{"title":"Yamaha 2-Stroke Outboard Marine Engine Parts","description":"\u003csection id=\"hero\" style=\"max-width:1000px;margin:0 auto;padding:16px 12px;\"\u003e\n  \u003cp\u003eThis page is for Yamaha 2‑Stroke outboard engines. Use it to find compatible parts and service information, including maintenance tips, common replacement parts, and troubleshooting guidance. You can also browse the main Yamaha collection for a wider selection. Scroll to the bottom of this page to start browsing parts for this engine, and on the collection page use the Filter \u0026amp; Sort controls to narrow results by horsepower, year range, and part category\/section.\u003c\/p\u003e\n  \u003cp\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-outboard-parts\" style=\"display:inline-block;background:#0a4;color:#fff;padding:10px 14px;border-radius:6px;text-decoration:none;\"\u003eBrowse All Yamaha Parts\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"identify-model\" style=\"max-width:1000px;margin:0 auto;padding:16px 12px;\"\u003e\n  \u003ch2\u003eHow to Identify Your Yamaha 2‑Stroke Model\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eNameplate location: Look for the model\/serial plate on the transom clamp bracket or the swivel bracket. It includes the model code, shaft length, and serial number.\u003c\/li\u003e\n    \u003cli\u003eReading the code: Numbers indicate horsepower; suffix letters note features. Common letters: S=15\" shaft, L=20\", X=25\", U=30\"; R=remote controls, H=tiller; E=electric start, M=manual start; T=power trim \u0026amp; tilt, P=power tilt.\u003c\/li\u003e\n    \u003cli\u003ePlatform clues: 2‑Stroke models range from small carbureted twins\/triples to larger V4\/V6, including EFI (OX66) and HPDI variants. Oil‑injected models have an engine\/remote oil tank; some portables are premix.\u003c\/li\u003e\n    \u003cli\u003eFor parts accuracy: Confirm horsepower, full model code, shaft length, and serial prefix before ordering.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"engine-overview\" style=\"max-width:1000px;margin:0 auto;padding:16px 12px;\"\u003e\n  \u003ch2\u003ePlatform Overview\u003c\/h2\u003e\n  \u003ch3\u003ePortable \u0026amp; Midrange 2‑Stroke (approx. 2–90 HP)\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 #ccc;padding:8px;\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;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 #eee;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eInline 1–3 cylinder, carbureted 2‑Stroke; manual or electric start; tiller or remote controls.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eTypical 25\/40\/50\/70\/90 HP 2‑Stroke models (various shaft lengths and control options).\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eLight weight, simple maintenance, excellent power‑to‑weight, easy service access.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eConfirm premix vs. oil‑injection. Many parts vary by shaft length, control type, and year code.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\n  \u003ch3\u003eHigh‑Output 2‑Stroke (approx. 115–250 HP)\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 #ccc;padding:8px;\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;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 #eee;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eV4\/V6 2‑Stroke, including carbureted, OX66 EFI, and HPDI fuel systems.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003e115\/130 (V4) and 150\/175\/200\/225\/250 (V6), including performance series like VMAX.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eStrong hole‑shot and mid‑range torque; proven durability for offshore and bass applications.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eFuel and ignition parts differ by injection type. Verify model code, year letter, and gearcase style before ordering.\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:1000px;margin:0 auto;padding:16px 12px;\"\u003e\n  \u003ch2\u003eRoutine Maintenance \u0026amp; Service Parts\u003c\/h2\u003e\n  \u003cp\u003eIntervals below are general guidelines for typical Yamaha 2‑Stroke use. Always follow the procedures and schedules in your engine’s official service manual.\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 #ccc;padding:8px;\"\u003eItem\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;padding:8px;\"\u003eInterval*\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;padding:8px;\"\u003eRemarks\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;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 #eee;\"\u003eGear oil (lower unit)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003e100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eInspect for metal or water; replace sealing washers; check for leaks.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\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:8px;border-bottom:1px solid #eee;\"\u003eSpark plugs\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003e100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eCheck condition and gap; replace if fouled or worn.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\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 #eee;\"\u003eFuel filter \/ in‑line filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003e100 hours or each season\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eReplace if contaminated; drain water separators regularly.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\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 #eee;\"\u003eWater pump impeller \/ kit\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003e2–3 years or 200 hours\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eReplace sooner if weak tell‑tale or overheat occurs; inspect housing and wear plate.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\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:8px;border-bottom:1px solid #eee;\"\u003eAnodes (external \u0026amp; internal)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eInspect often; replace at ~50% loss\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eChoose material for your water type; ensure good metal‑to‑metal contact.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\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:8px;border-bottom:1px solid #eee;\"\u003eOil injection system service (if equipped)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eAnnually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eInspect tanks\/lines, strainers and filters; test alarms; bleed system per manual.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\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:8px;border-bottom:1px solid #eee;\"\u003ePropeller \u0026amp; hub inspection\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eEach trip; remove seasonally\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eCheck for dings and line on the shaft; grease splines; verify pitch for target RPM.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-propellers\"\u003eYamaha Propellers\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eLower unit seal replacement (as needed)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eOn water intrusion or during rebuild\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eReplace propshaft\/driveshaft\/input seals and O‑rings; pressure test after assembly.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\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:8px;border-bottom:1px solid #eee;\"\u003eFuel\/oil mix (premix models)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eEvery refuel\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eUse the ratio specified in your manual (commonly 50:1 TC‑W3); do not premix on oil‑injected engines.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-outboard-parts\"\u003eYamaha Outboard Parts\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:#555;\"\u003e*Intervals are general references. Always follow your Yamaha service manual and adjust for duty cycle and environment.\u003c\/p\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"common-parts\" style=\"max-width:1000px;margin:0 auto;padding:16px 12px;\"\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\u003ePropellers \u0026amp; Hubs: \u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-propellers\"\u003eYamaha Propellers\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eIgnition \/ Starting: \u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-starters\"\u003eYamaha Starters\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eGaskets \u0026amp; Sealing: \u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-gaskets\"\u003eYamaha Gaskets\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  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"troubleshooting\" style=\"max-width:1000px;margin:0 auto;padding:16px 12px;\"\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 #ccc;padding:8px;\"\u003eSymptom\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;padding:8px;\"\u003eCheck First\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;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 #eee;\"\u003eWeak tell‑tale or overheat alarm\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eInspect intake screens for blockage; verify thermostat operation; check impeller condition and key.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eWater pump kit, thermostat, intake screen, gaskets\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003ePoor acceleration \/ power loss\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eConfirm prop condition and pitch; drain stale fuel; replace clogged fuel filter; inspect plugs and timing.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003ePropeller, fuel filter, spark plugs, gasket sets\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eHard starting \/ rough idle\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003ePrime fuel system; check for air leaks at connectors\/hoses; clean idle circuits; verify choke\/enrichment.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eFuel connectors, hoses, spark plugs, carb gaskets\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eExcessive smoke (2‑Stroke)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eVerify premix ratio or oil‑pump setting; check thermostat (cold running increases smoke); confirm plug heat range.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eSpark plugs, thermostat, oil‑injection components\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eGearcase noise \/ metal in gear oil\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eCheck oil level\/condition; inspect for fishing line on propshaft; pressure\/vacuum test seals and bearings.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #eee;\"\u003eLower unit seal kit, bearings, prop shaft seal\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:1000px;margin:0 auto;padding:16px 12px;\"\u003e\n  \u003ch2\u003eFAQs\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eAre Yamaha 2‑Stroke parts interchangeable across years and platforms?\u003c\/summary\u003e\n    \u003cp\u003eMany fasteners and service items are shared, but key components (cooling, fuel, ignition, gearcase, and controls) often change by model year, shaft length, and fuel‑system type (carbureted vs. EFI\/HPDI). Always match parts using the full model code and serial.\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 preventative maintenance, replace every 2–3 seasons or ~200 hours, and sooner if you see a weak tell‑tale, overheat, or sand\/silt use. Inspect the housing and wear plate and renew as needed.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow often should I change lower unit gear oil?\u003c\/summary\u003e\n    \u003cp\u003eChange at least annually or every 100 hours. Inspect the drained oil for milkiness (water) or metallic debris. If contamination is present, service seals and pressure‑test the gearcase.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat information helps confirm part compatibility?\u003c\/summary\u003e\n    \u003cp\u003eProvide the full model code, serial number, horsepower, shaft length, control type (tiller\/remote), and a clear photo of the nameplate. For fuel‑injected models, note OX66 or HPDI where applicable.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"cta\" style=\"max-width:1000px;margin:0 auto;padding:16px 12px;\"\u003e\n  \u003cp\u003eReady to find the right components? Browse the main Yamaha collection and filter by horsepower, year, and model to locate the parts you need.\u003c\/p\u003e\n  \u003cp\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/yamaha-outboard-parts\" style=\"display:inline-block;background:#0a4;color:#fff;padding:10px 14px;border-radius:6px;text-decoration:none;\"\u003eShop Yamaha Outboard Parts\u003c\/a\u003e\u003c\/p\u003e\n  \u003cp style=\"font-size:12px;color:#555;\"\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":"thermostat-fits-johnson-evinrude-6-250-hp-v4-v6-replaces-johnson-evinrude-5005440-434841","title":"143°F Marine Outboard Thermostat – Fits Mercury Mariner 135–200 HP EFI and Select Johnson\/Evinrude Models","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 replacement \u003cstrong\u003e143°F (62°C) marine thermostat\u003c\/strong\u003e is a single thermostat for selected Mercury\/Mariner and Johnson\/Evinrude outboard applications. The company fitment data identifies Mercury\/Mariner 135–200 HP EFI applications and additional Johnson\/Evinrude applications including 40–250 HP E-TEC, 6–55 HP, crossflow V4 and V6 models, and 9.9 HP and 15 HP four-stroke models from 1994–2001.\u003c\/p\u003e\n  \u003cp\u003eFor Mercury\/Mariner applications, the company records also list selected models and serial ranges from 7.5 HP through V300\/3.4L, including 7.5 HP serial 5226935 and up, 9.8 HP serial 5206550 and up, 40 HP serial 3336258–C159199, 50\/60 HP serial D000750 and up, 65 HP serial 3547987–4571651, 70 HP serial 4571652–4825248, 70\/75\/80\/90 HP serial A996142 and up, 100\/115 HP serial B209468 and up, V135\/V150 serial A904646 and up, V175 serial C100861 and up, V200 serial 6435503 and up, V220 serial B117316 and up, V225 serial 5628028 and up, V300\/3.4L serial 5611648 and up, and XR4 and Magnum II serial C239553–D081999. Confirm your exact model, serial number, and thermostat reference before ordering.\u003c\/p\u003e\n  \u003cul\u003e\n    \u003cli\u003eSingle aftermarket thermostat for selected marine outboard cooling systems.\u003c\/li\u003e\n    \u003cli\u003e143°F (62°C) operating temperature rating.\u003c\/li\u003e\n    \u003cli\u003eDesigned as a direct replacement when the listed reference and fitment conditions match.\u003c\/li\u003e\n    \u003cli\u003eAftermarket replacement; not an OEM-branded component.\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 the following references to compare your existing thermostat. A reference-number match should be confirmed against the complete engine model 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 or source\u003c\/th\u003e\n\u003cth\u003eReference numbers\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\u003e62981 \/ 66850 \/ 75692 \/ 75692B2 \/ 75692Q2 \/ 75692T\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eJohnson\/Evinrude\/OMC\u003c\/td\u003e\n\u003ctd\u003e377148 \/ 378065 \/ 393659 \/ 434841 \/ 437414 \/ 5005440 \/ 508626\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-3543 \/ 18-3553\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eGLM\u003c\/td\u003e\n\u003ctd\u003e13010\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eOther listed aftermarket reference\u003c\/td\u003e\n\u003ctd\u003e9-43019 \/ 9-43101\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\u003eCompatibility is application-specific. Keep horsepower, engine family, stroke type, model, and serial-number conditions together when checking 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\u003eApplication\u003c\/th\u003e\n\u003cth\u003eRated HP\u003c\/th\u003e\n\u003cth\u003eStroke or engine type\u003c\/th\u003e\n\u003cth\u003eYear or serial condition\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\u003eEFI outboard applications\u003c\/td\u003e\n\u003ctd\u003e135–200\u003c\/td\u003e\n\u003ctd\u003eVerify engine type\u003c\/td\u003e\n\u003ctd\u003eVerify model and serial number\u003c\/td\u003e\n\u003ctd\u003e62981, 66850, 75692 family\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n\u003ctd\u003eSelected small and mid-range applications\u003c\/td\u003e\n\u003ctd\u003e7.5–115\u003c\/td\u003e\n\u003ctd\u003eVerify engine type\u003c\/td\u003e\n\u003ctd\u003eSpecific serial ranges listed by the manufacturer; confirm before purchase\u003c\/td\u003e\n\u003ctd\u003e75692 family\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n\u003ctd\u003eV135, V150, V175, V200, V220, V225, V300\/3.4L\u003c\/td\u003e\n\u003ctd\u003e135–300\u003c\/td\u003e\n\u003ctd\u003eV-engine applications\u003c\/td\u003e\n\u003ctd\u003eSpecific model and serial ranges listed by the manufacturer; confirm before purchase\u003c\/td\u003e\n\u003ctd\u003e75692 family \/ Sierra 18-3553\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eJohnson\/Evinrude\u003c\/td\u003e\n\u003ctd\u003eE-TEC applications\u003c\/td\u003e\n\u003ctd\u003e40–250\u003c\/td\u003e\n\u003ctd\u003e2-stroke E-TEC\u003c\/td\u003e\n\u003ctd\u003eVerify model and year\u003c\/td\u003e\n\u003ctd\u003e393659, 434841, 378065, 508626, 5005440\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eJohnson\/Evinrude\u003c\/td\u003e\n\u003ctd\u003eVarious outboard applications\u003c\/td\u003e\n\u003ctd\u003e6–55\u003c\/td\u003e\n\u003ctd\u003e2-stroke\u003c\/td\u003e\n\u003ctd\u003eVerify model and year\u003c\/td\u003e\n\u003ctd\u003eListed Johnson\/Evinrude references\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eJohnson\/Evinrude\u003c\/td\u003e\n\u003ctd\u003e9.9 HP and 15 HP applications\u003c\/td\u003e\n\u003ctd\u003e9.9 \/ 15\u003c\/td\u003e\n\u003ctd\u003e4-stroke\u003c\/td\u003e\n\u003ctd\u003e1994–2001\u003c\/td\u003e\n\u003ctd\u003eListed Johnson\/Evinrude references\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eJohnson\/Evinrude\u003c\/td\u003e\n\u003ctd\u003eCrossflow V4 and V6 applications\u003c\/td\u003e\n\u003ctd\u003eVerify engine rating\u003c\/td\u003e\n\u003ctd\u003e2-stroke V4\/V6\u003c\/td\u003e\n\u003ctd\u003eVerify model and year\u003c\/td\u003e\n\u003ctd\u003eListed Johnson\/Evinrude references\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\u003eTechnical Specs\u003c\/h2\u003e\n  \u003cdl\u003e\n    \u003cdt\u003eProduct Type\u003c\/dt\u003e\n    \u003cdd\u003eMarine outboard thermostat\u003c\/dd\u003e\n    \u003cdt\u003eTemperature Rating\u003c\/dt\u003e\n    \u003cdd\u003e143°F (62°C)\u003c\/dd\u003e\n    \u003cdt\u003eProduct Configuration\u003c\/dt\u003e\n    \u003cdd\u003eSingle thermostat; not a seals or gasket kit\u003c\/dd\u003e\n    \u003cdt\u003eInstallation\u003c\/dt\u003e\n    \u003cdd\u003eDirect replacement when the reference number and complete fitment conditions match\u003c\/dd\u003e\n    \u003cdt\u003eBrand Status\u003c\/dt\u003e\n    \u003cdd\u003eAftermarket replacement, not OEM-branded\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 143°F (62°C) thermostat\u003c\/li\u003e\n  \u003c\/ul\u003e\n  \u003cp\u003eGaskets, seals, carriers, poppets, washers, and other service parts are not included unless specifically stated in the package contents.\u003c\/p\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n  \u003col\u003e\n    \u003cli\u003eSwitch off the engine, allow it to cool completely, and follow the service manual’s safety procedure.\u003c\/li\u003e\n    \u003cli\u003eConfirm the thermostat reference, engine model, horsepower, stroke type, and serial number before removing the original part.\u003c\/li\u003e\n    \u003cli\u003eLocate the thermostat housing and place a suitable drain pan beneath the work area if water may drain during service.\u003c\/li\u003e\n    \u003cli\u003eRemove the housing cover and note the orientation of the original thermostat.\u003c\/li\u003e\n    \u003cli\u003eClean the mating surfaces carefully and remove old gasket material without damaging the housing.\u003c\/li\u003e\n    \u003cli\u003eInstall the replacement thermostat in the correct orientation. Use a new gasket or seal if required by the engine service manual; none is included with this single thermostat.\u003c\/li\u003e\n    \u003cli\u003eReinstall the housing cover and tighten fasteners evenly to the manufacturer’s specified torque.\u003c\/li\u003e\n    \u003cli\u003eRun the engine according to the service manual and check for water leakage and proper cooling-system operation.\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 an outboard thermostat may be failing?\u003c\/summary\u003e\n    \u003cp\u003ePossible symptoms include overheating, an engine that runs unusually cool, poor temperature stability, restricted cooling-water flow, or a thermostat that is visibly corroded or stuck open or closed. Diagnose the complete cooling system before replacing the thermostat.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhy is the 143°F rating important?\u003c\/summary\u003e\n    \u003cp\u003eThe thermostat controls the engine’s operating temperature within the range specified for the application. Use the temperature rating required by your exact engine; do not substitute a different rating solely because the part looks similar.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eCan this thermostat be used in saltwater?\u003c\/summary\u003e\n    \u003cp\u003eIt is intended for the listed marine outboard applications. Saltwater use increases corrosion risk, so follow the engine manufacturer’s flushing and cooling-system maintenance recommendations.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eIs a new gasket required?\u003c\/summary\u003e\n    \u003cp\u003eA new gasket or seal is commonly recommended when servicing a thermostat housing, but this listing contains the thermostat only. Select the gasket specified for your exact engine separately if required.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eIs this an OEM thermostat?\u003c\/summary\u003e\n    \u003cp\u003eNo. This is an aftermarket replacement intended to match the listed manufacturer references and fitment conditions. Mercury, Mariner, Johnson, Evinrude, OMC, Sierra, and GLM references are used for identification and cross-reference purposes only.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow should I verify fitment?\u003c\/summary\u003e\n    \u003cp\u003eCompare the complete reference number and thermostat temperature rating, then verify the engine brand, model, horsepower, stroke or engine type, year where applicable, and serial-number range. If any of these details differ, consult the engine service manual before ordering.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eShipping speed and cost\u003c\/summary\u003e\n    \u003cp\u003eAvailable shipping methods, delivery estimates, and shipping charges are shown at checkout and may vary by destination.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWarranty and returns\u003c\/summary\u003e\n    \u003cp\u003eWarranty coverage and return eligibility are governed by the current store policies. Contact customer support with your order details if the part arrives damaged or appears to be incorrect.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eSafety \u0026amp; Important Info\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eVerify the complete application and reference number before purchase; horsepower alone does not confirm compatibility.\u003c\/li\u003e\n    \u003cli\u003eDo not rely on a general model range when the engine has a specific serial-number condition.\u003c\/li\u003e\n    \u003cli\u003eAllow the engine to cool before opening the thermostat housing.\u003c\/li\u003e\n    \u003cli\u003eUse the manufacturer’s service manual for torque values, gasket requirements, orientation, and cooling-system testing.\u003c\/li\u003e\n    \u003cli\u003eThis is an aftermarket replacement, not an OEM component.\u003c\/li\u003e\n    \u003cli\u003eProfessional installation is recommended when the correct procedure or fitment is uncertain.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\u003csection\u003e\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 marine components selected for listed applications and service needs.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eApplication-Focused Listings\u003c\/strong\u003e — Confirm model, reference, and serial conditions before ordering.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eCustomer Support\u003c\/strong\u003e — Contact us with your engine details and existing part reference when you need help checking fitment.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50723981132091,"sku":"20TH005","price":26.4,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/Outboard_Thermostat_for_Johnson_Evinrude_6-250_HP_V4_V6_Outboard_Motors_______5005440_-_JLM_MARINE-8286946.jpg?v=1763039251"}],"url":"https:\/\/seasierra.com\/collections\/yamaha-2-stroke-outboard-marine-engine-parts-4.oembed","provider":"SeaSierra","version":"1.0","type":"link"}