{"product_id":"water-pump-repair-kit-fits-yamaha-25-30-hp-2-stroke-replaces-6j8-w0078-a2-00-879136","title":"Water Pump Repair Kit – Fits Yamaha 25\/30 HP 2-Stroke (Replaces 6J8-W0078-A2-00, 879136)","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 25\/30 HP Outboard Motors (Replaces 6J8-W0078-A2-00)\u003c\/strong\u003e is engineered for Yamaha 25 HP (1999, 2001–2002) \u0026amp; 30 HP (1997–1999, 2001–2002) 2-Stroke outboard motors. It provides all essential components to restore your engine's cooling system performance.\u003c\/p\u003e\n\u003cp\u003eIt serves as a direct interchange for Yamaha 6J8-W0078-A2-00, 6J8-W0078-A1-00, 6J8-W0078-C2-00, Mercury 879136, Sierra 18-3430, and GLM 12285\/12284.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInstallation Location:\u003c\/strong\u003e Mounts in the lower unit.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFitment:\u003c\/strong\u003e Direct replacement fit.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eImportant Note:\u003c\/strong\u003e The kit does not include the water pump housing unless specifically noted.\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\u003e6J8-W0078-A2-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6J8-W0078-A1-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6J8-W0078-C2-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMercury\u003c\/td\u003e\n\u003ctd\u003e879136\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-3430\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eGLM\u003c\/td\u003e\n\u003ctd\u003e12285\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eGLM\u003c\/td\u003e\n\u003ctd\u003e12284\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 engines, this kit fits various 25 HP and 30 HP models from the late 1980s through the early 2000s.\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\u003e25\u003c\/td\u003e\n        \u003ctd\u003e25\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1999\u003c\/td\u003e\n        \u003ctd\u003e6J8-W0078-A2-00\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003e25\u003c\/td\u003e\n        \u003ctd\u003e25\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e2001–2002\u003c\/td\u003e\n        \u003ctd\u003e6J8-W0078-A2-00\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003e30\u003c\/td\u003e\n        \u003ctd\u003e30\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1997–1999\u003c\/td\u003e\n        \u003ctd\u003e6J8-W0078-A2-00\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003e30\u003c\/td\u003e\n        \u003ctd\u003e30\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e2001–2002\u003c\/td\u003e\n        \u003ctd\u003e6J8-W0078-A2-00\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003e30\u003c\/td\u003e\n        \u003ctd\u003e30\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1987, 1989–1993, 1996\u003c\/td\u003e\n        \u003ctd\u003e6J8-W0078-A1-00\u003c\/td\u003e\n        \u003ctd\u003eJapanese Engine\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\u003eLower Unit\u003c\/dd\u003e\n  \u003cdt\u003eFitting Type\u003c\/dt\u003e\n\u003cdd\u003eDirect Fit\u003c\/dd\u003e\n  \u003cdt\u003eOther Technical Attributes\u003c\/dt\u003e\n\u003cdd\u003eKit does not include housing unless specifically noted\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 Cartridge Insert (663-44322-00-00)\u003c\/li\u003e\n  \u003cli\u003e1 x Impeller (6H4-44352-02-00)\u003c\/li\u003e\n  \u003cli\u003e1 x Water Pump Gasket (663-44315-A0-00)\u003c\/li\u003e\n  \u003cli\u003e1 x Outer Plate, Cartridge (663-44323-00-00)\u003c\/li\u003e\n  \u003cli\u003e1 x Gasket, Cartridge (663-44324-A0-00)\u003c\/li\u003e\n  \u003cli\u003e1 x Water Pump Gasket (663-44316-A0-00)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cspan style=\"color:#d0021b;\"\u003e2 x\u003c\/span\u003e Bolt, With Washer (90119-08M13-00)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cspan style=\"color:#d0021b;\"\u003e2 x\u003c\/span\u003e Bolt, With Washer (90119-08M34-00)\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 neutral.\u003c\/li\u003e\n  \u003cli\u003eRemove the lower unit (gearcase) from the outboard's midsection, placing it on a stable workbench.\u003c\/li\u003e\n  \u003cli\u003eUnbolt and remove the water pump housing, taking note of the order of all components.\u003c\/li\u003e\n  \u003cli\u003eRemove the old impeller, gaskets, plates, and seals.\u003c\/li\u003e\n  \u003cli\u003eThoroughly clean all mating surfaces, ensuring they are free of old gasket material and corrosion.\u003c\/li\u003e\n  \u003cli\u003eInstall the new components from the kit in the reverse order of disassembly. Apply a light coat of marine grease to the new impeller and inside the housing.\u003c\/li\u003e\n  \u003cli\u003eEnsure the impeller vanes are oriented correctly (typically by turning the driveshaft clockwise during installation).\u003c\/li\u003e\n  \u003cli\u003eReinstall the water pump housing and torque the bolts to the manufacturer's specifications.\u003c\/li\u003e\n  \u003cli\u003eReattach the lower unit, carefully aligning the driveshaft, shift shaft, and water tube.\u003c\/li\u003e\n  \u003cli\u003eReconnect the battery and test the engine on a water source (flushing attachment or test tank) to confirm proper water flow from the 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 specific engine model?\u003c\/summary\u003e\n  \u003cp\u003eVerify your engine's model, horsepower, and year against the \"Engine \u0026amp; Model Compatibility\" table. For the most accurate match, cross-reference your existing part number with our \"Part Number Matrix.\"\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat are the signs of a failing water pump?\u003c\/summary\u003e\n  \u003cp\u003eCommon indicators include a weak or intermittent water stream from the engine's \"tell-tale\" port, engine overheating alarms, or a discovery of a brittle, cracked, or melted impeller during routine inspection.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow often should the water pump impeller be replaced?\u003c\/summary\u003e\n  \u003cp\u003eFor preventative maintenance, we recommend inspecting and replacing the impeller every 1-2 years or every 100-200 hours of operation. Service intervals should be shorter in saltwater or silty\/sandy conditions.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eDoes this kit include the water pump housing?\u003c\/summary\u003e\n  \u003cp\u003eNo, this is a repair kit containing the impeller and related gaskets, plates, and hardware. The housing is not included unless explicitly listed in the \"What's in the Box\" section.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhy are there two different sets of bolts included?\u003c\/summary\u003e\n  \u003cp\u003eManufacturers may use different length bolts across various model years and production runs. This kit includes the most common variations to ensure you have the correct hardware for your specific lower unit.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat is the difference between OEM and aftermarket parts?\u003c\/summary\u003e\n  \u003cp\u003eThis listing is for an aftermarket replacement part, not an original equipment manufacturer (OEM) component. It is built to meet or exceed OEM-level specifications with comparable materials. Our parts are manufactured in an ISO 9002 certified facility and are batch-inspected for quality and consistency.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow fast is shipping?\u003c\/summary\u003e\n  \u003cp\u003eWe ship worldwide, with typical transit times of 5–15 days for most regions. Standard shipping is free, and expedited options are available at checkout where applicable.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat is the warranty and return policy?\u003c\/summary\u003e\n  \u003cp\u003eThis product is covered by a 1-year warranty against manufacturing defects under normal use. If you encounter an issue, please contact our support team with your order details. Returns are accepted within our standard window for unused items in their original condition. Please see our full policy page or contact us 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 and specifications against your original part before ordering. If anything differs—even if your model is listed as compatible—do not purchase.\u003c\/li\u003e\n  \u003cli\u003eThis is an aftermarket replacement part, not an OEM component.\u003c\/li\u003e\n  \u003cli\u003eProfessional installation is highly recommended for safety, proper function, and to prevent engine damage.\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 rigorously tested for real-world reliability.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFast Global Fulfillment\u003c\/strong\u003e — We offer free standard delivery to most regions worldwide, typically arriving in 5–15 days.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer-Direct Value\u003c\/strong\u003e — By working directly with manufacturers, we provide fair pricing without ever compromising on materials or quality control.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50723800154427,"sku":"17KY002","price":37.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/Water_Pump_Impeller_Kit_for_Yamaha_25HP-30HP_6J8-W0078_-_JLM_MARINE-8288947.jpg?v=1763032133","url":"https:\/\/seasierra.com\/products\/water-pump-repair-kit-fits-yamaha-25-30-hp-2-stroke-replaces-6j8-w0078-a2-00-879136","provider":"SeaSierra","version":"1.0","type":"link"}