\u003e\n  \u003ch3\u003e25HP 4‑Stroke Inline‑3 Class\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 #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 3‑cylinder, 4‑stroke; EFI on many later models, earlier versions may be carbureted.\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;\"\u003eTohatsu 25HP 4‑stroke family (e.g., MFS25 EFI and related carbureted variants; some components shared with 30HP sisters—confirm by serial).\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, good fuel economy, strong low‑to‑mid torque, and clean emissions.\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;\"\u003eCooling, fuel, and ignition items are routine service parts. Always verify model code and serial number for part compatibility.\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\u003eIntervals below are general guidelines for typical use. Always follow the official service manual for your exact model, year, and operating conditions.\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 #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 + filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eFirst 20 hours, then every 100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eUse NMMA FC‑W oil and the specified filter; warm engine before draining.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\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 #eee;\"\u003eGear oil (lower unit)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eEvery 100 hours or annually; inspect after any impact\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eCheck for water intrusion (milky oil) and metal on the magnet.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/service-maintenance-kits\"\u003eService \u0026amp; Maintenance 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 hours; replace 200–300 hours or as needed\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eUse correct heat range and gap; replace sooner if fouled or corroded.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\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 #eee;\"\u003eFuel filter \/ water‑separating filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eInspect every 50–100 hours; replace annually or with contamination\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eCritical for EFI reliability; drain\/replace if water or debris is present.\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 seasons (freshwater); annually for heavy use or salt water\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eReplace sooner if telltale weakens, overheating occurs, or sand ingestion.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/water-pump-impeller-rebuild-kits\"\u003eWater Pump Impeller Rebuild 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 hours; replace when ~50% consumed\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eUse zinc (salt), aluminum (brackish\/salt), or magnesium (fresh only) per environment.\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    \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\/water-pump-impeller-rebuild-kits\"\u003eWater Pump \u0026amp; Impellers\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 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\u003ePropulsion – \u003ca href=\"https:\/\/seasierra.com\/collections\/propellers\"\u003ePropellers\u003c\/a\u003e and \u003ca href=\"https:\/\/seasierra.com\/collections\/outboard-hydrofoil-stabilizers\"\u003eHydrofoil Stabilizers\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eGearcase Seals – \u003ca href=\"https:\/\/seasierra.com\/collections\/tohatsu-lower-unit-seal-kits\"\u003eTohatsu Lower Unit Seal Kits\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%;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 telltale \/ overheat alarm\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eInspect intake screens for debris; verify impeller and thermostat operation.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eWater pump kit, thermostat, anodes\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 prop for damage\/cavitation; inspect fuel filter and primer bulb; verify spark plugs.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003ePropeller, fuel filter, fuel pump, spark plugs\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eHard starting \/ rough idle (EFI)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eDrain stale fuel; check for water in fuel; inspect injector and ignition connections.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eFuel filter, injectors, spark plugs, electrical items\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eGearcase noise or metal in gear oil\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eVerify oil level\/condition; check for water intrusion; inspect prop shaft for fishing line.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eLower unit seal kit, bearings, propeller\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eBattery not charging\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eTest battery and connections; check rectifier\/regulator output and grounds.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eRectifier\/regulator, electrical items\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 wear items are shared across adjacent horsepower models, but changes occur by year and at serial number breaks. Always verify using the full model code and serial number.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhen should the water pump impeller be replaced?\u003c\/summary\u003e\n    \u003cp\u003eInspect annually and replace every 1–2 seasons depending on use and water quality. Heavy use, sand, or saltwater operation justify annual replacement or sooner if the telltale weakens or overheating occurs.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow often should gear oil be changed?\u003c\/summary\u003e\n    \u003cp\u003eEvery 100 hours or annually, and immediately after any hard impact. Replace sooner if the oil appears milky (water contamination) or contains excessive metal shavings.\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 model code, serial number, shaft length, control type (tiller or remote), and whether the engine is EFI or carbureted. Photos of the nameplate and the part needing replacement are very helpful.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"cta\" style=\"padding:16px 0;\"\u003e\n  \u003cp\u003eReady to find the right components? Browse the main Tohatsu collection by horsepower, year, and model to pinpoint compatible parts.\u003c\/p\u003e\n  \u003ca href=\"https:\/\/seasierra.com\/collections\/tohatsu-outboard-parts\" style=\"display:inline-block;padding:10px 16px;background:#0a6efd;color:#fff;text-decoration:none;border-radius:6px;\"\u003eShop Tohatsu Parts\u003c\/a\u003e\n  \u003cp style=\"margin-top:8px;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":"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\/sea-sierra-25hp-4-stroke-outboard-marine-engine-parts.oembed","provider":"SeaSierra","version":"1.0","type":"link"}