{"product_id":"water-pump-impeller-kit-fits-yamaha-25-50-hp-replaces-6h4-44352-6h4-w0078-00","title":"Water Pump Impeller Kit – Fits Yamaha 25-50 HP (Replaces 6H4-44352, 6H4-W0078-00)","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\n\u003ch2\u003eProduct Details\u003c\/h2\u003e\n\u003cp\u003eThis aftermarket \u003cstrong\u003eWater Pump Impeller Kit\u003c\/strong\u003e is a direct-fit replacement for a wide range of Yamaha outboard motors. It is designed for various 2-stroke models including 25 HP (1996–2002), 30 HP (1987–2001), 40 HP (1984–1994), and 50 HP (1984–1994), as well as 4-stroke models F20-F40 manufactured between 1998 and 2011.\u003c\/p\u003e\n\u003cp\u003eThis component provides a direct interchange for Yamaha impeller part numbers 6H4-44352-00\/01\/02 and the impeller within kit 6H4-W0078-00. It also cross-references with aftermarket parts from Sierra (18-3415\/18-3434) and GLM (12276).\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eEngineered for direct OEM replacement to ensure straightforward installation.\u003c\/li\u003e\n\u003cli\u003eImpeller is manufactured from durable, marine-grade rubber for longevity.\u003c\/li\u003e\n\u003cli\u003eProduced in an ISO9002 certified facility to meet high-quality standards.\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 suppliers.\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\u003e6H4-44352-00, 6H4-44352-01, 6H4-44352-02\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha (Full Kit)\u003c\/td\u003e\n        \u003ctd\u003e63D-W0078-00-00, 63D-W0078-01-00, 63D-W0078-02-00, 63D-W0078-03-00\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eSierra\u003c\/td\u003e\n        \u003ctd\u003e18-3415, 18-3434\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eGLM\u003c\/td\u003e\n        \u003ctd\u003e12276\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 and year in the tables below.\u003c\/p\u003e\n\u003cp\u003eThis impeller fits the following Yamaha 2-Stroke and 4-Stroke outboard models.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Yamaha Engine 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\u003e25B, 25J, 25N, 25Q, 25V, 25XMH\u003c\/td\u003e\n        \u003ctd\u003e25\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1996–2002\u003c\/td\u003e\n        \u003ctd\u003e6H4-44352-02\u003c\/td\u003e\n        \u003ctd\u003e3-cylinder engines\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eC30, 30D, 30G, 30H\u003c\/td\u003e\n        \u003ctd\u003e30\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1987–2001\u003c\/td\u003e\n        \u003ctd\u003e6H4-44352-02\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003e40H, 40X\u003c\/td\u003e\n        \u003ctd\u003e40\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1984–1994\u003c\/td\u003e\n        \u003ctd\u003e6H4-44352-02\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003e50D\u003c\/td\u003e\n        \u003ctd\u003e50\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1984–1994\u003c\/td\u003e\n        \u003ctd\u003e6H4-44352-02\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eF20A, F20D\u003c\/td\u003e\n        \u003ctd\u003e20\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1998–2011\u003c\/td\u003e\n        \u003ctd\u003e6H4-44352-02\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eF25A, F25D\u003c\/td\u003e\n        \u003ctd\u003e25\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1998–2011\u003c\/td\u003e\n        \u003ctd\u003e6H4-44352-02\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eFT25B, FT25F\u003c\/td\u003e\n        \u003ctd\u003e25\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e2001–2006\u003c\/td\u003e\n        \u003ctd\u003e6H4-44352-02\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eF30A, F30B\u003c\/td\u003e\n        \u003ctd\u003e30\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e2001–2005\u003c\/td\u003e\n        \u003ctd\u003e6H4-44352-02\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eF40B, F40F\u003c\/td\u003e\n        \u003ctd\u003e40\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e2000–2008\u003c\/td\u003e\n        \u003ctd\u003e6H4-44352-02\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\u003eDirect OEM replacement\u003c\/dd\u003e\n  \u003cdt\u003eMaterial\u003c\/dt\u003e\n\u003cdd\u003eMarine-grade rubber (impeller); aluminum\/stainless steel (housing components)\u003c\/dd\u003e\n  \u003cdt\u003eDimensions\u003c\/dt\u003e\n\u003cdd\u003eImpeller dimensions: 51.2 mm (outer diameter) × 16.1 mm (inner diameter) × 19.05 mm (height)\u003c\/dd\u003e\n  \u003cdt\u003eCertification\u003c\/dt\u003e\n\u003cdd\u003eProduced in ISO9002 certified factory\u003c\/dd\u003e\n\u003c\/dl\u003e\n\n\u003ch2\u003eWhat’s in the Box\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cspan style=\"color:#d0021b;\"\u003e1 x\u003c\/span\u003e Water Pump Impeller (replaces 6H4-44352-02)\u003c\/li\u003e\n  \u003cli\u003eNote: This product contains the impeller only. For the complete water pump repair kit with housing, please reference Yamaha part number 6H4-W0078-00.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n  \u003cli\u003eDisconnect the battery before starting work.\u003c\/li\u003e\n  \u003cli\u003eRemove the lower unit (gearcase) from the outboard motor.\u003c\/li\u003e\n  \u003cli\u003eUnbolt and remove the water pump housing to access the old impeller.\u003c\/li\u003e\n  \u003cli\u003eRemove the old impeller and the Woodruff key from the driveshaft.\u003c\/li\u003e\n  \u003cli\u003eClean the interior of the housing and inspect it and the wear plate for scoring or damage. Replace if necessary.\u003c\/li\u003e\n  \u003cli\u003eInstall the new Woodruff key and slide the new impeller onto the driveshaft, turning it clockwise to bed the vanes.\u003c\/li\u003e\n  \u003cli\u003eRe-install the water pump housing, ensuring any gaskets or o-rings are properly seated.\u003c\/li\u003e\n  \u003cli\u003eRe-attach the lower unit to the outboard and torque bolts to manufacturer specifications.\u003c\/li\u003e\n  \u003cli\u003eStart the engine in water and confirm a steady stream from the \"tell-tale\" outlet.\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 impeller fits my Yamaha outboard?\u003c\/summary\u003e\n  \u003cp\u003eFirst, check your engine model, horsepower, and year against the detailed compatibility table on this page. Second, it is always best practice to visually compare our product photos with your existing part before ordering to ensure an exact match.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat are the signs of a failing water pump impeller?\u003c\/summary\u003e\n  \u003cp\u003eThe most common symptoms are engine overheating at idle or low speeds and a weak or non-existent water stream from the \"tell-tale\" indicator. Upon inspection, a worn impeller may have cracked, brittle, or permanently curved 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 crucial part of preventative maintenance, we recommend inspecting the impeller annually and replacing it every 1-2 years or every 100-200 hours of operation. Service intervals should be shorter in saltwater or silty conditions.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eDoes this kit include the housing, gaskets, or wear plate?\u003c\/summary\u003e\n  \u003cp\u003eNo, this listing is for the flexible rubber impeller only, which corresponds to Yamaha part number 6H4-44352-02. For a complete service kit that includes the housing, gaskets, and plate, please look for Yamaha kit number 6H4-W0078-00.\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\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50723798253883,"sku":"23KY081","price":19.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/Water_Pump_Impeller_Kit_for_Yamaha_40_-_50_HP_6H4-44352_-_JLM_MARINE-8289023.jpg?v=1763032059","url":"https:\/\/seasierra.com\/products\/water-pump-impeller-kit-fits-yamaha-25-50-hp-replaces-6h4-44352-6h4-w0078-00","provider":"SeaSierra","version":"1.0","type":"link"}