{"title":"Mercury 2-Stroke Outboard Engine 4-9.9HP Parts","description":"\u003csection id=\"hero\" style=\"padding:16px; border:1px solid #e5e7eb; border-radius:8px;\"\u003e\n  \u003cp\u003eThis page focuses on Mercury 2‑Stroke 4–9.9HP outboard engines. Use it to find compatible parts and practical service information, including maintenance tips, frequently replaced items, and troubleshooting guidance. You can also browse the main Mercury collection at any time. Scroll to the bottom of this 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\/mercury-outboard-parts\" style=\"display:inline-block; margin-top:8px; padding:10px 14px; background:#0f766e; color:#fff; text-decoration:none; border-radius:6px;\"\u003eBrowse All Mercury Parts\u003c\/a\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"identify-model\" style=\"padding:16px;\"\u003e\n  \u003ch2\u003eHow to Identify Your 4–9.9HP Model\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eNameplate location: Look for the serial plate on the transom clamp bracket or swivel bracket. The serial number is the primary reference for Mercury parts.\u003c\/li\u003e\n    \u003cli\u003eDecoding details: Suffix letters commonly indicate shaft length (S ≈ 15 in, L ≈ 20 in) and equipment (tiller\/remote, manual\/electric start). These affect cables, wiring, and gearcase\/prop selections.\u003c\/li\u003e\n    \u003cli\u003ePlatform clues: Many 4–6HP 2‑strokes are single‑cylinder; 7.5–9.9HP models are typically twin‑cylinder. Cylinder count helps confirm plug type, carb size, and prop fit.\u003c\/li\u003e\n    \u003cli\u003e2‑Stroke confirmation: Cowl decals or a fuel‑mix sticker usually indicate 2‑stroke. Most small Mercury 2‑strokes use premix fuel unless clearly oil‑injected—check your cowl label\/manual.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"engine-overview\" style=\"padding:16px;\"\u003e\n  \u003ch2\u003ePlatform Overview\u003c\/h2\u003e\n  \u003ch3\u003eSingle‑Cylinder 2‑Stroke (Approx. 4–6HP)\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 #f1f5f9;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eCarbureted single‑cylinder 2‑stroke, tiller steer, manual or electric start.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eMercury 4\/5\/6HP 2‑Stroke variants (short or long shaft).\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eVery light and portable; simple maintenance; easy to stow for dinghy\/tender use.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eConfirm shaft length and prop spline\/diameter. Impeller and carb parts may vary by serial number break.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\n  \u003ch3\u003eTwin‑Cylinder 2‑Stroke (Approx. 7.5–9.9HP)\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 #f1f5f9;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eCarbureted twin‑cylinder 2‑stroke; available in 15\" or 20\" shafts; tiller or remote.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eMercury 7.5\/8\/9.8\/9.9HP 2‑Stroke models.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eStronger thrust and mid‑range torque; common service parts; broad propeller choices.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eMany parts interchange within serial ranges, but verify by serial number for impellers, gear seals, and ignition components.\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=\"padding:16px;\"\u003e\n  \u003ch2\u003eRoutine Maintenance \u0026amp; Service Parts\u003c\/h2\u003e\n  \u003cp\u003eIntervals below are general guidelines for small 2‑stroke outboards. Always follow the official service manual for your exact serial number and model.\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 #f1f5f9;\"\u003eGear oil (lower unit)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eEvery 100 hrs or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eCheck for water\/milkiness; replace seals if contamination is found.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/service-maintenance-kits\"\u003eService \u0026amp; Maintenance Kits\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eSpark plugs\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eInspect each 50–100 hrs; replace annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eGap and heat range vary by cylinder count and serial range.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/spark-plug\"\u003eSpark plug\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eInline fuel filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eEvery 100 hrs or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eReplace sooner if debris or stale fuel is suspected.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\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 #f1f5f9;\"\u003eWater pump impeller\/kit\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eEvery 2 seasons (or 200 hrs)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eReplace annually for heavy sand\/silt usage or weak tell‑tale stream.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-water-pump-repair-kits\"\u003eMercury 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 #f1f5f9;\"\u003eAnodes (zincs)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eInspect each season; replace at ~50% loss\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eChoose material for your water (zinc\/brackish, aluminum\/salt, magnesium\/fresh).\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/anodes\"\u003eAnodes\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eFuel\/oil mix (2‑stroke)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eEvery fill‑up\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eMost small Mercury 2‑strokes run 50:1 TC‑W3 oil—verify cowl label\/manual.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-outboard-parts\"\u003eMercury Outboard Parts\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eCarburetor service (gaskets\/diaphragms)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eAs needed (stale fuel\/rough idle)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eClean jets, replace gaskets; confirm primer\/choke function.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/carburetor\"\u003eCarburetor\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eLower unit seal kit (if water in oil)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eWhen contamination is found\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eAddress driveshaft\/prop shaft\/carrier seals after pressure\/vac tests.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-lower-unit-seal-kits\"\u003eMercury Lower Unit Seal Kits\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=\"padding:16px;\"\u003e\n  \u003ch2\u003eFrequently Used Parts Categories\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eRoutine Service: \u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-outboard-parts\"\u003eMercury Outboard Parts\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCooling System: \u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-water-pump-repair-kits\"\u003eMercury Water Pump Repair Kits\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eFuel System (filters): \u003ca href=\"https:\/\/seasierra.com\/collections\/fuel-filters-1\"\u003eFuel Filters\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCarburetion: \u003ca href=\"https:\/\/seasierra.com\/collections\/carburetor\"\u003eCarburetor\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\u003eCorrosion Protection: \u003ca href=\"https:\/\/seasierra.com\/collections\/anodes\"\u003eAnodes\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  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"troubleshooting\" style=\"padding:16px;\"\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 #f1f5f9;\"\u003eWeak tell‑tale stream or overheat alarm\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eIntake screen for blockage; impeller wear; thermostat stuck; kinked tell‑tale hose.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eWater pump kit, thermostat, intake screen, grommets\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003ePoor acceleration or power loss\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eProp damage\/cavitation; fouled plugs; fuel restriction; carb jets dirty; timing linkages.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003ePropeller, spark plugs, fuel filter, carb gaskets\/kit\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eHard starting or rough idle\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eStale fuel; primer bulb leaks; choke\/primer operation; vacuum leaks at carb base.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eFuel filter, primer bulb\/hose, carb kit, intake gaskets, spark plugs\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eExcessive smoke\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eOil ratio too rich; choke stuck; extended idling; low‑temp operation.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f1f5f9;\"\u003eSpark plugs, carb gaskets\/kit, thermostat\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eGearcase noise or metal in gear oil\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eCheck oil level\/condition; pressure\/vacuum test; inspect prop shaft for fishing line.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eLower unit seal kit, bearings, shims, gear oil\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=\"padding:16px;\"\u003e\n  \u003ch2\u003eFAQs\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eAre parts interchangeable across different years or serial ranges?\u003c\/summary\u003e\n    \u003cp\u003eMany small Mercury 2‑stroke parts interchange within defined serial ranges, but changes in impeller, ignition, and carburetor components are common. Always confirm by serial number, shaft length, and start type (manual\/electric).\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\u003eAs a rule of thumb, replace every 2 seasons (or ~200 hours). Shorten the interval if you boat in sand\/silt, run aground, or notice a weak tell‑tale stream or overheat symptoms.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow often should I change the lower unit gear oil?\u003c\/summary\u003e\n    \u003cp\u003eAt least once per season or every 100 hours. Inspect for water contamination (milky color); if present, service seals and retest before returning to service.\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\u003eProvide the engine serial number from the transom clamp bracket, shaft length (15\" S or 20\" L), steering\/control type (tiller or remote), and whether it is manual or electric start. Photos of the nameplate and the part area help verify fit.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"cta\" style=\"padding:16px; border-top:1px solid #e5e7eb;\"\u003e\n  \u003cp\u003eReady to find what you need? Browse the main Mercury collection and filter by horsepower, year, and model to zero in on the right parts.\u003c\/p\u003e\n  \u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-outboard-parts\" style=\"display:inline-block; margin:8px 0; padding:10px 14px; background:#0f766e; color:#fff; text-decoration:none; border-radius:6px;\"\u003eShop Mercury Outboard Parts\u003c\/a\u003e\n  \u003cp style=\"font-size:0.9em; color:#334155;\"\u003eIf you’re unsure about your model, send us a clear photo of the nameplate and the part you need—our team will help verify compatibility.\u003c\/p\u003e\n\u003c\/section\u003e","products":[{"product_id":"inline-fuel-filter-fits-yamaha-4-9-9-hp-replaces-646-24251-01-00-646-24251-02-00","title":"Inline Fuel Filter – Fits Yamaha 115–250 HP 2-Stroke Outboards (Replaces 646-24251-01, 646-24251-00, 646-24251-02, 6R5-24251-02)","description":"\u003csection\u003e\n\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\u003einline fuel filter\u003c\/strong\u003e is designed for selected Yamaha 2-stroke outboards from 115 through 250 HP. It helps remove contaminants from the fuel system before fuel reaches the engine. The company-listed Yamaha applications include V4 and V6 models covering 115, 130, 140, 150–200, 225, and 250 HP, with model-specific year ranges shown below.\u003c\/p\u003e\n\u003cp\u003eThe filter is identified by aftermarket reference \u003cstrong\u003e18-7713\u003c\/strong\u003e. Listed Yamaha replacement references are \u003cstrong\u003e646-24251-01\u003c\/strong\u003e, \u003cstrong\u003e646-24251-00\u003c\/strong\u003e, \u003cstrong\u003e646-24251-02\u003c\/strong\u003e, and \u003cstrong\u003e6R5-24251-02\u003c\/strong\u003e. The same aftermarket reference is also listed against Mercury\/Mariner reference \u003cstrong\u003e35-80365M\u003c\/strong\u003e; confirm the engine model and serial-number conditions before ordering.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eInline fuel-filter design for installation in the fuel line.\u003c\/li\u003e\n  \u003cli\u003eTranslucent housing helps with visual inspection of fuel and visible contamination.\u003c\/li\u003e\n  \u003cli\u003eDirectional flow arrow should point toward the engine fuel pump.\u003c\/li\u003e\n  \u003cli\u003eSold as one individual fuel filter; no additional fittings or installation hardware are included.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n\u003cp\u003eUse the references below to compare the filter with the part being replaced. Part-number references are not a substitute for checking the complete engine model, year, and serial-number conditions.\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\u003e646-24251-01\u003c\/td\u003e\n\u003ctd\u003eListed replacement reference\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e646-24251-00\u003c\/td\u003e\n\u003ctd\u003eListed replacement reference\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e646-24251-02\u003c\/td\u003e\n\u003ctd\u003eListed replacement reference\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003e6R5-24251-02\u003c\/td\u003e\n\u003ctd\u003eListed replacement reference\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n\u003ctd\u003e35-80365M\u003c\/td\u003e\n\u003ctd\u003eListed replacement\/reference number\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eAftermarket\u003c\/td\u003e\n\u003ctd\u003e18-7713\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 Yamaha applications below are the company-listed fitment for this product. Keep the horsepower, stroke, model family, and year range together when checking compatibility.\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\u003eModel\/Application\u003c\/th\u003e\n\u003cth\u003eRated HP\u003c\/th\u003e\n\u003cth\u003eStroke\u003c\/th\u003e\n\u003cth\u003eYears\u003c\/th\u003e\n\u003cth\u003eListed References\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\u003eV4 models\u003c\/td\u003e\n\u003ctd\u003e115\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1984–2014\u003c\/td\u003e\n\u003ctd\u003e646-24251-01, 646-24251-00, 646-24251-02, 6R5-24251-02\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eV4 models\u003c\/td\u003e\n\u003ctd\u003e130\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1988–2014\u003c\/td\u003e\n\u003ctd\u003e646-24251-01, 646-24251-00, 646-24251-02, 6R5-24251-02\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eV4 models\u003c\/td\u003e\n\u003ctd\u003e140\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1989–2005\u003c\/td\u003e\n\u003ctd\u003e646-24251-01, 646-24251-00, 646-24251-02, 6R5-24251-02\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eV6 models\u003c\/td\u003e\n\u003ctd\u003e150–200\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1984–2013\u003c\/td\u003e\n\u003ctd\u003e646-24251-01, 646-24251-00, 646-24251-02, 6R5-24251-02\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eV6 models\u003c\/td\u003e\n\u003ctd\u003e225\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1984–2004\u003c\/td\u003e\n\u003ctd\u003e646-24251-01, 646-24251-00, 646-24251-02, 6R5-24251-02\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eV6 models\u003c\/td\u003e\n\u003ctd\u003e250\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1992–2003\u003c\/td\u003e\n\u003ctd\u003e646-24251-01, 646-24251-00, 646-24251-02, 6R5-24251-02\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch3\u003eAdditional Mercury\/Mariner Reference\u003c\/h3\u003e\n\u003cp\u003eCatalog records associate reference \u003cstrong\u003e35-80365M\u003c\/strong\u003e with selected Mercury 4-stroke fuel-pump applications, including 8 HP, 9.9 HP, and 15 HP models. These records include serial-number-specific ranges such as 0H017100–0H017265, 0H000058 and up, 0P086824–0P400999, 0H000058–0H016909, 0G760300–1B226999, 0P075166–0P400999, 0P134638–0P400999, 0G590000–0G760299, and 9973100–0P016999. Because the applicable model, diagram position, and serial range vary, verify all conditions against the engine before installation.\u003c\/p\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003cdl\u003e\n  \u003cdt\u003eProduct Type\u003c\/dt\u003e\n\u003cdd\u003eInline fuel filter\u003c\/dd\u003e\n  \u003cdt\u003eApplication\u003c\/dt\u003e\n\u003cdd\u003eSelected marine outboard fuel systems\u003c\/dd\u003e\n  \u003cdt\u003ePrimary Listed Fitment\u003c\/dt\u003e\n\u003cdd\u003eYamaha 115–250 HP 2-stroke V4 and V6 outboards\u003c\/dd\u003e\n  \u003cdt\u003eInstallation\u003c\/dt\u003e\n\u003cdd\u003eInline in the fuel line\u003c\/dd\u003e\n  \u003cdt\u003eFuel Type\u003c\/dt\u003e\n\u003cdd\u003eGasoline\u003c\/dd\u003e\n  \u003cdt\u003eHousing\u003c\/dt\u003e\n\u003cdd\u003eTranslucent filter housing\u003c\/dd\u003e\n  \u003cdt\u003eConnection\u003c\/dt\u003e\n\u003cdd\u003eInline hose connection\u003c\/dd\u003e\n  \u003cdt\u003eFlow Direction\u003c\/dt\u003e\n\u003cdd\u003eDirectional; arrow must point toward the fuel pump\u003c\/dd\u003e\n  \u003cdt\u003eThreaded Connection\u003c\/dt\u003e\n\u003cdd\u003eNot applicable; inline hose connection\u003c\/dd\u003e\n  \u003cdt\u003eProduct Status\u003c\/dt\u003e\n\u003cdd\u003eAftermarket replacement 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 Inline fuel filter\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n  \u003cli\u003eTurn the engine off and allow it to cool before beginning work.\u003c\/li\u003e\n  \u003cli\u003eWork in a well-ventilated area away from flames, sparks, and other ignition sources.\u003c\/li\u003e\n  \u003cli\u003eLocate the existing filter and note the direction of its flow arrow.\u003c\/li\u003e\n  \u003cli\u003ePlace an absorbent rag beneath the filter and carefully disconnect the fuel line. Clamp or cap the hose as appropriate to limit fuel spillage.\u003c\/li\u003e\n  \u003cli\u003eRemove the old filter and inspect the hose ends and clamps. Replace damaged or deteriorated hose or clamps before installation.\u003c\/li\u003e\n  \u003cli\u003eInstall the replacement filter with its arrow pointing away from the fuel tank and toward the engine fuel pump.\u003c\/li\u003e\n  \u003cli\u003eSecure both fuel-line connections and check that the hoses are fully seated.\u003c\/li\u003e\n  \u003cli\u003ePrime the fuel system as required by the engine manufacturer, then inspect all connections for leaks before operating the engine.\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 filter fits my engine?\u003c\/summary\u003e\n  \u003cp\u003eFirst compare the old filter's manufacturer reference with the references listed above. Then verify the complete engine brand, horsepower, model family, stroke, year, and—where applicable—serial number. Do not rely on horsepower alone.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eIs this product a kit?\u003c\/summary\u003e\n  \u003cp\u003eNo. This listing is for one individual inline fuel filter. Fuel hose, clamps, fittings, and other installation parts are not included unless separately specified.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhich way should the filter be installed?\u003c\/summary\u003e\n  \u003cp\u003eInstall the filter so the arrow on the housing points in the direction of fuel flow, from the tank toward the engine fuel pump.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat are common signs of a restricted fuel filter?\u003c\/summary\u003e\n  \u003cp\u003ePossible symptoms include difficult starting, hesitation, sputtering, reduced power, or stalling under load. Visible debris or discoloration in a translucent housing can also indicate that inspection or replacement is needed.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eCan I use this filter on a different engine because the part looks similar?\u003c\/summary\u003e\n  \u003cp\u003eNo. Similar appearance does not establish compatibility. Confirm the listed part reference and all engine fitment conditions before installation.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eIs this an OEM filter?\u003c\/summary\u003e\n  \u003cp\u003eThis is an aftermarket replacement filter. Yamaha, Mercury, Mariner, and other brand names and part numbers are used only to identify referenced applications and replacement references.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhen should the filter be replaced?\u003c\/summary\u003e\n  \u003cp\u003eInspect and replace the filter according to the engine manufacturer's service schedule and whenever contamination, restricted fuel flow, damage, or a leak is found.\u003c\/p\u003e\n\u003c\/details\u003e\n\n\u003ch2\u003eSafety \u0026amp; Important Information\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eFuel is flammable. Shut down the engine and eliminate ignition sources before servicing the fuel system.\u003c\/li\u003e\n  \u003cli\u003eCheck every connection for leaks before starting or operating the engine.\u003c\/li\u003e\n  \u003cli\u003eConfirm the part number and complete engine fitment conditions before purchase.\u003c\/li\u003e\n  \u003cli\u003eProfessional installation is recommended if you are not experienced with marine fuel-system service.\u003c\/li\u003e\n  \u003cli\u003eThis is an aftermarket replacement component, not an original-equipment component.\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 Parts Focus\u003c\/strong\u003e — Replacement components for outboard and marine fuel systems.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFitment-Focused Listings\u003c\/strong\u003e — Product references and application details are provided to support part-number matching.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eReplacement Value\u003c\/strong\u003e — Practical aftermarket alternatives for routine marine maintenance.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50723978314043,"sku":"23FF039","price":18.46,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/Inline_Fuel_Filter_for_Yamaha_4-99_HP_646-24251-01-00_-_JLM_MARINE-8286040.png?v=1763039112"}],"url":"https:\/\/seasierra.com\/collections\/mercury-2-stroke-outboard-engine-4-9-9hp-parts.oembed","provider":"SeaSierra","version":"1.0","type":"link"}