{"product_id":"water-pump-impeller-kit-fits-yamaha-50-70-hp-replaces-6h3-w0078-00-6h3-w0078-02-00","title":"Water Pump Impeller Kit – Fits Yamaha 50-70 HP (Replaces 6H3-W0078-00, 6H3-W0078-02-00)","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\u003ch2\u003eProduct Details\u003c\/h2\u003e\n\u003cp\u003eThis \u003cstrong\u003eWater Pump Impeller Kit – Fits Yamaha 50 60 70 HP Outboards\u003c\/strong\u003e is designed for a wide range of Yamaha outboards, including 2-stroke 50–70 HP models (1984–2003) and 4-stroke 40–60 HP models (1999–2019). It provides all necessary components for a complete water pump service to maintain your engine’s cooling system.\u003c\/p\u003e\n\u003cp\u003eThis kit serves as a direct interchange for multiple OEM and aftermarket part numbers, including the Yamaha 6H3-W0078 series, Sierra 18-3464 series, and GLM 12057\/12283.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eInstalls in the lower unit gearcase to restore cooling system performance.\u003c\/li\u003e\n\u003cli\u003eImpeller is made from durable, high-performance CR Neoprene rubber for reliability.\u003c\/li\u003e\n\u003cli\u003eIncludes essential hardware like a Woodruff key, gaskets, and bolts for a complete installation.\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 Cross-Reference\"\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\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6H3-W0078-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6H3-W0078-02\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6H3-W0078-A0-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-3464\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-3465\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-3466\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eGLM\u003c\/td\u003e\n\u003ctd\u003e12057\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eGLM\u003c\/td\u003e\n\u003ctd\u003e12283\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\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Compatible Engine Models\"\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\u003e60\u003c\/td\u003e\n\u003ctd\u003e60 HP\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e2001–2003\u003c\/td\u003e\n\u003ctd\u003e6H3-W0078-02\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e60\u003c\/td\u003e\n\u003ctd\u003e60 HP\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e2004–2005\u003c\/td\u003e\n\u003ctd\u003e692-W0078-02\u003c\/td\u003e\n\u003ctd\u003eSuperseded part\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eC60\u003c\/td\u003e\n\u003ctd\u003e60 HP\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1996–2001\u003c\/td\u003e\n\u003ctd\u003e6H3-W0078-02\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eE60\u003c\/td\u003e\n\u003ctd\u003e60 HP\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1995–1996\u003c\/td\u003e\n\u003ctd\u003e6H3-W0078-02\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eP60\u003c\/td\u003e\n\u003ctd\u003e60 HP\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1991\u003c\/td\u003e\n\u003ctd\u003e6H3-W0078-02\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eP60\u003c\/td\u003e\n\u003ctd\u003e60 HP\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1992–1999\u003c\/td\u003e\n\u003ctd\u003e6H3-W0078-02\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e70\u003c\/td\u003e\n\u003ctd\u003e70 HP\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1984–2003\u003c\/td\u003e\n\u003ctd\u003e6H3-W0078-02\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eC70\u003c\/td\u003e\n\u003ctd\u003e70 HP\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e2000–2001\u003c\/td\u003e\n\u003ctd\u003e6H3-W0078-02\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eF40\u003c\/td\u003e\n\u003ctd\u003e40 HP\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1999\u003c\/td\u003e\n\u003ctd\u003e6H3-W0078-02\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eF50\u003c\/td\u003e\n\u003ctd\u003e50 HP\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1997\u003c\/td\u003e\n\u003ctd\u003e6H3-W0078-02\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eFT50\u003c\/td\u003e\n\u003ctd\u003e50 HP\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1997–2017\u003c\/td\u003e\n\u003ctd\u003e6H3-W0078-02\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eFT60\u003c\/td\u003e\n\u003ctd\u003e60 HP\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e2002–2017\u003c\/td\u003e\n\u003ctd\u003e6H3-W0078-02\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eT50\u003c\/td\u003e\n\u003ctd\u003e50 HP\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1996\u003c\/td\u003e\n\u003ctd\u003e6H3-W0078-02\u003c\/td\u003e\n\u003ctd\u003e\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\u003eWater Pump Impeller Kit\u003c\/dd\u003e\n  \u003cdt\u003eInstallation\u003c\/dt\u003e\n\u003cdd\u003eLower Unit Gearcase\u003c\/dd\u003e\n  \u003cdt\u003eHousing Material\u003c\/dt\u003e\n\u003cdd\u003eNylon PA66 Plastic (housing), Stainless Steel (plate\/cup)\u003c\/dd\u003e\n  \u003cdt\u003eHousing Color\u003c\/dt\u003e\n\u003cdd\u003eWhite\/Beige\u003c\/dd\u003e\n  \u003cdt\u003eImpeller Material\u003c\/dt\u003e\n\u003cdd\u003eCR Neoprene Rubber\u003c\/dd\u003e\n  \u003cdt\u003eWeight\u003c\/dt\u003e\n\u003cdd\u003e0.24 kg (8.7 oz)\u003c\/dd\u003e\n  \u003cdt\u003eWarranty\u003c\/dt\u003e\n\u003cdd\u003eManufacturer dependent, typically 1 year\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 Water Pump Impeller (6H3-44352-00-00)\u003c\/li\u003e\n  \u003cli\u003e1 x Woodruff Key (90280-03M03-00)\u003c\/li\u003e\n  \u003cli\u003e1 x Cartridge Insert (663-44322-00-00)\u003c\/li\u003e\n  \u003cli\u003e1 x Cartridge Outer Plate (6H3-44323-00-00)\u003c\/li\u003e\n  \u003cli\u003e1 x Cartridge Gasket (6H3-44324-A0-00)\u003c\/li\u003e\n  \u003cli\u003e1 x Water Pump Gasket (6H3-44315-A0-00)\u003c\/li\u003e\n  \u003cli\u003e1 x Water Pump Gasket (688-44316-A0-00)\u003c\/li\u003e\n  \u003cli\u003e1 x O-Ring (93210-46044-00)\u003c\/li\u003e\n  \u003cli\u003e2 x Bolt With Washer (90119-08M14-00)\u003c\/li\u003e\n  \u003cli\u003e2 x Bolt With Washer (90119-08M33-00)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n  \u003cli\u003eDisconnect the battery and shift the outboard into the neutral position.\u003c\/li\u003e\n  \u003cli\u003eCarefully remove the bolts securing the lower unit (gearcase) and detach it from the upper housing.\u003c\/li\u003e\n  \u003cli\u003eUnscrew the bolts on the water pump housing and remove the old housing, impeller, and gaskets.\u003c\/li\u003e\n  \u003cli\u003eThoroughly clean all mating surfaces, removing any old gasket material or corrosion.\u003c\/li\u003e\n  \u003cli\u003eInstall the new Woodruff key on the driveshaft and slide the new impeller on, turning it in the direction of engine rotation.\u003c\/li\u003e\n  \u003cli\u003ePlace the new gaskets, insert cartridge, and outer plate according to the service manual diagram.\u003c\/li\u003e\n  \u003cli\u003eSecure the new water pump housing with the provided bolts, tightening them to the manufacturer's specified torque.\u003c\/li\u003e\n  \u003cli\u003eCarefully guide the driveshaft and water tube while reinstalling the lower unit, ensuring everything aligns correctly.\u003c\/li\u003e\n  \u003cli\u003eReinstall and tighten the lower unit mounting bolts.\u003c\/li\u003e\n  \u003cli\u003eReconnect the battery, start the engine in water, and confirm a strong, steady stream from the cooling system's tell-tale port.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow do I know if this kit fits my Yamaha outboard?\u003c\/summary\u003e\n  \u003cp\u003eTo ensure compatibility, check your engine’s model, horsepower, and year against the detailed \"Engine \u0026amp; Model Compatibility\" table. This kit is specifically for Yamaha 2-stroke 50–70 HP (1984–2003) and 4-stroke 40–60 HP (1999–2019) models listed. Cross-referencing your engine's OEM part number is the best way to confirm fitment.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat are the signs of a failed water pump impeller?\u003c\/summary\u003e\n  \u003cp\u003eCommon signs include the engine overheating at idle or low speeds, a weak or non-existent water stream from the \"tell-tale\" outlet port, and a melted water pump housing. During a physical inspection, a worn impeller may have brittle, cracked, or broken vanes.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow often should I replace my water pump impeller?\u003c\/summary\u003e\n  \u003cp\u003eAs a best practice, we recommend inspecting the impeller annually and replacing it every 1-2 years or every 100-200 hours of use. Replacement intervals should be shorter for boats operated in saltwater or sandy\/silty conditions.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eOEM vs. Aftermarket?\u003c\/summary\u003e\n  \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\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eShipping speed \u0026amp; cost?\u003c\/summary\u003e\n  \u003cp\u003eWe ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWarranty \u0026amp; returns?\u003c\/summary\u003e\n  \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\n\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":50723973071163,"sku":"YY-20KY003","price":31.89,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/YY-20KY003.png?v=1763038890","url":"https:\/\/seasierra.com\/products\/water-pump-impeller-kit-fits-yamaha-50-70-hp-replaces-6h3-w0078-00-6h3-w0078-02-00","provider":"SeaSierra","version":"1.0","type":"link"}