{"product_id":"water-pump-repair-kit-fits-yamaha-40hp-2-stroke-replaces-679-w0078-a1-00-6f5-w0078-a0-00","title":"Water Pump Repair Kit – Fits Yamaha 40HP 2-Stroke (Replaces 679-W0078-A1-00, 6F5-W0078-A0-00)","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 \u003cstrong\u003eWater Pump Repair Kit – Fits Yamaha 40HP 2-Stroke (Replaces 679-W0078-A1-00, 6F5-W0078-A0-00)\u003c\/strong\u003e provides all essential components to service and restore your outboard's cooling system. It is designed for Yamaha 2-Stroke 40HP models including C40 and CV40 (1990–1997) and select Mariner 40HP 2-Stroke models.\u003c\/p\u003e\n\u003cp\u003eThis kit serves as a direct interchange for Yamaha part numbers 679-W0078-A1-00, 6F5-W0078-A0-00, Sierra 18-3397, and Mallory 9-48604, among others.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eEngineered as a direct OEM-spec replacement for a precise fit.\u003c\/li\u003e\n\u003cli\u003eIncludes all necessary gaskets, seals, impeller, and hardware for a complete water pump overhaul.\u003c\/li\u003e\n\u003cli\u003eNote: The water pump housing is not included with this kit and must be purchased separately if needed.\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\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e679-W0078-A1-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e679-W0078-A0-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e679-W0078-00-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e679-W0078-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6F5-W0078-A0-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-3397\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-3398\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMallory\u003c\/td\u003e\n\u003ctd\u003e9-48604\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\u003eFor Yamaha models, this kit fits various C40 and CV40 outboards from 1990 to 1997. Please verify your specific model and year.\u003c\/p\u003e\n\u003cp\u003eThis kit is compatible with select 40HP 2-stroke Mariner outboards that use OEM part numbers 84363M, 84363T, or 99971M. Verify your engine's requirements 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\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\u003eCV40ELD\u003c\/td\u003e\n\u003ctd\u003e40\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1990\u003c\/td\u003e\n\u003ctd\u003e6F5-W0078-A0-00\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eCV40EL\u003c\/td\u003e\n\u003ctd\u003e40\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1990\u003c\/td\u003e\n\u003ctd\u003e6F5-W0078-A0-00\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eC40ELR\u003c\/td\u003e\n\u003ctd\u003e40\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1991–1997\u003c\/td\u003e\n\u003ctd\u003e679-W0078-A1-00\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eC40ESH\u003c\/td\u003e\n\u003ctd\u003e40\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1997\u003c\/td\u003e\n\u003ctd\u003e679-W0078-A1-00\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eC40MLH\u003c\/td\u003e\n\u003ctd\u003e40\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1994–1995\u003c\/td\u003e\n\u003ctd\u003e679-W0078-A1-00\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eC40MSH\u003c\/td\u003e\n\u003ctd\u003e40\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1992–1997\u003c\/td\u003e\n\u003ctd\u003e679-W0078-A1-00\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eC40PLR\u003c\/td\u003e\n\u003ctd\u003e40\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1992–1997\u003c\/td\u003e\n\u003ctd\u003e679-W0078-A1-00\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMariner\u003c\/td\u003e\n\u003ctd\u003e40HP (selected models)\u003c\/td\u003e\n\u003ctd\u003e40\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e\u003c\/td\u003e\n\u003ctd\u003e84363M, 84363T, 99971M\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 Repair Kit\u003c\/dd\u003e\n  \u003cdt\u003eInstallation\u003c\/dt\u003e\n\u003cdd\u003eDirect OEM replacement\u003c\/dd\u003e\n  \u003cdt\u003eHousing\u003c\/dt\u003e\n\u003cdd\u003eNot included (housing sold separately)\u003c\/dd\u003e\n  \u003cdt\u003eKit Contents\u003c\/dt\u003e\n\u003cdd\u003eIncludes all necessary gaskets, seals, impeller, and hardware for water pump service\u003c\/dd\u003e\n\u003c\/dl\u003e\n\n\u003ch2\u003eWhat’s in the Box\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e1 × Water Seal (663-44366-00-00)\u003c\/li\u003e\n  \u003cli\u003e1 × Water Pump Gasket (676-44315-A0-00\/676-44315-A1-00)\u003c\/li\u003e\n  \u003cli\u003e1 × Insert Cup (676-44322-00-00)\u003c\/li\u003e\n  \u003cli\u003e1 × Outer Plate, Cartridge (676-44323-00-00)\u003c\/li\u003e\n  \u003cli\u003e1 × Cartridge Gasket (676-44324-A0-00\/676-44324-A1-00)\u003c\/li\u003e\n  \u003cli\u003e1 × Water Pump Gasket (679-44316-A0-00\/679-44316-A1-00)\u003c\/li\u003e\n  \u003cli\u003e1 × Impeller (6F5-44352-00-00)\u003c\/li\u003e\n  \u003cli\u003e1 × Woodruff Key (90280-04M00-00)\u003c\/li\u003e\n  \u003cli\u003e\u003cspan style=\"color:#d0021b;\"\u003e4 × Washer, Plain (92990-08600-00)\u003c\/span\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003cspan style=\"color:#d0021b;\"\u003e2 × Bolt, Hexagon (97095-08045-00)\u003c\/span\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003cspan style=\"color:#d0021b;\"\u003e2 × Bolt, Hexagon (97095-08055-00)\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n  \u003cli\u003eDisconnect the negative battery cable for safety.\u003c\/li\u003e\n  \u003cli\u003eUnbolt and remove the lower unit (gearcase) from the outboard's midsection. Keep track of all hardware.\u003c\/li\u003e\n  \u003cli\u003ePlace the lower unit on a suitable workbench. Remove the bolts securing the water pump housing.\u003c\/li\u003e\n  \u003cli\u003eLift the housing and remove the old impeller, gaskets, wear plate, and seals. Note the orientation of the impeller vanes.\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 components from the kit in the reverse order of disassembly. Lightly grease the new seals and gaskets.\u003c\/li\u003e\n  \u003cli\u003eWhen installing the new impeller, turn the driveshaft in its normal direction of rotation to correctly seat the vanes inside the cup.\u003c\/li\u003e\n  \u003cli\u003eReassemble the pump housing and torque its bolts to the manufacturer's specifications.\u003c\/li\u003e\n  \u003cli\u003eReinstall the lower unit onto the midsection, ensuring the driveshaft, shift shaft, and water tube align correctly.\u003c\/li\u003e\n  \u003cli\u003eOnce assembled, test the engine using a water supply (flushing muffs or in water) to confirm that water is pumping correctly from the tell-tale outlet.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\u003csummary\u003eHow do I know if this kit fits my specific engine?\u003c\/summary\u003e\u003cp\u003eThis kit is designed for Yamaha 40HP 2-Stroke C40 and CV40 models from 1990–1997 and select 40HP Mariner outboards. The most reliable way to confirm fitment is to match your engine's model and serial number against our compatibility table and cross-reference the OEM part number.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eDoes this kit include the water pump housing?\u003c\/summary\u003e\u003cp\u003eNo, this kit contains the internal service components (impeller, gaskets, seals, plates, hardware) but does not include the upper or lower water pump housing. Housings are sold separately.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat are the common signs of a failing water pump?\u003c\/summary\u003e\u003cp\u003eA weak or non-existent water stream from the \"tell-tale\" outlet is the most common sign. Other indicators include engine overheating alarms, steam from the exhaust, or a prematurely worn or melted impeller discovered during inspection.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eHow often should I replace my water pump impeller?\u003c\/summary\u003e\u003cp\u003eAs a key part of preventative maintenance, we recommend servicing the water pump every 100 hours of use or annually, whichever comes first. This interval should be shortened if the engine is operated in sandy, silty, or saltwater environments.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eThe part number on my old part is 6F5-W0078-A0-00. Will this kit work?\u003c\/summary\u003e\u003cp\u003eYes, this kit is a direct aftermarket replacement for Yamaha OEM part number 6F5-W0078-A0-00, along with several other superseded numbers like 679-W0078-A1-00. Please see our Part Number Matrix for a full list of cross-references.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eIs any special grease needed for installation?\u003c\/summary\u003e\u003cp\u003eWhile not included, applying a thin layer of marine-grade, water-insoluble grease to the impeller, seals, and inside the pump cup can ease installation and improve initial priming. Do not use petroleum-based grease on rubber components.\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":50723971957051,"sku":"23KY090","price":21.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/Water_Pump_Impeller_Kit_for_Yamaha_40HP_6F5-W0078-A0_-_JLM_MARINE-8289065.jpg?v=1763038832","url":"https:\/\/seasierra.com\/products\/water-pump-repair-kit-fits-yamaha-40hp-2-stroke-replaces-679-w0078-a1-00-6f5-w0078-a0-00","provider":"SeaSierra","version":"1.0","type":"link"}