{"title":"Yamaha 2-Stroke Outboard Engine 25-50HP Parts","description":"\u003csection id=\"hero\" style=\"padding:16px;border:1px solid #e5e7eb;border-radius:8px;\"\u003e\n  \u003cp\u003eThis page is tailored for Yamaha 2‑Stroke 25–50HP outboard engines. Use it to find compatible parts and quick service guidance. Below you’ll find maintenance tips, frequently replaced components, troubleshooting checklists, and links to parts. You can also browse the main Yamaha collection. Scroll to the bottom of the page to start browsing parts for this engine, and remember that on the collection page you can 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\/yamaha-outboard-parts\" style=\"display:inline-block;margin-top:8px;padding:10px 14px;background:#0ea5e9;color:#fff;text-decoration:none;border-radius:6px;\"\u003eBrowse All Yamaha Parts\u003c\/a\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"identify-model\" style=\"margin-top:24px;\"\u003e\n  \u003ch2\u003eHow to Identify Your 25–50HP Model\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eLocate the identification plate or sticker on the mounting bracket or swivel bracket. It lists the model code, serial number, and often the shaft length.\u003c\/li\u003e\n    \u003cli\u003eRead the model code suffix letters: common suffixes indicate shaft length (S\/L\/X), starting and control type (M = manual, E = electric start, R = remote), and other options.\u003c\/li\u003e\n    \u003cli\u003eConfirm stroke\/platform: these are 2‑stroke engines. Many 40\/50HP (and some 25\/30 variants) are inline‑3; other 25\/30 models are inline‑2. Compare cylinder count and cowl decals to verify.\u003c\/li\u003e\n    \u003cli\u003eNote oiling method: some 2‑stroke models are pre‑mix; others have oil‑injection. Check for an oil tank and pump lines if equipped.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"engine-overview\" style=\"margin-top:24px;\"\u003e\n  \u003ch2\u003ePlatform Overview\u003c\/h2\u003e\n\n  \u003ch3\u003eInline‑3 Carbureted 2‑Stroke (Common on 40\/50HP; some 25\/30 variants)\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 #e5e7eb;\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;\"\u003eDescription\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eInline‑3, carbureted 2‑stroke with conventional reed induction.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eExamples include 40\/50HP 2‑stroke families (e.g., C40\/C50) and certain 25\/30HP variants found in some markets.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eGood power‑to‑weight ratio and strong mid‑range torque; simple, serviceable ignition and fuel systems.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eParts often interchange across mid‑to‑late 1990s through 2000s sub‑models, but always match parts by full model code and serial range.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\n  \u003ch3\u003eInline‑2 Carbureted 2‑Stroke (Common on many 25\/30HP)\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 #e5e7eb;\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;\"\u003eDescription\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eInline‑2, carbureted 2‑stroke; simple layout, light weight.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eTypical 25\/30HP 2‑stroke models (various regional codes), manual or electric start, tiller or remote.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eVery serviceable; fewer parts, easy carb and ignition access; ideal for light skiffs and tenders.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eCooling and gearcase service parts are broadly shared across years, but gaskets and ignition items can be year‑specific—verify by model\/serial.\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=\"margin-top:24px;\"\u003e\n  \u003ch2\u003eRoutine Maintenance \u0026amp; Service Parts\u003c\/h2\u003e\n  \u003cp\u003eIntervals below are general guidelines for 2‑stroke outboards; always follow the official Yamaha service manual for your exact model and duty cycle.\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 #e5e7eb;\"\u003eItem\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;\"\u003eInterval*\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;\"\u003eRemarks\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;\"\u003eParts Link\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eLower unit gear oil\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eDrain, inspect magnet for metal, refill with marine gear lube; replace seals if water intrusion is found.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-lower-unit-seal-kits\"\u003eYamaha Lower Unit Seal Kits\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eSpark plugs\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eInspect every 50 hours; replace 100 hours\/season\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eUse correct heat range and gap; replace if fouled, worn, or cracked.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\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:6px 0;\"\u003eFuel filter \/ water separation\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eEvery 100 hours or sooner in contaminated fuel\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eReplace the inline filter; consider a water‑separating filter on the boat for ethanol fuels.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\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:6px 0;\"\u003eWater pump impeller \/ kit\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eEvery 2 seasons or 200 hours\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eReplace impeller regularly; use a full kit if housing wear or salt scaling is present.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-water-pump-repair-kits\"\u003eYamaha Water Pump Repair Kits\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eAnodes (external \u0026amp; internal)\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eInspect every 50 hours; replace when 50% gone\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eUse the correct alloy (salt vs. brackish\/fresh). Keep mounting surfaces clean.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-anodes\"\u003eYamaha Anodes\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e2‑Stroke fuel\/oil setup\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eEvery service; before each season\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eConfirm correct pre‑mix ratio if applicable, or inspect oil‑injection tank, lines, and pump indexing on injected models.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-outboard-parts\"\u003eYamaha Outboard Parts\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003ePropeller \u0026amp; hub inspection\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eEvery 50–100 hours\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eRemove prop to check for fishing line; inspect thrust washer and hub condition.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-propellers\"\u003eYamaha Propellers\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n  \u003cp style=\"font-size:12px;color:#6b7280;\"\u003e*Intervals vary by environment and duty cycle; follow your engine’s official maintenance schedule.\u003c\/p\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"common-parts\" style=\"margin-top:24px;\"\u003e\n  \u003ch2\u003eFrequently Used Parts Categories\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eRoutine Service – \u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-service-maintenance-kits\"\u003eYamaha Service \u0026amp; Maintenance Kits\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCooling System – \u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-water-pump-repair-kits\"\u003eYamaha Water Pump Repair Kits\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eGearcase \u0026amp; Seals – \u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-lower-unit-seal-kits\"\u003eYamaha Lower Unit Seal Kits\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eIgnition \/ Electrical – \u003ca href=\"https:\/\/seasierra.com\/collections\/spark-plug\"\u003eSpark Plugs\u003c\/a\u003e and \u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-starters\"\u003eYamaha Starters\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 and \u003ca href=\"https:\/\/seasierra.com\/collections\/fuel-pumps\"\u003eFuel Pumps\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCorrosion Protection – \u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-anodes\"\u003eYamaha Anodes\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eGaskets \u0026amp; Seals – \u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-gaskets\"\u003eYamaha Gaskets\u003c\/a\u003e and \u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-oil-seals\"\u003eYamaha Oil Seals\u003c\/a\u003e\n\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"troubleshooting\" style=\"margin-top:24px;\"\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 #e5e7eb;\"\u003eSymptom\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;\"\u003eCheck First\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;\"\u003eRelated Parts\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eWeak tell‑tale stream or overheat alarm\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eInspect intake screens for debris; verify impeller condition; check thermostat and tell‑tale hose for blockage.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eWater pump kit, impeller, thermostat, intake screen\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003ePoor acceleration or power loss\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eCheck for fouled plugs, water in fuel, clogged filter; verify prop pitch\/damage; ensure full throttle opening and carb sync.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eSpark plugs, fuel filter, carburetor service kit, propeller\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eHard starting or rough idle\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eConfirm primer bulb firmness and no air leaks; inspect choke\/enrichment function; clean idle circuits.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eFuel lines, primer bulb, carburetor kit, spark plugs\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eExcessive smoke (2‑stroke)\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eVerify correct fuel\/oil ratio; check for stuck choke; confirm oil‑pump indexing on injection models.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eChoke components, oil pump\/lines, spark plugs\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eGearcase noise or metal in gear oil\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eCheck oil level\/condition; pressure test gearcase; inspect prop‑shaft seals for fishing line damage.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eSeals, bearings, gear lube, thrust washer\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=\"margin-top:24px;\"\u003e\n  \u003ch2\u003eFAQs\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eAre parts interchangeable across different years or platforms?\u003c\/summary\u003e\n    \u003cp\u003eSome service items (impellers, anodes, gearcase seals) are shared, but ignition, gaskets, and some cooling parts may differ between inline‑2 and inline‑3 platforms and by year\/serial range. Always match parts using the full model code and serial number.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhen should I replace the impeller?\u003c\/summary\u003e\n    \u003cp\u003eInspect annually and replace every 2 seasons or about 200 hours. Replace sooner if the tell‑tale weakens, you ran through sand, or the pump was dry‑started.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow often should I change the gear oil?\u003c\/summary\u003e\n    \u003cp\u003eAt least every 100 hours or annually. If the oil looks milky or you see metal on the drain‑plug magnet, service the seals and inspect bearings immediately.\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 full model code, serial number, shaft length (S\/L\/X), control type (tiller or remote), and whether the engine is pre‑mix or oil‑injected.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"cta\" style=\"margin-top:24px;\"\u003e\n  \u003cp\u003eReady to find parts by horsepower, year, and model? Browse the main Yamaha collection to filter and sort the results for your 2‑stroke 25–50HP engine.\u003c\/p\u003e\n  \u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-outboard-parts\" style=\"display:inline-block;margin:8px 0 4px;padding:10px 14px;background:#0ea5e9;color:#fff;text-decoration:none;border-radius:6px;\"\u003eShop Yamaha Outboard Parts\u003c\/a\u003e\n  \u003cp style=\"font-size:12px;color:#6b7280;\"\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":"water-pump-impeller-kit-fits-yamaha-25-50-hp-replaces-6h4-44352-6h4-w0078-00","title":"Water Pump Impeller – Fits Yamaha 25–50 HP 2-Stroke Outboards","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 {\n    padding:10px 12px; border:1px solid #e5e7eb; text-align:left; vertical-align:top;\n  }\n  table.ss-table th {\n    white-space:nowrap;\n    word-break:normal;\n    letter-spacing:normal;\n    font-weight:600;\n    background:#f8fafc;\n  }\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\u003c\/strong\u003e is a direct-fit replacement for selected Yamaha 25–50 HP 2-stroke outboard water pump applications. The flexible marine-grade rubber impeller is designed to restore water-pump circulation and help maintain proper engine cooling.\u003c\/p\u003e\n\u003cp\u003eThis impeller corresponds to Yamaha water pump impeller reference \u003cstrong\u003e6H4-44352-02\u003c\/strong\u003e and is associated with water pump service reference \u003cstrong\u003e6H4-W0078-00\u003c\/strong\u003e. Always compare the original impeller, keyway, engine model, year, and serial-number range before ordering.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eAftermarket replacement for the water pump impeller.\u003c\/li\u003e\n  \u003cli\u003eDurable marine-grade rubber construction for regular marine service.\u003c\/li\u003e\n  \u003cli\u003eDesigned for straightforward replacement when the existing pump housing and related components are serviceable.\u003c\/li\u003e\n  \u003cli\u003eSuitable for preventative maintenance or replacement of a worn impeller.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Number References\u003c\/h2\u003e\n\u003cp\u003eUse the following references to help compare the replacement with your existing part and service information.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Part Number References\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eBrand or Reference\u003c\/th\u003e\n        \u003cth\u003ePart Number\u003c\/th\u003e\n        \u003cth\u003eReference Type\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\u003e6H4-44352-02\u003c\/td\u003e\n        \u003ctd\u003eWater pump impeller reference\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003e6H4-W0078-00\u003c\/td\u003e\n        \u003ctd\u003eWater pump service reference\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        \u003ctd\u003eRelated catalog references; verify component scope before purchase\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eGLM\u003c\/td\u003e\n        \u003ctd\u003e12276\u003c\/td\u003e\n        \u003ctd\u003eRelated aftermarket reference; verify component scope before purchase\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eEngine Compatibility\u003c\/h2\u003e\n\u003cp\u003eThis impeller is intended for selected Yamaha 25–50 HP 2-stroke outboards using the 6H4 impeller pattern. Model, year, shaft configuration, and serial-number conditions can affect fitment, so confirm the complete engine identification before ordering.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Yamaha Engine Compatibility\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eBrand\u003c\/th\u003e\n        \u003cth\u003eRated Horsepower\u003c\/th\u003e\n        \u003cth\u003eStroke\u003c\/th\u003e\n        \u003cth\u003eImpeller Reference\u003c\/th\u003e\n        \u003cth\u003eFitment Note\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\u003e25–50 HP\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e6H4-44352-02\u003c\/td\u003e\n        \u003ctd\u003eSelected applications; confirm exact model, year, and serial number\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\u003cp\u003eDo not use the broad horsepower range alone as confirmation of fitment. Compare your original part and consult the applicable Yamaha parts diagram or service information for the exact engine.\u003c\/p\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003cdl\u003e\n  \u003cdt\u003eProduct Type\u003c\/dt\u003e\n  \u003cdd\u003eWater pump impeller\u003c\/dd\u003e\n  \u003cdt\u003eApplication\u003c\/dt\u003e\n  \u003cdd\u003eSelected Yamaha 25–50 HP 2-stroke outboards\u003c\/dd\u003e\n  \u003cdt\u003eConstruction\u003c\/dt\u003e\n  \u003cdd\u003eMarine-grade rubber impeller\u003c\/dd\u003e\n  \u003cdt\u003eImpeller Dimensions\u003c\/dt\u003e\n  \u003cdd\u003e51.2 mm outer diameter × 16.1 mm inner diameter × 19.05 mm height\u003c\/dd\u003e\n  \u003cdt\u003eReplacement Scope\u003c\/dt\u003e\n  \u003cdd\u003eImpeller only; not a complete water pump repair kit\u003c\/dd\u003e\n  \u003cdt\u003eProduct Status\u003c\/dt\u003e\n  \u003cdd\u003eAftermarket replacement, not an OEM-manufactured component\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\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eNot included:\u003c\/strong\u003e water pump housing, wear plate, gaskets, O-rings, Woodruff key, bolts, or other water pump repair-kit components unless specifically shown and stated in the order details.\u003c\/p\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n  \u003cli\u003eDisconnect the battery and follow the outboard manufacturer's safety procedures.\u003c\/li\u003e\n  \u003cli\u003eRemove the lower unit according to the service instructions for your exact engine.\u003c\/li\u003e\n  \u003cli\u003eRemove the water pump cover or housing to access the old impeller.\u003c\/li\u003e\n  \u003cli\u003eRemove the old impeller and inspect the drive key, keyway, housing, wear plate, gaskets, and seals.\u003c\/li\u003e\n  \u003cli\u003eClean the pump area and replace any damaged or worn related components before reassembly.\u003c\/li\u003e\n  \u003cli\u003eInstall the drive key and new impeller on the driveshaft. Turn the impeller in the correct direction as the housing is installed so the vanes seat properly.\u003c\/li\u003e\n  \u003cli\u003eReinstall the housing, cover, and sealing components using the manufacturer's torque specifications.\u003c\/li\u003e\n  \u003cli\u003eReattach the lower unit and confirm that all fasteners and connections are secure.\u003c\/li\u003e\n  \u003cli\u003eRun the engine only in an appropriate water supply and verify a steady cooling-water tell-tale stream before normal operation.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow do I confirm that this impeller fits my Yamaha outboard?\u003c\/summary\u003e\n  \u003cp\u003eCheck the complete engine model, horsepower, stroke, year, and serial-number range against the applicable parts information. Also compare the original impeller's outside diameter, inside diameter, height, keyway, and vane configuration with the specifications shown on this page.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat are common signs of a worn water pump impeller?\u003c\/summary\u003e\n  \u003cp\u003eSymptoms may include engine overheating, especially at idle or low speed, a weak or missing tell-tale stream, damaged or permanently curved vanes, or visible cracking and brittleness.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eDoes this listing include a complete water pump repair kit?\u003c\/summary\u003e\n  \u003cp\u003eNo. This listing is for one flexible rubber water pump impeller only. The housing, wear plate, gaskets, O-rings, key, bolts, and other repair components are not included.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eIs this an OEM Yamaha part?\u003c\/summary\u003e\n  \u003cp\u003eNo. This is an aftermarket replacement manufactured to match the applicable impeller dimensions and reference application. Yamaha and other brand names and part numbers are used only to identify compatibility and reference information.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow often should a water pump impeller be replaced?\u003c\/summary\u003e\n  \u003cp\u003eInspect the impeller during scheduled water pump service and replace it when the vanes are cracked, brittle, worn, or permanently deformed. Service more frequently when the outboard operates in saltwater, silty water, or other abrasive conditions.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eCan I install the impeller without replacing the housing?\u003c\/summary\u003e\n  \u003cp\u003eYes, if the housing, wear plate, key, gaskets, and seals are within serviceable condition. Replace any component that is scored, warped, damaged, or excessively worn to avoid premature impeller failure.\u003c\/p\u003e\n\u003c\/details\u003e\n\n\u003ch2\u003eSafety \u0026amp; Important Information\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eConfirm fitment using the complete engine model and serial-number information before purchase.\u003c\/li\u003e\n  \u003cli\u003eCompare the product dimensions and appearance with the original part before installation.\u003c\/li\u003e\n  \u003cli\u003eDo not operate an outboard without an adequate water supply for cooling.\u003c\/li\u003e\n  \u003cli\u003eProfessional installation is recommended when lower-unit removal or water-pump service is unfamiliar.\u003c\/li\u003e\n  \u003cli\u003eThis is an aftermarket replacement and is not manufactured by Yamaha.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMarine Replacement Parts\u003c\/strong\u003e — Practical aftermarket components for routine repair and maintenance.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFitment-Focused Information\u003c\/strong\u003e — Clear reference numbers and application details to support accurate part comparison.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer-Direct Value\u003c\/strong\u003e — Competitive replacement parts selected for everyday marine service.\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"},{"product_id":"water-pump-impeller-kit-fits-yamaha-f50a-4-stroke-replaces-yamaha-6bg-w0078-01-00-sierra-18-3434","title":"Water Pump Repair Kit for Yamaha F30LA and F40LA 4-Stroke Outboards","description":"\u003c!-- 🔧 Table Styles (include only once per page) --\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 {\n    padding:10px 12px; border:1px solid #e5e7eb; text-align:left; vertical-align:top;\n  }\n  table.ss-table th {\n    white-space:nowrap;\n    word-break:normal;\n    letter-spacing:normal;\n    font-weight:600;\n    background:#f8fafc;\n  }\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\u003csection\u003e\n\u003ch2\u003eProduct Details\u003c\/h2\u003e\n\u003cp\u003eThis \u003cstrong\u003eWater Pump Repair Kit\u003c\/strong\u003e is intended for servicing the cooling-system water pump on selected Yamaha 4-stroke outboards, including documented Yamaha F30LA and F40LA applications. Replacing worn water-pump service parts can help restore proper cooling-water circulation and reduce the risk of overheating caused by an aged or damaged pump assembly.\u003c\/p\u003e\n\u003cp\u003eCatalog records identify Yamaha water pump repair kit applications under Yamaha part numbers \u003cstrong\u003e6BG-W0078-00-00\u003c\/strong\u003e and \u003cstrong\u003e6BG-W0078-01-00\u003c\/strong\u003e. The two references appear in different model-year catalog records, so verify the exact model, year, serial number and existing part number before ordering.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eDesigned for water-pump service in the outboard lower unit or gear case.\u003c\/li\u003e\n\u003cli\u003eIntended for selected Yamaha 4-stroke applications listed below.\u003c\/li\u003e\n\u003cli\u003eUse the supplied service parts together with the applicable Yamaha service procedure for your engine.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Number References\u003c\/h2\u003e\n\u003cp\u003eThese are manufacturer reference numbers associated with cataloged applications for this water pump repair kit. They are provided for identification and fitment comparison, not as a guarantee for every Yamaha engine carrying the same horsepower rating.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Part Number References\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eBrand\u003c\/th\u003e\n        \u003cth\u003eReference Part Number\u003c\/th\u003e\n        \u003cth\u003eReference Type\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\u003e6BG-W0078-00-00\u003c\/td\u003e\n        \u003ctd\u003eWater pump repair kit reference\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003e6BG-W0078-01-00\u003c\/td\u003e\n        \u003ctd\u003eWater pump repair kit reference\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\u003eThe table below lists model and year combinations found in engine-parts catalog records for the referenced Yamaha water pump repair kit. Model, year and stroke must be matched together; horsepower alone is not sufficient to confirm fitment.\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\u003eCatalog Year\u003c\/th\u003e\n        \u003cth\u003eReference Part No.\u003c\/th\u003e\n        \u003cth\u003eApplication Note\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\u003eF30LA\u003c\/td\u003e\n        \u003ctd\u003e30\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e2021\u003c\/td\u003e\n        \u003ctd\u003e6BG-W0078-01-00\u003c\/td\u003e\n        \u003ctd\u003eListed in repair-kit and scheduled-service-parts catalogs\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eF40LA\u003c\/td\u003e\n        \u003ctd\u003e40\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e2009\u003c\/td\u003e\n        \u003ctd\u003e6BG-W0078-00-00\u003c\/td\u003e\n        \u003ctd\u003eListed in repair-kit and scheduled-service-parts catalogs\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eF40LA\u003c\/td\u003e\n        \u003ctd\u003e40\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e2021\u003c\/td\u003e\n        \u003ctd\u003e6BG-W0078-01-00\u003c\/td\u003e\n        \u003ctd\u003eListed in repair-kit and scheduled-service-parts catalogs\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eF40JEA\u003c\/td\u003e\n        \u003ctd\u003e40\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e2009 and 2021 catalog records\u003c\/td\u003e\n        \u003ctd\u003e6BG-W0078-00-00 \/ 6BG-W0078-01-00\u003c\/td\u003e\n        \u003ctd\u003eVerify the model-year and serial-number configuration\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eF40JEHA\u003c\/td\u003e\n        \u003ctd\u003e40\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e2009 and 2021 catalog records\u003c\/td\u003e\n        \u003ctd\u003e6BG-W0078-00-00 \/ 6BG-W0078-01-00\u003c\/td\u003e\n        \u003ctd\u003eVerify the model-year and serial-number configuration\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\u003eWater pump repair kit\u003c\/dd\u003e\n  \u003cdt\u003eApplication\u003c\/dt\u003e\n  \u003cdd\u003eSelected Yamaha 4-stroke outboard cooling systems\u003c\/dd\u003e\n  \u003cdt\u003eInstallation Location\u003c\/dt\u003e\n  \u003cdd\u003eLower unit \/ gear case water pump\u003c\/dd\u003e\n  \u003cdt\u003eReference Part Numbers\u003c\/dt\u003e\n  \u003cdd\u003e6BG-W0078-00-00 and 6BG-W0078-01-00\u003c\/dd\u003e\n  \u003cdt\u003eBrand Status\u003c\/dt\u003e\n  \u003cdd\u003eAftermarket replacement; not a Yamaha Genuine OEM part\u003c\/dd\u003e\n\u003c\/dl\u003e\n\n\u003ch2\u003eWhat’s in the Box\u003c\/h2\u003e\n\u003cp\u003eThis listing is for a water pump repair kit. Kit contents can vary by application and supplier configuration. Confirm the included components against the product images and the service-parts list for your exact engine before installation.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eWater pump service components for the listed application\u003c\/li\u003e\n\u003cli\u003eImpeller and associated pump sealing or mounting parts as supplied for the kit configuration\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n\u003cli\u003eConfirm the engine model, year, serial number and existing water-pump part number before disassembly.\u003c\/li\u003e\n\u003cli\u003eDisconnect the negative battery cable and follow the safety instructions in the applicable service manual.\u003c\/li\u003e\n\u003cli\u003ePlace the outboard in neutral and remove the shift-rod connection as required for lower-unit removal.\u003c\/li\u003e\n\u003cli\u003eUnbolt and carefully lower the gear case from the outboard midsection.\u003c\/li\u003e\n\u003cli\u003eRemove the water-pump housing and note the orientation of the impeller, key, plate and sealing components.\u003c\/li\u003e\n\u003cli\u003eRemove old gasket material and clean all mating surfaces without damaging the pump plate or housing.\u003c\/li\u003e\n\u003cli\u003eInstall the replacement service parts in the order and orientation specified by the engine service manual.\u003c\/li\u003e\n\u003cli\u003eWhen fitting the impeller into the housing, rotate the driveshaft in the specified direction so the vanes seat correctly.\u003c\/li\u003e\n\u003cli\u003eApply only the lubricant or sealant specified by the service manual and tighten fasteners to the manufacturer’s torque specifications.\u003c\/li\u003e\n\u003cli\u003eReinstall the lower unit, ensuring correct alignment of the water tube, driveshaft splines and shift shaft.\u003c\/li\u003e\n\u003cli\u003eAfter assembly, run the engine only in an appropriate water supply or test tank and confirm a steady tell-tale stream and normal operating temperature.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow do I confirm that this repair kit fits my engine?\u003c\/summary\u003e\n  \u003cp\u003eMatch your complete Yamaha model designation, model year, stroke type and serial-number range with the compatibility information in this listing and your service manual. Also compare the existing water-pump reference number. F30LA and F40LA applications are documented, but not every Yamaha 30 HP or 40 HP outboard uses the same water-pump parts.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat are common signs of a worn water-pump impeller?\u003c\/summary\u003e\n  \u003cp\u003ePossible symptoms include a weak or absent tell-tale stream, an overheating warning, steam from the exhaust area or abnormal operating temperature. A blocked tell-tale, damaged water tube or other cooling-system fault can produce similar symptoms, so diagnose the complete system.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow often should the water pump be serviced?\u003c\/summary\u003e\n  \u003cp\u003eInspect and service the water pump according to the Yamaha maintenance schedule for your specific engine. Replacement intervals depend on operating hours, storage conditions, saltwater exposure and operation in sandy or silty water.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat is the difference between 6BG-W0078-00-00 and 6BG-W0078-01-00?\u003c\/summary\u003e\n  \u003cp\u003eBoth numbers appear as Yamaha water pump repair kit references in catalog records, but they are associated with different model-year records. Do not assume that the two numbers are interchangeable for every engine; verify the exact application before ordering.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eDoes this listing fit Yamaha F50A models?\u003c\/summary\u003e\n  \u003cp\u003eYamaha F50A was not retained as a confirmed application for this listing because the available catalog records document other F30LA, F40LA, F40JEA and F40JEHA configurations. Confirm your F50A’s exact model-year, serial-number range and original water-pump part number before purchase.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eIs this a Yamaha Genuine OEM part?\u003c\/summary\u003e\n  \u003cp\u003eNo. This listing is for an aftermarket replacement repair kit. Yamaha names and reference numbers are used only to identify the intended application.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eCan I install the kit myself?\u003c\/summary\u003e\n  \u003cp\u003eWater-pump service requires lower-unit removal and correct reassembly of the cooling-water system. Use the correct service manual and torque specifications, or have the work completed by a qualified marine technician.\u003c\/p\u003e\n\u003c\/details\u003e\n\n\u003ch2\u003eSafety \u0026amp; Important Information\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eVerify the complete engine model, year, serial number and existing part number before purchase.\u003c\/li\u003e\n\u003cli\u003eDo not rely on horsepower alone to determine compatibility.\u003c\/li\u003e\n\u003cli\u003eDo not operate an outboard without an adequate water supply for cooling.\u003c\/li\u003e\n\u003cli\u003eInspect the water tube, pump housing, wear plate and mating surfaces during installation; replace damaged parts as needed.\u003c\/li\u003e\n\u003cli\u003eThis is an aftermarket replacement component and is not manufactured or endorsed by Yamaha.\u003c\/li\u003e\n\u003cli\u003eProfessional installation is recommended when the correct service procedure or fitment cannot be confirmed.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMarine Replacement Parts\u003c\/strong\u003e — We supply replacement components for common marine maintenance and repair applications.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication-Focused Listings\u003c\/strong\u003e — Product references and fitment information are provided to help customers compare parts before ordering.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eService Support\u003c\/strong\u003e — Always use the appropriate manufacturer service information when installing engine components.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50723806740795,"sku":"23KY710","price":69.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/23KY710_2_c173d1e5-fca1-4e49-af7a-94a801412f10.jpg?v=1763032274"},{"product_id":"water-pump-impeller-repair-kit-fits-yamaha-4-stroke-f25b-f50a-e40x-replaces-6bg-w0078-01-00-6bg-w0078-00-00","title":"Water Pump Repair Kit – Fits Yamaha F30 and F40 4-Stroke Outboards (Selected 2009–2022 Models) – Replaces 6BG-W0078-00-00 and 6BG-W0078-01-00","description":"\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 {\n    padding:10px 12px; border:1px solid #e5e7eb; text-align:left; vertical-align:top;\n  }\n  table.ss-table th {\n    white-space:nowrap;\n    word-break:normal;\n    letter-spacing:normal;\n    font-weight:600;\n    background:#f8fafc;\n  }\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\u003csection\u003e\n\u003ch2\u003eProduct Details\u003c\/h2\u003e\n\u003cp\u003eThis aftermarket \u003cstrong\u003ewater pump repair kit\u003c\/strong\u003e is designed for selected Yamaha F30 and F40 4-stroke outboard applications. Catalog records identify the water pump repair kit for Yamaha F30LA, F30LEHA, F40JEA, F40JEHA, F40LA, F40LEHA, and related model variants in specific production years. It supplies the components needed to service the water pump and restore proper cooling-system performance.\u003c\/p\u003e\n\u003cp\u003eThe kit is listed as a replacement for Yamaha OEM references \u003cstrong\u003e6BG-W0078-00-00\u003c\/strong\u003e and \u003cstrong\u003e6BG-W0078-01-00\u003c\/strong\u003e. Related aftermarket references include Sierra \u003cstrong\u003e18-3450\u003c\/strong\u003e, GLM \u003cstrong\u003e12510\u003c\/strong\u003e, and JLM \u003cstrong\u003eYHJB-6BG\u003c\/strong\u003e. Always match the complete engine model, year, and existing part number before ordering.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eAftermarket water pump repair kit for selected Yamaha 4-stroke outboards.\u003c\/li\u003e\n  \u003cli\u003eDesigned to renew key water-pump service components.\u003c\/li\u003e\n  \u003cli\u003eHelps restore cooling-water flow when the existing pump components are worn or damaged.\u003c\/li\u003e\n  \u003cli\u003eNot an OEM Yamaha component.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n\u003cp\u003eUse these references as a cross-check against your original part and service information. Number listings are not a substitute for confirming the complete engine application.\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\u003cth\u003eReference Type\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\u003e6BG-W0078-00-00\u003c\/td\u003e\n\u003ctd\u003eOEM reference\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6BG-W0078-01-00\u003c\/td\u003e\n\u003ctd\u003eOEM reference\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-3450\u003c\/td\u003e\n\u003ctd\u003eAftermarket reference\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eGLM\u003c\/td\u003e\n\u003ctd\u003e12510\u003c\/td\u003e\n\u003ctd\u003eAftermarket reference\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eJLM\u003c\/td\u003e\n\u003ctd\u003eYHJB-6BG\u003c\/td\u003e\n\u003ctd\u003eAftermarket reference\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\u003eThe applications below are catalog-supported examples. The same model family can have different parts depending on year, suffix, shaft configuration, or serial-number range. Confirm your exact engine identification before installation.\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\u003eCatalog Year\u003c\/th\u003e\n\u003cth\u003eApplicable Reference\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\u003eF30LA\u003c\/td\u003e\n\u003ctd\u003e30\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e2021–2022\u003c\/td\u003e\n\u003ctd\u003e6BG-W0078-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eF30LEHA\u003c\/td\u003e\n\u003ctd\u003e30\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e2021–2022\u003c\/td\u003e\n\u003ctd\u003e6BG-W0078-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eF40JEA\u003c\/td\u003e\n\u003ctd\u003e40\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e2009–2011 and 2021–2022\u003c\/td\u003e\n\u003ctd\u003e6BG-W0078-00-00 or 6BG-W0078-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eF40JEHA\u003c\/td\u003e\n\u003ctd\u003e40\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e2009–2011 and 2021–2022\u003c\/td\u003e\n\u003ctd\u003e6BG-W0078-00-00 or 6BG-W0078-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eF40LA\u003c\/td\u003e\n\u003ctd\u003e40\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e2009–2011 and 2021–2022\u003c\/td\u003e\n\u003ctd\u003e6BG-W0078-00-00 or 6BG-W0078-01-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eF40LEHA\u003c\/td\u003e\n\u003ctd\u003e40\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e2009–2011\u003c\/td\u003e\n\u003ctd\u003e6BG-W0078-00-00\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eF40SA\u003c\/td\u003e\n\u003ctd\u003e40\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e2021\u003c\/td\u003e\n\u003ctd\u003e6BG-W0078-01-00\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\u003eApplication\u003c\/dt\u003e\n  \u003cdd\u003eSelected Yamaha F30 and F40 4-stroke outboard applications\u003c\/dd\u003e\n  \u003cdt\u003eInstallation\u003c\/dt\u003e\n  \u003cdd\u003eReplacement service part; lower-unit removal is required\u003c\/dd\u003e\n  \u003cdt\u003eBrand Status\u003c\/dt\u003e\n  \u003cdd\u003eAftermarket replacement, not OEM Yamaha\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 cover\u003c\/li\u003e\n  \u003cli\u003e1 x Water pump gasket\u003c\/li\u003e\n  \u003cli\u003e1 x Cartridge insert\u003c\/li\u003e\n  \u003cli\u003e1 x Cartridge outer plate\u003c\/li\u003e\n  \u003cli\u003e1 x Water seal\u003c\/li\u003e\n  \u003cli\u003e1 x Water pump impeller\u003c\/li\u003e\n  \u003cli\u003e4 x Bolts with washers\u003c\/li\u003e\n  \u003cli\u003e1 x Woodruff key\u003c\/li\u003e\n  \u003cli\u003e1 x O-ring\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n  \u003cli\u003eDisconnect the battery and place the outboard in neutral.\u003c\/li\u003e\n  \u003cli\u003eRemove the lower unit from the engine midsection, supporting it securely because it may be heavy.\u003c\/li\u003e\n  \u003cli\u003ePlace the lower unit on a stable workbench and remove the water pump housing.\u003c\/li\u003e\n  \u003cli\u003eNote the orientation of the original components, then remove the old impeller, gaskets, seals, and wear components.\u003c\/li\u003e\n  \u003cli\u003eClean all mating surfaces and remove old gasket material, debris, and corrosion.\u003c\/li\u003e\n  \u003cli\u003eInstall the replacement components in the correct order. Lightly lubricate the impeller as appropriate and turn the driveshaft clockwise during installation.\u003c\/li\u003e\n  \u003cli\u003eReinstall the water pump housing with the seals correctly seated. Tighten fasteners to the manufacturer’s specifications.\u003c\/li\u003e\n  \u003cli\u003eApply suitable marine grease to the driveshaft splines and reinstall the lower unit.\u003c\/li\u003e\n  \u003cli\u003eRun the engine with an appropriate flush attachment and confirm a steady tell-tale stream before returning the boat to service.\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 my water pump impeller is failing?\u003c\/summary\u003e\n  \u003cp\u003eCommon signs include a weak or intermittent tell-tale stream, an overheating warning, or an impeller with cracked, brittle, distorted, or missing vanes. Inspect the complete pump assembly if cooling performance is reduced.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow often should I replace the water pump impeller?\u003c\/summary\u003e\n  \u003cp\u003eInspect the impeller during routine service and replace it when wear, damage, deformation, or loss of flexibility is found. Replacement intervals can be shorter in sandy, silty, or saltwater operating conditions; follow the maintenance schedule for your exact engine.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eMy Yamaha model is not listed. Will this kit fit?\u003c\/summary\u003e\n  \u003cp\u003eDo not rely on horsepower alone. Confirm the complete model designation, year, shaft or length configuration, serial-number range when applicable, and the OEM reference in your service information. The listed references are 6BG-W0078-00-00 and 6BG-W0078-01-00.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eIs this kit difficult to install?\u003c\/summary\u003e\n  \u003cp\u003eInstallation requires removal of the lower unit and correct water-pump assembly. It is suitable for an experienced marine technician or mechanically confident owner. Professional installation is recommended if you are unfamiliar with lower-unit service.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eIs this an OEM Yamaha kit?\u003c\/summary\u003e\n  \u003cp\u003eNo. This is an aftermarket replacement kit intended for the listed applications and reference numbers.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat should I verify before ordering?\u003c\/summary\u003e\n  \u003cp\u003eCompare the old pump assembly, complete engine model, production year, and applicable OEM reference. If any detail differs, confirm compatibility with a Yamaha service manual or qualified marine-parts specialist before purchase.\u003c\/p\u003e\n\u003c\/details\u003e\n\n\u003ch2\u003eSafety \u0026amp; Important Information\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eVerify the complete engine model and year before ordering; model families may use different water-pump parts.\u003c\/li\u003e\n  \u003cli\u003eCompare the replacement components with the original assembly before installation.\u003c\/li\u003e\n  \u003cli\u003eDisconnect the battery before service and support the lower unit securely during removal.\u003c\/li\u003e\n  \u003cli\u003eFollow the engine manufacturer’s torque values, lubrication instructions, and cooling-system test procedure.\u003c\/li\u003e\n  \u003cli\u003eThis is an aftermarket replacement, not an OEM Yamaha component.\u003c\/li\u003e\n  \u003cli\u003eProfessional installation is recommended when lower-unit service experience is limited.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMarine Replacement Parts\u003c\/strong\u003e — We supply aftermarket components for routine marine maintenance and repair.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eApplication-Focused Listings\u003c\/strong\u003e — Product information is organized around engine models, reference numbers, and service use.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePractical Service Support\u003c\/strong\u003e — Confirming the exact model and part reference helps ensure the correct replacement before installation.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50723806773563,"sku":"SIE-17KY005","price":25.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/SIE-17KY005_1_c1868301-6489-4cb0-9c14-d3ecad632ac0.jpg?v=1763032275"}],"url":"https:\/\/seasierra.com\/collections\/yamaha-2-stroke-outboard-engine-25-50hp-parts.oembed","provider":"SeaSierra","version":"1.0","type":"link"}