{"title":"Mercury 4-Stroke 5-235HP Outboard Marine Parts","description":"\u003csection id=\"hero\" style=\"padding:16px;border:1px solid #e5e5e5;border-radius:8px;max-width:1000px;\"\u003e\n  \u003cp\u003eThis page is built for Mercury 4-Stroke 5–235HP outboard engines. Use it to find compatible parts and practical service guidance. Below you’ll find maintenance tips, frequently used replacement parts, and troubleshooting checks. 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 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\/mercury-outboard-parts\" style=\"display:inline-block;padding:10px 14px;background:#0a4d8c;color:#fff;text-decoration:none;border-radius:6px;\"\u003eBrowse All Mercury Parts\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"identify-model\" style=\"padding:16px;max-width:1000px;\"\u003e\n  \u003ch2\u003eHow to Identify Your 5–235HP Model\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eFind the serial\/nameplate on the swivel bracket (port or starboard) or the identification plate near the steering tube. Record the full serial number.\u003c\/li\u003e\n    \u003cli\u003eRead the model code and suffix: letters typically indicate shaft length (S\/L\/XL), start\/controls (manual\/electric; tiller\/remote), and other options.\u003c\/li\u003e\n    \u003cli\u003eConfirm platform: smaller 5–25HP engines are compact portable four-strokes; mid-range 30–115HP are commonly inline EFI four-strokes; larger 150–235HP models may be inline-4 or V6 EFI. Cowl size and cylinder count help distinguish them.\u003c\/li\u003e\n    \u003cli\u003eFor accurate parts matching, note horsepower, serial number, shaft length, and whether the engine uses carburetion or EFI.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"engine-overview\" style=\"padding:16px;max-width:1000px;\"\u003e\n  \u003ch2\u003ePlatform Overview\u003c\/h2\u003e\n\n  \u003ch3\u003ePortable \u0026amp; Inshore (5–25HP)\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;\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;\"\u003eDescription\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eSingle- or twin-cylinder 4-stroke, carbureted or EFI depending on year; manual or electric start; tiller or remote options.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e5HP, 6HP, 8–9.9HP, 15–20HP, 25HP FourStroke variants.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eLightweight, easy to service, sips fuel, ideal for tenders, jon boats, and small skiffs.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eImpeller and spark plugs are common service items. Verify prop hub style and gear ratio by serial number.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\n  \u003ch3\u003eMid‑Range EFI (30–115HP)\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;\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;\"\u003eDescription\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eInline-3 or Inline-4 4-stroke EFI; remote control or tiller kits; power trim\/tilt common.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e30–60HP EFI, 75–90HP EFI, 100–115HP EFI FourStroke families.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eStrong mid‑range torque, smooth idle, good fuel economy for bay boats, pontoons, and runabouts.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eKeep EFI filters clean and maintain battery health for reliable starting and charging performance.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\n  \u003ch3\u003eOffshore \u0026amp; High Output (150–235HP)\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;\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;\"\u003eDescription\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eLarge-displacement Inline‑4 or V6 4-stroke EFI; robust gearcases; hydraulic or digital controls depending on rig.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e150HP FourStroke, and higher-horsepower FourStroke families up to 235HP.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eHigh thrust, dependable offshore performance, supports heavier hulls and multi‑engine setups.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eService intervals and filter specifications vary by serial range; confirm by serial number and control system type.\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;max-width:1000px;\"\u003e\n  \u003ch2\u003eRoutine Maintenance \u0026amp; Service Parts\u003c\/h2\u003e\n  \u003cp\u003eIntervals below are general guidelines for 4-stroke outboards. Always follow the official Mercury service manual for your exact model and serial number.\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;\"\u003eItem\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;\"\u003eInterval*\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;\"\u003eRemarks\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;\"\u003eParts Link\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eEngine oil \u0026amp; filter\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eUse marine 4-stroke oil meeting Mercury specs; replace filter at each oil change.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/oil-filters\"\u003eShop Oil Filters\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eGear oil (lower unit)\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eInspect for water intrusion or metal. Replace drain\/fill gaskets.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\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:6px 0;\"\u003eSpark plugs\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eCheck gap and replace if fouled or worn. Heat range varies by platform.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/spark-plug\"\u003eShop Spark Plugs\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eFuel filter \/ inline filter\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eInspect each 50 hours; replace 100 hours\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eCritical for EFI reliability; drain any water and replace as needed.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/fuel-filters-1\"\u003eShop Fuel Filters\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eWater pump impeller\/kit\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eEvery 2–3 seasons or 200 hours\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eReplace sooner if stream is weak, after sand\/silt use, or overheating event.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\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:6px 0;\"\u003eAnodes\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eInspect every 50 hours; replace when 50% depleted\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eSelect zinc, aluminum, or magnesium based on water type (salt, brackish, fresh).\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/anodes\"\u003eShop Anodes\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eTiming belt (where equipped)\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eInspect 200–300 hours\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eCheck tension and condition; replace per manual for your serial range.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\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=\"padding:16px;max-width:1000px;\"\u003e\n  \u003ch2\u003eFrequently Used Parts Categories\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eRoutine Service — \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\u003eCooling System — \u003ca href=\"https:\/\/seasierra.com\/collections\/water-pumps\"\u003eWater Pumps\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 | \u003ca href=\"https:\/\/seasierra.com\/collections\/fuel-pumps\"\u003eFuel Pumps\u003c\/a\u003e | \u003ca href=\"https:\/\/seasierra.com\/collections\/injectors\"\u003eInjectors\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eIgnition \/ Electrical — \u003ca href=\"https:\/\/seasierra.com\/collections\/starters\"\u003eStarters\u003c\/a\u003e | \u003ca href=\"https:\/\/seasierra.com\/collections\/sensors\"\u003eSensors\u003c\/a\u003e | \u003ca href=\"https:\/\/seasierra.com\/collections\/rectifiers\"\u003eRectifiers\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eGearcase \u0026amp; Propulsion — \u003ca href=\"https:\/\/seasierra.com\/collections\/propellers\"\u003ePropellers\u003c\/a\u003e | \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\u003eCorrosion Protection — \u003ca href=\"https:\/\/seasierra.com\/collections\/anodes\"\u003eAnodes\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eControls \u0026amp; Rigging — \u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-outboard-parts\"\u003eMercury Outboard Parts\u003c\/a\u003e\n\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"troubleshooting\" style=\"padding:16px;max-width:1000px;\"\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;\"\u003eSymptom\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;\"\u003eCheck First\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #ddd;\"\u003eRelated Parts\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eWeak telltale stream or overheat alarm\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eInspect intake screens for debris; verify impeller condition; check thermostat operation.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eWater pump kit, thermostat, intake screen, anodes\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003ePoor acceleration or power loss\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eCheck for damaged prop, old fuel, clogged fuel filter, fouled plugs; confirm throttle opens fully.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003ePropeller, fuel filter, spark plugs, injectors, fuel pump\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eHard starting or rough idle\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eVerify battery charge and connections; examine plugs; look for air leaks on fuel side.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eSpark plugs, starter, sensors, injectors, fuel pump\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eGearcase noise or metal in gear oil\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eCheck oil level and color; test for water intrusion; inspect prop shaft for fishing line damage.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eLower unit seal kit, bearings, seals, gear set\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eCharging issues (low or over‑voltage)\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eMeasure battery voltage at idle\/fast idle; inspect regulator\/rectifier connectors and fuses.\u003c\/td\u003e\n        \u003ctd style=\"padding:6px 0;\"\u003eRectifier\/regulator, alternator (where equipped), wiring\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;max-width:1000px;\"\u003e\n  \u003ch2\u003eFAQs\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eAre parts interchangeable across years or platforms?\u003c\/summary\u003e\n    \u003cp\u003eSome components interchange within the same platform and displacement, but many parts are serial‑number specific. Always confirm by serial number and horsepower to ensure a correct fit.\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, every 2–3 seasons or about 200 hours. Replace sooner if you notice a weak telltale, overheating, or you operate in sandy\/silty water.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow often should I change gear oil?\u003c\/summary\u003e\n    \u003cp\u003eInspect periodically and replace every 100 hours or annually. If oil appears milky or metallic, service the gearcase and seals before further operation.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat information is needed to confirm part compatibility?\u003c\/summary\u003e\n    \u003cp\u003eProvide the engine’s serial number, horsepower, approximate year, shaft length (S\/L\/XL), and whether it’s tiller or remote control. Photos of the nameplate and the part in question are helpful.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"cta\" style=\"padding:16px;border-top:1px solid #e5e5e5;max-width:1000px;\"\u003e\n  \u003cp\u003eReady to find parts by horsepower, year, and model? Explore the full Mercury outboard collection and refine with Filter \u0026amp; Sort.\u003c\/p\u003e\n  \u003cp\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercury-outboard-parts\" style=\"display:inline-block;padding:10px 14px;background:#0a4d8c;color:#fff;text-decoration:none;border-radius:6px;\"\u003eShop Mercury Outboard Parts\u003c\/a\u003e\u003c\/p\u003e\n  \u003cp style=\"font-size:0.95em;color:#555;\"\u003eIf you’re unsure about your model, send us a clear photo of the nameplate and the part you need and we’ll help verify compatibility.\u003c\/p\u003e\n\u003c\/section\u003e","products":[],"url":"https:\/\/seasierra.com\/collections\/mercury-4-stroke-5-235hp-outboard-marine-parts.oembed","provider":"SeaSierra","version":"1.0","type":"link"}