{"title":"Tohatsu 4-Stroke 2.5-6HP Outboard Marine Engine Parts","description":"\u003csection id=\"hero\" style=\"padding:16px;border:1px solid #e5e7eb;border-radius:8px;max-width:1100px;margin:0 auto 24px auto\"\u003e\n  \u003cp\u003eThis page supports Tohatsu 4-Stroke 2.5–6HP outboard engines and helps you find compatible parts and service information. Below you’ll find maintenance tips, common replacement parts, and troubleshooting guidance. You can also browse our main Tohatsu collection any time. Scroll to the bottom of this page to start browsing parts for these engines, and on the collection page use the Filter \u0026amp; Sort controls to narrow results by horsepower, year range, and part category.\u003c\/p\u003e\n  \u003cp\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/tohatsu-outboard-parts\" style=\"display:inline-block;padding:10px 16px;background:#0b63ce;color:#fff;text-decoration:none;border-radius:6px\"\u003eBrowse All Tohatsu Parts\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"identify-model\" style=\"max-width:1100px;margin:0 auto 24px auto\"\u003e\n  \u003ch2\u003eHow to Identify Your 2.5–6HP Model\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eLocate the capacity plate\/serial label on the transom clamp bracket or swivel bracket; it lists model code and serial number.\u003c\/li\u003e\n    \u003cli\u003eModel codes typically begin with MFS for 4‑stroke Tohatsu. Suffix letters\/numbers indicate shaft length (S\/L\/UL), tiller vs. remote, and feature packages (e.g., charging coil).\u003c\/li\u003e\n    \u003cli\u003e2.5\/3.5HP and 4\/5\/6HP are separate small‑portable platforms; many parts are shared within each platform but may differ across platforms.\u003c\/li\u003e\n    \u003cli\u003eFor accurate parts selection, have the full model code and serial number handy, and confirm any year\/suffix notes in your service manual.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"engine-overview\" style=\"max-width:1100px;margin:0 auto 24px auto\"\u003e\n  \u003ch2\u003ePlatform Overview\u003c\/h2\u003e\n  \u003ch3\u003e2.5–3.5HP Portable Platform\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;padding:8px\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px\"\u003eDescription\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eSingle‑cylinder, carbureted 4‑stroke, manual start; lightweight, portable design.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eExamples include MFS2.5 and MFS3.5 variants (S\/L shaft as applicable).\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eVery light, simple to service, excellent portability for tenders and small inflatables.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eMany wear items are unique to this platform; do not assume interchange with 4\/5\/6HP. Verify shaft length and any feature suffixes.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\n  \u003ch3\u003e4–6HP Portable Platform\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;padding:8px\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px\"\u003eDescription\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eSingle‑cylinder, carbureted 4‑stroke. Many 4\/5\/6HP parts are shared across the family.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eExamples include MFS4, MFS5, and MFS6 variants (short\/long shaft; manual or with charging kit).\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eGood fuel economy, simple maintenance, parts availability, and optional 12V charging on select models.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eMost service items (impeller, plugs, gaskets) cross to 4\/5\/6HP. Confirm model suffix for charging kits and gear ratio differences.\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=\"max-width:1100px;margin:0 auto 24px auto\"\u003e\n  \u003ch2\u003eRoutine Maintenance \u0026amp; Service Parts\u003c\/h2\u003e\n  \u003cp\u003eIntervals below are general guidelines for small 4‑stroke portables. Always follow the procedures and schedule in your official Tohatsu service manual for your exact model and usage.\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;padding:8px\"\u003eItem\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px\"\u003eInterval*\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px\"\u003eRemarks\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px\"\u003eParts Link\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eEngine oil\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eFirst 20 hrs, then every 100 hrs or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eMany 2.5–6HP models do not use a spin‑on filter; change oil with engine warm and verify level per manual.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/tohatsu-outboard-parts\"\u003eTohatsu Outboard Parts\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eGear oil (lower unit)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eEvery 100 hrs or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eInspect for water contamination (milky oil). Replace drain screw gaskets if needed.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/tohatsu-lower-unit-seal-kits\"\u003eTohatsu Lower Unit Seal Kits\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eSpark plugs\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eInspect every 100 hrs; replace as needed or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eVerify correct heat range and gap for your specific model code.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\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:8px;border-bottom:1px solid #f0f2f5\"\u003eFuel filter \/ inline filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eCheck every 50–100 hrs; replace seasonally or if restricted\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eKeep fresh, stabilized fuel. Replace clogged filters to prevent lean running.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\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:8px;border-bottom:1px solid #f0f2f5\"\u003eWater pump impeller \/ kit\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eEvery 2 seasons (or 200 hrs); inspect annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eEssential for cooling. Replace sooner if weak tell‑tale, overheating, or sand ingestion.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/tohatsu-water-pump-repair-kits\"\u003eTohatsu Water Pump Repair Kits\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eAnodes (internal\/external)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eInspect every 3 months; replace when 50% consumed\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eMatch alloy to water type (salt\/brackish\/fresh). Maintain clean electrical connections.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/anodes\"\u003eAnodes\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"common-parts\" style=\"max-width:1100px;margin:0 auto 24px auto\"\u003e\n  \u003ch2\u003eFrequently Used Parts Categories\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eRoutine Service: \u003ca href=\"https:\/\/seasierra.com\/collections\/tohatsu-outboard-parts\"\u003eTohatsu Outboard Parts\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCooling System: \u003ca href=\"https:\/\/seasierra.com\/collections\/tohatsu-water-pump-repair-kits\"\u003eTohatsu Water Pump Repair Kits\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eLower Unit \/ Seals: \u003ca href=\"https:\/\/seasierra.com\/collections\/tohatsu-lower-unit-seal-kits\"\u003eTohatsu Lower Unit Seal Kits\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\n\u003c\/li\u003e\n    \u003cli\u003eIgnition \/ Electrical: \u003ca href=\"https:\/\/seasierra.com\/collections\/electrical-items\"\u003eElectrical Items\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003ePropulsion: \u003ca href=\"https:\/\/seasierra.com\/collections\/propellers\"\u003ePropellers\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCorrosion Protection: \u003ca href=\"https:\/\/seasierra.com\/collections\/anodes\"\u003eAnodes\u003c\/a\u003e\n\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"troubleshooting\" style=\"max-width:1100px;margin:0 auto 24px auto\"\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;padding:8px\"\u003eSymptom\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px\"\u003eCheck First\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px\"\u003eRelated Parts\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eWeak tell‑tale or overheat alarm\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eInspect intake screen, tell‑tale hose for blockage, and impeller condition; verify thermostat operation.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eWater pump kit, thermostat, intake screen components\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eHard starting or rough idle\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eUse fresh fuel, prime properly, verify choke\/enrichment, check spark plug and idle mixture\/idle speed settings.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eSpark plug, fuel filter, carburetor parts\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003ePoor acceleration or power loss\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eCheck propeller for damage, confirm venting on fuel tank, inspect fuel filter and plug, and assess compression if persistent.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003ePropeller, fuel filter, spark plug\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eGearcase noise or metal in gear oil\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eDrain and inspect gear oil; look for water intrusion (milky oil). Check drain\/fill plug gaskets and prop shaft fishing line.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eLower unit seal kit, washers\/gaskets, propeller hardware\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eExcessive exhaust smoke (4‑stroke)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eVerify oil level (not overfilled), correct oil grade, and that engine wasn’t stored tilted with oil migration.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f0f2f5\"\u003eEngine oil\/service supplies\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=\"max-width:1100px;margin:0 auto 24px auto\"\u003e\n  \u003ch2\u003eFAQs\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eAre parts interchangeable between 2.5\/3.5HP and 4\/5\/6HP models?\u003c\/summary\u003e\n    \u003cp\u003eMany items interchange within each platform (2.5\/3.5 or 4\/5\/6), but fewer parts cross between platforms. Always match by full model code and serial number to ensure compatibility.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhen should I replace the water pump impeller?\u003c\/summary\u003e\n    \u003cp\u003eInspect annually and replace every two seasons (or sooner if flow is weak, the engine overheats, or you operate in sandy\/silty water). A complete pump kit is recommended during major service.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow often should I change gear oil in the lower unit?\u003c\/summary\u003e\n    \u003cp\u003eTypically every 100 hours or annually. If you see milky oil or water, service immediately and inspect seals and drain\/fill plug gaskets.\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, and any notable options (e.g., charging kit). A clear photo of the nameplate helps us verify the correct parts quickly.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"cta\" style=\"padding:16px;border:1px solid #e5e7eb;border-radius:8px;max-width:1100px;margin:0 auto 24px auto\"\u003e\n  \u003cp\u003eReady to find parts? Browse the main Tohatsu collection and filter by horsepower, year, and model to quickly narrow to compatible components.\u003c\/p\u003e\n  \u003cp\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/tohatsu-outboard-parts\" style=\"display:inline-block;padding:10px 16px;background:#0b63ce;color:#fff;text-decoration:none;border-radius:6px\"\u003eShop Tohatsu Outboard Parts\u003c\/a\u003e\u003c\/p\u003e\n  \u003cp style=\"font-size:0.95em;color:#374151\"\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-fits-tohatsu-nissan-2-5-6-hp-replaces-369-65021-1-47-16154-3","title":"Water Pump Impeller with Key – Fits Tohatsu\/Nissan 2–5 HP 2-Stroke, MFS4–6 HP 4-Stroke and Mercury\/Mariner 2–3.5 HP 4-Stroke","description":"\u003csection\u003e\n  \u003ch2\u003eProduct Details\u003c\/h2\u003e\n  \u003cp\u003eThis aftermarket \u003cstrong\u003ewater pump impeller with drive key\u003c\/strong\u003e is designed to help maintain proper cooling-water circulation in compatible small outboard engines. It is listed for selected Nissan and Tohatsu 2-stroke models from 2 to 5 HP, Tohatsu MFS4–6 HP 4-stroke models, and selected Mercury\/Mariner 2–3.5 HP carbureted 4-stroke models.\u003c\/p\u003e\n  \u003cp\u003eThe impeller is supplied with the key required for installation. Confirm your exact engine model, stroke, and existing impeller dimensions before ordering.\u003c\/p\u003e\n  \u003cul\u003e\n    \u003cli\u003eSix-blade water pump impeller with included drive key.\u003c\/li\u003e\n    \u003cli\u003eDirect replacement design for compatible water pump assemblies.\u003c\/li\u003e\n    \u003cli\u003eApproximate dimensions: 10.25 mm inside diameter, 33.6 mm outside diameter, and 14.2 mm width.\u003c\/li\u003e\n    \u003cli\u003eFor cooling-system service on compatible small outboard engines.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n  \u003cp\u003eUse these manufacturer and aftermarket reference numbers to help identify the correct replacement. Numbers are provided for identification and compatibility checking.\u003c\/p\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:400px; }\n    table.ss-table th, table.ss-table td { padding:10px 12px; border:1px solid #e5e7eb; text-align:left; vertical-align:top; }\n    table.ss-table th { white-space:nowrap; word-break:normal; letter-spacing:normal; font-weight:600; background:#f8fafc; }\n    @media (max-width:480px){ table.ss-table th, table.ss-table td { padding:8px 10px; font-size:14px; } }\n  \u003c\/style\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 or Source\u003c\/th\u003e\n\u003cth\u003eReference Number\u003c\/th\u003e\n\u003c\/tr\u003e\n      \u003c\/thead\u003e\n      \u003ctbody\u003e\n        \u003ctr\u003e\n\u003ctd\u003eTohatsu\u003c\/td\u003e\n\u003ctd\u003e369-65021-1\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eTohatsu catalog reference\u003c\/td\u003e\n\u003ctd\u003e369650211M\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n\u003ctd\u003e47-16154-3\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-3098\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eMallory\u003c\/td\u003e\n\u003ctd\u003e9-45302\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eCEF\u003c\/td\u003e\n\u003ctd\u003e500377\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003c\/tbody\u003e\n    \u003c\/table\u003e\n  \u003c\/div\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eEngine \u0026amp; Model Compatibility\u003c\/h2\u003e\n  \u003cp\u003eThe applications below reflect the available product fitment records. Model, stroke, and horsepower conditions must be considered together. Do not rely on horsepower alone to confirm fitment.\u003c\/p\u003e\n  \u003ch3\u003eTohatsu and Nissan 2-Stroke Applications\u003c\/h3\u003e\n  \u003cdiv class=\"ss-table-wrap\"\u003e\n    \u003ctable class=\"ss-table\" aria-label=\"Tohatsu and Nissan 2-Stroke Compatibility\"\u003e\n      \u003cthead\u003e\n        \u003ctr\u003e\n\u003cth\u003eBrand\u003c\/th\u003e\n\u003cth\u003eModel or Description\u003c\/th\u003e\n\u003cth\u003eRated HP\u003c\/th\u003e\n\u003cth\u003eStroke\u003c\/th\u003e\n\u003cth\u003eReference\u003c\/th\u003e\n\u003c\/tr\u003e\n      \u003c\/thead\u003e\n      \u003ctbody\u003e\n        \u003ctr\u003e\n\u003ctd\u003eTohatsu\/Nissan\u003c\/td\u003e\n\u003ctd\u003e2 HP models\u003c\/td\u003e\n\u003ctd\u003e2\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e369-65021-1\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eTohatsu\/Nissan\u003c\/td\u003e\n\u003ctd\u003e2.5 HP models\u003c\/td\u003e\n\u003ctd\u003e2.5\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e369-65021-1\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eTohatsu\/Nissan\u003c\/td\u003e\n\u003ctd\u003eM2.5A, M3.5A, M3.5B and related 2.5–3.5 HP models\u003c\/td\u003e\n\u003ctd\u003e2.5–3.5\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e369-65021-1\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eTohatsu\/Nissan\u003c\/td\u003e\n\u003ctd\u003e3.5 HP models\u003c\/td\u003e\n\u003ctd\u003e3.5\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e369-65021-1\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eTohatsu\/Nissan\u003c\/td\u003e\n\u003ctd\u003e4–5 HP models\u003c\/td\u003e\n\u003ctd\u003e4–5\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e369-65021-1\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eNissan\u003c\/td\u003e\n\u003ctd\u003e3.5B \/ NS5B\u003c\/td\u003e\n\u003ctd\u003e3.5–5\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e369-65021-1\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003c\/tbody\u003e\n    \u003c\/table\u003e\n  \u003c\/div\u003e\n  \u003ch3\u003eTohatsu 4-Stroke Applications\u003c\/h3\u003e\n  \u003cdiv class=\"ss-table-wrap\"\u003e\n    \u003ctable class=\"ss-table\" aria-label=\"Tohatsu 4-Stroke 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\u003eReference\u003c\/th\u003e\n\u003c\/tr\u003e\n      \u003c\/thead\u003e\n      \u003ctbody\u003e\n        \u003ctr\u003e\n\u003ctd\u003eTohatsu\u003c\/td\u003e\n\u003ctd\u003eMFS4\u003c\/td\u003e\n\u003ctd\u003e4\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e369-65021-1\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eTohatsu\u003c\/td\u003e\n\u003ctd\u003eMFS5\u003c\/td\u003e\n\u003ctd\u003e5\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e369-65021-1\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eTohatsu\u003c\/td\u003e\n\u003ctd\u003eMFS6\u003c\/td\u003e\n\u003ctd\u003e6\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e369-65021-1\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003c\/tbody\u003e\n    \u003c\/table\u003e\n  \u003c\/div\u003e\n  \u003ch3\u003eMercury\/Mariner 4-Stroke Applications\u003c\/h3\u003e\n  \u003cdiv class=\"ss-table-wrap\"\u003e\n    \u003ctable class=\"ss-table\" aria-label=\"Mercury Mariner 4-Stroke Compatibility\"\u003e\n      \u003cthead\u003e\n        \u003ctr\u003e\n\u003cth\u003eBrand\u003c\/th\u003e\n\u003cth\u003eModel or Description\u003c\/th\u003e\n\u003cth\u003eRated HP\u003c\/th\u003e\n\u003cth\u003eStroke\u003c\/th\u003e\n\u003cth\u003eCondition\u003c\/th\u003e\n\u003cth\u003eReference\u003c\/th\u003e\n\u003c\/tr\u003e\n      \u003c\/thead\u003e\n      \u003ctbody\u003e\n        \u003ctr\u003e\n\u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n\u003ctd\u003e2 HP\u003c\/td\u003e\n\u003ctd\u003e2\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003eCarbureted models\u003c\/td\u003e\n\u003ctd\u003e47-16154-3\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n\u003ctd\u003e2.5 HP\u003c\/td\u003e\n\u003ctd\u003e2.5\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003eCarbureted models\u003c\/td\u003e\n\u003ctd\u003e47-16154-3\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n\u003ctd\u003e3.5 HP\u003c\/td\u003e\n\u003ctd\u003e3.5\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003eCarbureted models\u003c\/td\u003e\n\u003ctd\u003e47-16154-3\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003c\/tbody\u003e\n    \u003c\/table\u003e\n  \u003c\/div\u003e\n  \u003cp\u003e\u003cstrong\u003eFitment note:\u003c\/strong\u003e The compatibility records do not establish universal fitment across every engine in the same horsepower range. Check the full model designation and compare the original impeller dimensions before installation.\u003c\/p\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eTechnical Specs\u003c\/h2\u003e\n  \u003cdl\u003e\n    \u003cdt\u003eProduct Type\u003c\/dt\u003e\n    \u003cdd\u003eWater pump impeller with drive key\u003c\/dd\u003e\n    \u003cdt\u003eApplication\u003c\/dt\u003e\n    \u003cdd\u003eCooling-system replacement for compatible small outboard engines\u003c\/dd\u003e\n    \u003cdt\u003eNumber of Blades\u003c\/dt\u003e\n    \u003cdd\u003e6\u003c\/dd\u003e\n    \u003cdt\u003eInside Diameter\u003c\/dt\u003e\n    \u003cdd\u003e10.25 mm\u003c\/dd\u003e\n    \u003cdt\u003eOutside Diameter\u003c\/dt\u003e\n    \u003cdd\u003e33.6 mm\u003c\/dd\u003e\n    \u003cdt\u003eWidth\u003c\/dt\u003e\n    \u003cdd\u003e14.2 mm\u003c\/dd\u003e\n    \u003cdt\u003eInstallation\u003c\/dt\u003e\n    \u003cdd\u003eDirect replacement in a matching water pump assembly\u003c\/dd\u003e\n  \u003c\/dl\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eWhat's in the Box\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003e1 x Six-blade water pump impeller\u003c\/li\u003e\n    \u003cli\u003e1 x Drive key\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n  \u003col\u003e\n    \u003cli\u003eDisconnect the battery and remove the spark plug wire or wires before servicing the outboard.\u003c\/li\u003e\n    \u003cli\u003ePlace the engine in neutral and remove the fasteners securing the lower unit or gearcase.\u003c\/li\u003e\n    \u003cli\u003eSeparate the lower unit carefully, paying attention to the shift shaft and driveshaft alignment.\u003c\/li\u003e\n    \u003cli\u003eRemove the water pump housing cover and take out the old impeller and drive key.\u003c\/li\u003e\n    \u003cli\u003eClean debris from the housing and inspect the housing, wear plate, seals, and keyway for damage or excessive wear.\u003c\/li\u003e\n    \u003cli\u003eInstall the supplied key and impeller in the correct orientation. Use a suitable water-pump lubricant during assembly and rotate the driveshaft in the normal direction of operation as the impeller enters the housing.\u003c\/li\u003e\n    \u003cli\u003eReinstall the housing and any removed gaskets or seals according to the engine manufacturer's service procedure.\u003c\/li\u003e\n    \u003cli\u003eReassemble the lower unit and test the cooling-water flow using an appropriate water supply before returning the engine to service.\u003c\/li\u003e\n  \u003c\/ol\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow do I know if my impeller is failing?\u003c\/summary\u003e\n    \u003cp\u003eCommon warning signs include weak or missing water flow from the tell-tale outlet, overheating, an overheat alarm, or visible cracks, deformation, or missing blades during inspection.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eDoes this product include the drive key?\u003c\/summary\u003e\n    \u003cp\u003eYes. This listing is for a water pump impeller supplied with a drive key. Confirm that the keyway and impeller dimensions match your original components before installation.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWill this fit any 2–6 HP outboard?\u003c\/summary\u003e\n    \u003cp\u003eNo. Horsepower by itself does not confirm fitment. This product is listed for the specific Tohatsu, Nissan, and Mercury\/Mariner model groups shown above. Check the exact model, stroke type, and dimensions before ordering.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat is the difference between this impeller and the OEM version?\u003c\/summary\u003e\n    \u003cp\u003eThis is an aftermarket replacement impeller, not an original manufacturer-supplied component. It is intended for applications using the listed reference numbers and matching dimensions.\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 as part of regular maintenance and replace it when the blades show wear, cracking, distortion, or damage. Follow the service interval recommended for your specific engine and operating conditions.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eSafety \u0026amp; Important Information\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eVerify the exact engine model, stroke type, reference number, and dimensions before purchase.\u003c\/li\u003e\n    \u003cli\u003eAll brand names and reference numbers are used only to identify compatible applications; this product is aftermarket and is not an OEM component.\u003c\/li\u003e\n    \u003cli\u003eDo not operate an outboard with inadequate cooling-water flow. Stop the engine immediately if overheating or a loss of tell-tale flow occurs.\u003c\/li\u003e\n    \u003cli\u003eProfessional installation is recommended when you are not familiar with lower-unit or water-pump service.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n  \u003cp\u003eSea Sierra supplies aftermarket marine replacement parts for maintenance and repair applications. Product compatibility should always be confirmed against the engine's exact model information and the original part before installation.\u003c\/p\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50723807887675,"sku":"17IT001-K","price":16.28,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/Water_Pump_Impeller_for_Tohatsu_Nissan_25-6_HP_18-3098_-_JLM_MARINE-8288311.jpg?v=1763032297"}],"url":"https:\/\/seasierra.com\/collections\/tohatsu-4-stroke-2-5-6hp-outboard-marine-engine-parts.oembed","provider":"SeaSierra","version":"1.0","type":"link"}