{"title":"Mercury Mariner 3.5HP 2-Stroke Outboard Engine Parts","description":"\u003csection id=\"hero\" style=\"padding:16px; border:1px solid #e5e5e5; border-radius:8px;\"\u003e\n  \u003cp\u003eThis page is dedicated to Mercury\/Mariner 3.5HP 2‑Stroke outboard engines. Use it to find compatible parts and practical service information, including maintenance tips, common replacement items, and troubleshooting guidance. You can also browse the main Mercury collection. Scroll to the bottom of the page to start browsing parts for this engine, and remember you can use the Filter \u0026amp; Sort controls on the collection page 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; padding:10px 14px; background:#1a73e8; 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=\"margin-top:24px;\"\u003e\n  \u003ch2\u003eHow to Identify Your 3.5HP Model\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eSerial\/ID plate location: typically on the port (left) side of the transom bracket or swivel bracket. The sticker on the clamp bracket also repeats this information.\u003c\/li\u003e\n    \u003cli\u003eModel code and suffix: look for shaft length (S = 15\" short, L = 20\" long), tiller\/manual start vs. remote options, and regional suffixes. Record the full code and serial to confirm parts.\u003c\/li\u003e\n    \u003cli\u003eBranding: Mercury and Mariner versions share the same small portable platform; parts are often interchangeable, but always verify by serial.\u003c\/li\u003e\n    \u003cli\u003e2‑Stroke identifier: single‑cylinder, carbureted design with premix fuel (no engine oil sump). A primer\/choke and a top‑mounted recoil starter are typical.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"engine-overview\" style=\"margin-top:24px;\"\u003e\n  \u003ch2\u003eEngine Overview\u003c\/h2\u003e\n  \u003ch3\u003ePortable Single‑Cylinder 2‑Stroke\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 #ddd; padding:8px;\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left; border-bottom:1px solid #ddd; 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 #f0f0f0;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eSingle‑cylinder, reed‑valve, carbureted 2‑Stroke; water‑cooled with impeller; manual start, tiller steer.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eMercury\/Mariner 3.5HP 2‑Stroke in short (15\") and long (20\") shaft variants; manual choke\/primer carburetor.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eVery light and portable, simple maintenance, reliable cooling with fresh impeller, economical at displacement speeds.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eUse fresh 50:1 premix (TC‑W3 2‑stroke oil) unless otherwise specified on the engine decal. Regular impeller service is critical to avoid overheating.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"service-kits\" style=\"margin-top:24px;\"\u003e\n  \u003ch2\u003eRoutine Maintenance \u0026amp; Service Parts\u003c\/h2\u003e\n  \u003cp\u003eIntervals below are general guidelines for small 2‑Stroke portables. Always confirm specifications and procedures with your 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 #ddd; padding:8px;\"\u003eItem\u003c\/th\u003e\n        \u003cth style=\"text-align:left; border-bottom:1px solid #ddd; padding:8px;\"\u003eInterval*\u003c\/th\u003e\n        \u003cth style=\"text-align:left; border-bottom:1px solid #ddd; padding:8px;\"\u003eRemarks\u003c\/th\u003e\n        \u003cth style=\"text-align:left; border-bottom:1px solid #ddd; 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 #f0f0f0;\"\u003eLower unit gear oil\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eCheck for water or metal; reseal if milky or low.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\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 #f0f0f0;\"\u003eSpark plugs\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eInspect 50 hours; replace 100 hours\/annual\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eVerify heat range and gap; carry a spare on board.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\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 #f0f0f0;\"\u003eInline fuel filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eInspect 50 hours or each season\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eReplace if restricted or water‑contaminated; keep fuel clean.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\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 #f0f0f0;\"\u003eWater pump impeller\/kit\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eEvery 2 seasons or 200 hours (sooner in sandy\/silty water)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eEssential for cooling; replace housing\/plate if scored.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\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 #f0f0f0;\"\u003eAnodes (zincs)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eInspect 50 hours; replace when 50% consumed\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eChoose alloy for your water (salt\/brackish\/fresh).\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\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 #f0f0f0;\"\u003eFuel line \u0026amp; primer bulb\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eAnnually or at first signs of cracking\/softening\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eEthanol can degrade hoses; replace if sticky or collapsed.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/hoses\"\u003eHoses\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003ePropeller \u0026amp; shear pin\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eInspect each outing; replace as needed\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eCarry spare pin; check for bent blades or hub damage.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/propellers\"\u003ePropellers\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eLower unit seal kit (if water ingress)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eAs needed after leak test\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003ePressure\/vacuum test the gearcase after impact or water‑in‑oil.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\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      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003e2‑Stroke fuel mix (TC‑W3)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eEvery refuel (typ. 50:1)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eUse fresh gasoline and quality TC‑W3 oil; verify ratio on your cowl decal.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-outboard-parts\"\u003eMercury Outboard Parts\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=\"margin-top:24px;\"\u003e\n  \u003ch2\u003eFrequently Used Parts Categories\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eRoutine Service: \u003ca href=\"https:\/\/seasierra.com\/collections\/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\u003eGearcase \u0026amp; Seals: \u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-lower-unit-seal-kits\"\u003eMercury 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 \/ Tune‑Up: \u003ca href=\"https:\/\/seasierra.com\/collections\/spark-plug\"\u003eSpark Plugs\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 \u0026amp; Safety: \u003ca href=\"https:\/\/seasierra.com\/collections\/propellers\"\u003ePropellers\u003c\/a\u003e and \u003ca href=\"https:\/\/seasierra.com\/collections\/propeller-guards\"\u003ePropeller Guards\u003c\/a\u003e\n\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"troubleshooting\" style=\"margin-top:24px;\"\u003e\n  \u003ch2\u003eCommon Symptoms \u0026amp; Quick Checks\u003c\/h2\u003e\n  \u003ctable style=\"width:100%; border-collapse:collapse;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left; border-bottom:1px solid #ddd; padding:8px;\"\u003eSymptom\u003c\/th\u003e\n        \u003cth style=\"text-align:left; border-bottom:1px solid #ddd; padding:8px;\"\u003eCheck First\u003c\/th\u003e\n        \u003cth style=\"text-align:left; border-bottom:1px solid #ddd; 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 #f0f0f0;\"\u003eWeak tell‑tale or overheat alarm\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eDebris on intake screen, impeller wear, thermostat sticking, kinked tell‑tale hose.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eWater pump kit, intake screen, thermostat, gaskets.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eHard starting \/ rough idle\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eOld fuel, flooded carb, choke\/primer use, idle mixture \u0026amp; speed, plug gap.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eSpark plugs, inline fuel filter, fuel hoses, carb gaskets.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003ePoor acceleration \/ power loss\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eProp damage, sheared pin, restricted fuel flow, vent closed, low compression.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003ePropeller, shear pin, fuel filter, spark plugs.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eExcessive smoke (2‑Stroke)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eOver‑rich oil mix, extended cold idle, fouled plug, low‑speed carb circuit rich.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px; border-bottom:1px solid #f0f0f0;\"\u003eSpark plugs, fuel\/oil mix supplies.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eGearcase noise or metal in oil\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eLow\/contaminated gear oil, fishing line on prop shaft, worn bearings after impact.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eLower unit seal kit, prop shaft seals, 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=\"margin-top:24px;\"\u003e\n  \u003ch2\u003eFAQs\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eAre Mercury and Mariner 3.5HP 2‑Stroke parts interchangeable across years?\u003c\/summary\u003e\n    \u003cp\u003eMany components are shared between Mercury and Mariner 3.5HP 2‑Stroke variants, but running changes exist. Always verify with your full serial\/ID and shaft length to ensure an exact match.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow often should I replace the water pump impeller?\u003c\/summary\u003e\n    \u003cp\u003eAs a preventive service, every 2 seasons or about 200 hours—sooner if you operate in sand, silt, or shallow weedy water. Replace the full kit (impeller, key, gaskets, and wear plate\/housing) if parts are worn.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhen should the gear oil be changed?\u003c\/summary\u003e\n    \u003cp\u003eChange lower unit gear oil at least annually or every 100 hours. If the oil appears milky or you suspect a leak after an impact, perform a pressure\/vacuum test and reseal the gearcase before refilling.\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 serial number, model designation, shaft length (15\" or 20\"), starting\/steering type (manual\/tiller), and any visible part numbers or dimensions from the component you’re replacing.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"cta\" style=\"margin-top:24px; padding:16px; border:1px solid #e5e5e5; border-radius:8px;\"\u003e\n  \u003cp\u003eReady to find parts? Browse the main Mercury collection to filter by horsepower, year, and model, then select the components that fit your 3.5HP 2‑Stroke.\u003c\/p\u003e\n  \u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-outboard-parts\" style=\"display:inline-block; margin-top:8px; padding:10px 14px; background:#1a73e8; color:#fff; text-decoration:none; border-radius:6px;\"\u003eShop Mercury Outboard Parts\u003c\/a\u003e\n  \u003cp style=\"margin-top:8px; 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":"water-pump-impeller-kit-fits-mercury-mariner-2-stroke-3-5-9-8-hp-replaces-47-89980t1-47-89980q1","title":"Water Pump Impeller Kit – Fits Mercury Mariner 2-Stroke 3.5–9.8 HP (Replaces 47-89980T1, 47-89980Q1)","description":"\u003csection\u003e\n\u003cstyle\u003e\n  .ss-table-wrap { overflow-x:auto; -webkit-overflow-scrolling:touch; }\n  table.ss-table { width:100%; border-collapse:collapse; min-width:640px; }\n  table.ss-table th, table.ss-table td { 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\n\u003ch2\u003eProduct Details\u003c\/h2\u003e\n\u003cp\u003eThis \u003cstrong\u003ewater pump impeller kit\u003c\/strong\u003e is designed for selected Mercury and Mariner 2-stroke outboard motors in the 3.5–9.8 HP range, including 3.5 HP, 3.6 HP, 3.9 HP, 4 HP, 4.5 HP, 7.5 HP, and 9.8 HP models manufactured during the listed model years. Please verify the exact model, year, serial number, and impeller dimensions before ordering.\u003c\/p\u003e\n\u003cp\u003eThe kit is listed as a replacement for Mercury references including \u003cstrong\u003e47-89980T1\u003c\/strong\u003e, \u003cstrong\u003e47-89980Q1\u003c\/strong\u003e, \u003cstrong\u003e89980\u003c\/strong\u003e, \u003cstrong\u003e89980B\u003c\/strong\u003e, and \u003cstrong\u003e68988\u003c\/strong\u003e, as well as aftermarket references such as Sierra \u003cstrong\u003e18-3054\u003c\/strong\u003e, GLM \u003cstrong\u003e12270\u003c\/strong\u003e, and CEF \u003cstrong\u003e500314\u003c\/strong\u003e. These references should be used for cross-checking only; always compare the original part and engine serial number.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eInstalls in the lower unit water pump to restore cooling-water circulation.\u003c\/li\u003e\n\u003cli\u003eIncludes a neoprene impeller and stainless steel wear plate for dependable service.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCritical fitment note:\u003c\/strong\u003e This kit uses a 0.438 in (11.1 mm) impeller inside diameter. Measure the existing impeller or driveshaft before purchase.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n\u003cp\u003eUse these references to cross-check the replacement part across OEM and aftermarket catalogs.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\u003ctable class=\"ss-table\" aria-label=\"Part Number Interchange References\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eBrand\u003c\/th\u003e\n\u003cth\u003ePart Number\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eMercury\u003c\/td\u003e\n\u003ctd\u003e47-89980T1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMercury\u003c\/td\u003e\n\u003ctd\u003e47-89980Q1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMercury\u003c\/td\u003e\n\u003ctd\u003e89980\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMercury\u003c\/td\u003e\n\u003ctd\u003e89980B\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMercury\u003c\/td\u003e\n\u003ctd\u003e68988\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-3054\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGLM\u003c\/td\u003e\n\u003ctd\u003e12270\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCEF\u003c\/td\u003e\n\u003ctd\u003e500314\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003c\/div\u003e\n\n\u003ch2\u003eEngine \u0026amp; Model Compatibility\u003c\/h2\u003e\n\u003cp\u003eThe following model and year information is provided as a compatibility guide. Confirm the engine model, production origin, serial number, and impeller dimensions before ordering.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\u003ctable class=\"ss-table\" aria-label=\"Compatible Mercury and Mariner Models\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eBrand\u003c\/th\u003e\n\u003cth\u003eModel\u003c\/th\u003e\n\u003cth\u003eRated HP\u003c\/th\u003e\n\u003cth\u003eStroke\u003c\/th\u003e\n\u003cth\u003eYears\u003c\/th\u003e\n\u003cth\u003eOEM Part No.\u003c\/th\u003e\n\u003cth\u003eNotes\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\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\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1983–1985\u003c\/td\u003e\n\u003ctd\u003e47-89980T1\u003c\/td\u003e\n\u003ctd\u003e0.438 in impeller I.D.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n\u003ctd\u003e3.6 HP\u003c\/td\u003e\n\u003ctd\u003e3.6\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1980–1982\u003c\/td\u003e\n\u003ctd\u003e47-89980T1\u003c\/td\u003e\n\u003ctd\u003e0.438 in impeller I.D.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n\u003ctd\u003e3.9 HP\u003c\/td\u003e\n\u003ctd\u003e3.9\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1979–1985\u003c\/td\u003e\n\u003ctd\u003e47-89980T1\u003c\/td\u003e\n\u003ctd\u003e0.438 in impeller I.D.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n\u003ctd\u003e4 HP, 1 cylinder\u003c\/td\u003e\n\u003ctd\u003e4\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1982–1986\u003c\/td\u003e\n\u003ctd\u003e47-89980T1\u003c\/td\u003e\n\u003ctd\u003e0.438 in impeller I.D.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n\u003ctd\u003e4 HP (40), 2 cylinder\u003c\/td\u003e\n\u003ctd\u003e4\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1980–1981\u003c\/td\u003e\n\u003ctd\u003e47-89980T1\u003c\/td\u003e\n\u003ctd\u003e0.438 in impeller I.D.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n\u003ctd\u003e4.5 HP, 1 cylinder\u003c\/td\u003e\n\u003ctd\u003e4.5\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1980–1985\u003c\/td\u003e\n\u003ctd\u003e47-89980T1\u003c\/td\u003e\n\u003ctd\u003e0.438 in impeller I.D.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n\u003ctd\u003e7.5 HP\u003c\/td\u003e\n\u003ctd\u003e7.5\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1979–1986\u003c\/td\u003e\n\u003ctd\u003e47-89980T1\u003c\/td\u003e\n\u003ctd\u003e0.438 in impeller I.D.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n\u003ctd\u003e9.8 HP\u003c\/td\u003e\n\u003ctd\u003e9.8\u003c\/td\u003e\n\u003ctd\u003e2-Stroke\u003c\/td\u003e\n\u003ctd\u003e1979–1985\u003c\/td\u003e\n\u003ctd\u003e47-89980T1\u003c\/td\u003e\n\u003ctd\u003e0.438 in impeller I.D.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003c\/div\u003e\n\n\u003ch3\u003eSerial Number Compatibility\u003c\/h3\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\u003ctable class=\"ss-table\" aria-label=\"Compatible Serial Number Ranges\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eOrigin\u003c\/th\u003e\n\u003cth\u003eModel\u003c\/th\u003e\n\u003cth\u003eSerial Range\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eUSA Made\u003c\/td\u003e\n\u003ctd\u003e9.8 HP\u003c\/td\u003e\n\u003ctd\u003e5206550 and up\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUSA Made\u003c\/td\u003e\n\u003ctd\u003e7.5 HP\u003c\/td\u003e\n\u003ctd\u003e5206550 and up\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUSA Made\u003c\/td\u003e\n\u003ctd\u003e4.5 HP, 1 cylinder\u003c\/td\u003e\n\u003ctd\u003e5595532 and up\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUSA Made\u003c\/td\u003e\n\u003ctd\u003e4 HP, 1 cylinder\u003c\/td\u003e\n\u003ctd\u003e5595532–0A809600\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBEL Made\u003c\/td\u003e\n\u003ctd\u003e9.8 HP\u003c\/td\u003e\n\u003ctd\u003e9217756 and up\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBEL Made\u003c\/td\u003e\n\u003ctd\u003e7.5 HP\u003c\/td\u003e\n\u003ctd\u003e9217756 and up\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBEL Made\u003c\/td\u003e\n\u003ctd\u003e4.5 HP, 1 cylinder\u003c\/td\u003e\n\u003ctd\u003e9258281 and up\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBEL Made\u003c\/td\u003e\n\u003ctd\u003e4 HP, 1 cylinder\u003c\/td\u003e\n\u003ctd\u003e9258281–9477829\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCAN Made\u003c\/td\u003e\n\u003ctd\u003e9.8 HP\u003c\/td\u003e\n\u003ctd\u003e7125388 and up\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCAN Made\u003c\/td\u003e\n\u003ctd\u003e7.5 HP\u003c\/td\u003e\n\u003ctd\u003e7125388 and up\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCAN Made\u003c\/td\u003e\n\u003ctd\u003e4.5 HP, 1 cylinder\u003c\/td\u003e\n\u003ctd\u003e7147238 and up\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCAN Made\u003c\/td\u003e\n\u003ctd\u003e4 HP, 1 cylinder\u003c\/td\u003e\n\u003ctd\u003e7143688 and up\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAUS Made\u003c\/td\u003e\n\u003ctd\u003e9.8 HP\u003c\/td\u003e\n\u003ctd\u003e8057545 and up\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAUS Made\u003c\/td\u003e\n\u003ctd\u003e7.5 HP\u003c\/td\u003e\n\u003ctd\u003e8057545 and up\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAUS Made\u003c\/td\u003e\n\u003ctd\u003e4.5 HP, 1 cylinder\u003c\/td\u003e\n\u003ctd\u003e8068065 and up\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAUS Made\u003c\/td\u003e\n\u003ctd\u003e4 HP, 1 cylinder\u003c\/td\u003e\n\u003ctd\u003e8068065 and up\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003c\/div\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003cdl\u003e\n\u003cdt\u003eProduct Type\u003c\/dt\u003e\n\u003cdd\u003eWater pump impeller kit\u003c\/dd\u003e\n\u003cdt\u003eInstallation Location\u003c\/dt\u003e\n\u003cdd\u003eLower unit and driveshaft water pump\u003c\/dd\u003e\n\u003cdt\u003eMaterials\u003c\/dt\u003e\n\u003cdd\u003eNeoprene impeller, SS316 wear plate, nylon PA66 tube\u003c\/dd\u003e\n\u003cdt\u003eImpeller Blades\u003c\/dt\u003e\n\u003cdd\u003e6\u003c\/dd\u003e\n\u003cdt\u003eImpeller Height\u003c\/dt\u003e\n\u003cdd\u003e14.4 mm (0.57 in)\u003c\/dd\u003e\n\u003cdt\u003eImpeller Inside Diameter\u003c\/dt\u003e\n\u003cdd\u003e11.1 mm (0.438 in)\u003c\/dd\u003e\n\u003cdt\u003eImpeller Outside Diameter\u003c\/dt\u003e\n\u003cdd\u003e31.8 mm (1.250 in)\u003c\/dd\u003e\n\u003cdt\u003eFitting Type\u003c\/dt\u003e\n\u003cdd\u003eInternal shaft mounting\u003c\/dd\u003e\n\u003cdt\u003eWeight\u003c\/dt\u003e\n\u003cdd\u003e23 g (0.811 oz)\u003c\/dd\u003e\n\u003c\/dl\u003e\n\n\u003ch2\u003eWhat's in the Box\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e1 × Impeller, replacement for 47-89980 and 89980B references\u003c\/li\u003e\n\u003cli\u003e1 × Wear plate, replacement for 46895 reference\u003c\/li\u003e\n\u003cli\u003e1 × Woodruff key\u003c\/li\u003e\n\u003cli\u003e1 × Water guide tube sleeve\u003c\/li\u003e\n\u003cli\u003e3 × O-rings\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n\u003cli\u003e\n\u003cstrong\u003eConfirm fitment first:\u003c\/strong\u003e Mercury used different driveshaft and impeller dimensions in some horsepower ranges. This kit is for the smaller 0.438 in impeller inside diameter. Do not install it if the original impeller has a larger opening.\u003c\/li\u003e\n\u003cli\u003eDisconnect the spark plug leads to prevent accidental starting and place the outboard in neutral.\u003c\/li\u003e\n\u003cli\u003eRemove the bolts securing the lower unit to the upper leg. Lower the unit carefully while observing the shift-shaft linkage.\u003c\/li\u003e\n\u003cli\u003ePlace the lower unit on a stable workbench and remove the water pump housing.\u003c\/li\u003e\n\u003cli\u003eRemove the old impeller, wear plate, gaskets, and seals. Note the orientation of each part.\u003c\/li\u003e\n\u003cli\u003eClean the mating surfaces and remove old gasket material, debris, and corrosion.\u003c\/li\u003e\n\u003cli\u003eInstall the replacement wear plate, gaskets, and O-rings included in the kit.\u003c\/li\u003e\n\u003cli\u003eInstall the new impeller on the driveshaft with the Woodruff key correctly seated. A small amount of dish soap may be used to lubricate the housing interior.\u003c\/li\u003e\n\u003cli\u003eRotate the driveshaft clockwise while lowering the pump housing over the impeller so the blades set correctly.\u003c\/li\u003e\n\u003cli\u003eSecure the housing and tighten its fasteners to the engine manufacturer's recommended torque.\u003c\/li\u003e\n\u003cli\u003eReinstall the lower unit, aligning the water tube, driveshaft splines, and shift shaft.\u003c\/li\u003e\n\u003cli\u003eTest the engine with an appropriate water supply, such as flushing muffs or a test tank, and check for a strong tell-tale stream.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\u003csummary\u003eHow do I know if this impeller is the right size?\u003c\/summary\u003e\u003cp\u003eThe impeller inside diameter must match the driveshaft. This kit uses a 0.438 in (11.1 mm) inside diameter. Some Mercury and Mariner models in this horsepower range use a larger 0.456 in impeller. Measure the old impeller or driveshaft and verify the model and serial number before ordering.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat are the signs of a failing water pump impeller?\u003c\/summary\u003e\u003cp\u003eTypical signs include a weak or absent tell-tale stream, an overheating warning, elevated operating temperature, or reduced cooling performance. A rubber impeller may become brittle, cracked, distorted, or worn with use.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eHow often should I replace the impeller?\u003c\/summary\u003e\u003cp\u003eInspect the impeller regularly and consider replacement every 1–2 years or every 100–200 operating hours, depending on use and conditions such as saltwater, sand, silt, and debris.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eCan I reuse the old wear plate or gaskets?\u003c\/summary\u003e\u003cp\u003eReplacing the components supplied with the kit is recommended. A worn or grooved wear plate, damaged gasket, or hardened O-ring can reduce pump efficiency and compromise sealing.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhy are there different serial number ranges?\u003c\/summary\u003e\u003cp\u003eManufacturers may change components during a production run. The serial number can identify differences such as driveshaft or water-pump configuration, so fitment should be checked by model, year, origin, and serial number together.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eIs this part OEM or aftermarket?\u003c\/summary\u003e\u003cp\u003eThis is an aftermarket replacement part, not an OEM component. It is intended to replace the listed OEM and aftermarket references when the engine model, serial number, and dimensions match.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat are the shipping speed and cost?\u003c\/summary\u003e\u003cp\u003eStandard delivery is typically estimated at 5–15 days and may be free to most locations. Available expedited delivery methods and costs are shown at checkout when offered for your destination.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat is the warranty and return policy?\u003c\/summary\u003e\u003cp\u003eThe product is covered by a 1-year warranty against manufacturing defects under normal marine use. Returns are accepted within the applicable standard return window for unused items in original packaging. Contact support with your order information for assistance.\u003c\/p\u003e\u003c\/details\u003e\n\n\u003ch2\u003eSafety \u0026amp; Important Information\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eVerify the model, year, serial number, production origin, part dimensions, and original impeller before purchase. Pay particular attention to the \u003cstrong\u003e0.438 in (11.1 mm) impeller inside diameter\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003eThis is an aftermarket replacement part and is not manufactured by or affiliated with Mercury, Mariner, Sierra, GLM, or CEF.\u003c\/li\u003e\n\u003cli\u003eProfessional installation is recommended when you are not familiar with lower-unit service. Incorrect installation can cause overheating or engine damage.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePro-Grade Standards\u003c\/strong\u003e — We supply marine replacement parts designed for demanding saltwater and freshwater operating conditions.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFast Global Fulfillment\u003c\/strong\u003e — Standard delivery is available to most regions, with typical transit times of 5–15 days.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer-Direct Value\u003c\/strong\u003e — We work directly with manufacturers to offer competitive pricing while maintaining material and quality-control standards.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50723963633979,"sku":"BN-CX14-GD0F","price":18.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/BN-CX14-GD0F.png?v=1763038505"}],"url":"https:\/\/seasierra.com\/collections\/mercury-mariner-3-5hp-2-stroke-outboard-engine-parts.oembed","provider":"SeaSierra","version":"1.0","type":"link"}