{"title":"MerCruiser 4-Stroke Outboard Marine Engine Parts 175-430HP","description":"\u003csection id=\"hero\" style=\"padding:16px; border:1px solid #e5e7eb; border-radius:8px; max-width:1100px;\"\u003e\n  \u003cp\u003eThis page is for MerCruiser 4-Stroke 175–430HP outboard engines. Use it to quickly find compatible parts and essential service information, including maintenance tips, common replacement parts, and troubleshooting guidance. You can also browse the main MerCruiser collection. Scroll to the bottom of this page to start browsing parts for this engine. 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  \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser\" style=\"display:inline-block; padding:10px 16px; background:#0a4; color:#fff; text-decoration:none; border-radius:6px;\"\u003eBrowse All MerCruiser Parts\u003c\/a\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"identify-model\" style=\"padding:20px 0; max-width:1100px;\"\u003e\n  \u003ch2\u003eHow to Identify Your 175–430HP Model\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eLocate the model\/serial plate on the transom clamp bracket or starboard mounting bracket; record the full model code and serial number.\u003c\/li\u003e\n    \u003cli\u003eDecode suffixes for shaft length (L\/XL\/XXL), control type (mechanical or DTS), and steering configuration.\u003c\/li\u003e\n    \u003cli\u003eDistinguish platforms: many 175–225 HP are V6 EFI; higher outputs often use inline‑6 supercharged or V8 four‑stroke platforms. Cowl shape, presence of power steering\/DTS, and intake layout can help identify the family.\u003c\/li\u003e\n    \u003cli\u003eAs a 4‑stroke, your engine uses crankcase oil and a spin‑on oil filter under the cowl—verify part styles by serial number before ordering.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"engine-overview\" style=\"padding:20px 0; max-width:1100px;\"\u003e\n  \u003ch2\u003ePlatform Overview\u003c\/h2\u003e\n  \u003ch3\u003eV6 EFI Four‑Stroke (approx. 175–225 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 #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;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eFour‑stroke V6 with electronic fuel injection; available with mechanical controls or Digital Throttle \u0026amp; Shift (DTS) on some rigs.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eTypical 175–225 HP four‑stroke V6 families, including commercial\/SeaPro variants in some markets.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eSmooth operation and broad torque; straightforward annual service (oil\/filter, gear lube, impeller).\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 oil filter, spark plug type, and gearcase parts by serial number; many components interchange within 175–225 HP families but always verify.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\n  \u003ch3\u003eInline‑6 Supercharged (approx. 200–400 HP)\u003c\/h3\u003e\n  \u003ctable style=\"width:100%; border-collapse:collapse; margin-top:10px;\"\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;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eFour‑stroke inline‑6 with supercharger; commonly paired with DTS and integrated\/electric‑hydraulic power steering.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003e200–400 HP inline‑6 supercharged platforms; multiple midsection\/steering options exist.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eRefined NVH with strong mid‑range and top‑end performance.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eFilters, anodes, intake, and steering\/DTS parts are platform‑specific. Verify by model\/serial and steering type.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\n  \u003ch3\u003eV8 Four‑Stroke (approx. 250–430 HP)\u003c\/h3\u003e\n  \u003ctable style=\"width:100%; border-collapse:collapse; margin-top:10px;\"\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;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eFour‑stroke V8, EFI; many models feature DTS and advanced midsection\/steering systems.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eHigh‑output 250–430 HP four‑stroke families for performance and heavy‑duty applications.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eHigh thrust and top speed potential with robust charging systems and cooling capacity.\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 oil capacity, filter style, and gearcase type (standard, heavy‑duty, or performance) before ordering service parts.\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:20px 0; max-width:1100px;\"\u003e\n  \u003ch2\u003eRoutine Maintenance \u0026amp; Service Parts\u003c\/h2\u003e\n  \u003cp\u003eIntervals below are general guidelines for many 4‑stroke outboards. Always follow the procedures and specifications in your official service manual and verify parts by 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; 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;\"\u003eEngine oil \u0026amp; filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eUse marine‑rated oil; replace drain plug washer if specified.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-oil-filters\"\u003eMerCruiser Oil Filters\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eGear oil (lower unit)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eInspect for water or metal; replace drain\/fill seals when servicing.\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      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eSpark plugs\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eEvery 300 hours or 3 years\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eCheck gap and condition; replace sooner for misfire or fouling.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\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;\"\u003eFuel filter \/ water separator\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eDrain water (if equipped) and replace element; monitor fuel quality.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-fuel-filters\"\u003eMerCruiser Fuel Filters\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eWater pump impeller\/kit\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eEvery 2–3 seasons (≈200 hours)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eService sooner for weak tell‑tale, overheat alarms, or sandy\/silty operation.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\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;\"\u003eAnodes (sacrificial)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eInspect every 50 hours; replace at ~50% wear\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eMatch material to water type (aluminum, zinc, magnesium) and keep clean.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/anodes\"\u003eAnodes\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"common-parts\" style=\"padding:20px 0; max-width:1100px;\"\u003e\n  \u003ch2\u003eFrequently Used Parts Categories\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eRoutine Service — \u003ca href=\"https:\/\/seasierra.com\/collections\/service-maintenance-kits\"\u003eService \u0026amp; Maintenance Kits\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCooling System — \u003ca href=\"https:\/\/seasierra.com\/collections\/water-pump-impeller-rebuild-kits\"\u003eWater Pump Impeller Rebuild Kits\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eFuel System — \u003ca href=\"https:\/\/seasierra.com\/collections\/fuel-filters-1\"\u003eFuel Filters\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eIgnition \/ Electrical — \u003ca href=\"https:\/\/seasierra.com\/collections\/electrical-items\"\u003eElectrical Items\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003ePropulsion — \u003ca href=\"https:\/\/seasierra.com\/collections\/propellers\"\u003ePropellers\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCorrosion Protection — \u003ca href=\"https:\/\/seasierra.com\/collections\/anodes\"\u003eAnodes\u003c\/a\u003e\n\u003c\/li\u003e\n    \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  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"troubleshooting\" style=\"padding:20px 0; max-width:1100px;\"\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;\"\u003eWeak tell‑tale \/ overheat alarm\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eInspect intake screens, flush passages, verify thermostat operation, and check impeller condition.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eWater pump kit, thermostat, intake screen, anodes\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003ePoor acceleration \/ power loss\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eCheck prop condition\/pitch, fuel quality, clogged filters, and spark plug condition.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003ePropeller, fuel filter, spark plugs, fuel injectors\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eHard starting \/ rough idle\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eVerify battery voltage, prime the system, and inspect air path\/IAC for deposits.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eSpark plugs, fuel filter, electrical items\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;\"\u003eDrain and inspect gear lube; check for water intrusion and propshaft seal damage (e.g., fishing line).\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eLower unit seal kit, bearings, propeller\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eTrim\/tilt won’t hold\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eCheck fluid level, look for external leaks, and verify trim motor operation.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eTrim motor, seals\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:20px 0; max-width:1100px;\"\u003e\n  \u003ch2\u003eFAQs\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eAre parts interchangeable between different years or platforms?\u003c\/summary\u003e\n    \u003cp\u003eNot always. V6 EFI, inline‑6 supercharged, and V8 platforms use different filters, anodes, cooling, and control\/steering components. Confirm by serial number, platform, and model year before ordering.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhen should the impeller be replaced?\u003c\/summary\u003e\n    \u003cp\u003eAs a rule of thumb, service the water pump every 2–3 seasons (about 200 hours), or immediately if the tell‑tale weakens or any overheat alarms occur. Gritty or sandy water may require more frequent service.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow often should gear oil be changed?\u003c\/summary\u003e\n    \u003cp\u003eTypically every 100 hours or annually. If you find milky lube, metal debris, or a low level, inspect seals and bearings right away.\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 complete model and serial number, shaft length, control type (mechanical or DTS), and the system you’re servicing (cooling, fuel, ignition, gearcase). Photos of the nameplate and the part to be replaced also help.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"cta\" style=\"padding:16px; border:1px solid #e5e7eb; border-radius:8px; max-width:1100px;\"\u003e\n  \u003cp\u003eReady to find parts by horsepower, year, and model? Browse the main MerCruiser collection and refine with the filters to locate compatible components for your 4‑stroke outboard.\u003c\/p\u003e\n  \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser\" style=\"display:inline-block; padding:10px 16px; background:#0a4; color:#fff; text-decoration:none; border-radius:6px;\"\u003eShop MerCruiser Parts\u003c\/a\u003e\n  \u003cp style=\"margin-top:8px; 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":[{"product_id":"closed-riser-gasket-fits-mercruiser-gm-v6-v8-5-0l-8-2l-replaces-27-8637251-27-860231","title":"Closed Center-Riser Exhaust Manifold Gasket for MerCruiser GM V6\/V8 – Replaces 27-8637251, 27-860231","description":"\u003c!-- 🔧 Table Styles (include only once per page) --\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 {\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 \u003cstrong\u003eclosed center-riser exhaust manifold gasket\u003c\/strong\u003e is an aftermarket replacement for selected MerCruiser stern-drive and inboard applications using General Motors V6 and V8 engines with a MerCruiser closed-cooling system. It is intended for center-exit exhaust manifolds and closed riser connections.\u003c\/p\u003e\n  \u003cp\u003eThe company application data identifies this gasket for wet-joint configurations on GM 229\/262 CID V6 engines, GM 305\/350\/377 CID small-block V8 engines, and GM 454\/502 CID big-block V8 engines. The same gasket is also listed as a dry-joint alternative for applicable GM V6\/V8 small-block installations. Confirm the joint design, cooling-system type, engine configuration, and original gasket number before ordering.\u003c\/p\u003e\n  \u003cul\u003e\n    \u003cli\u003e\n\u003cstrong\u003eProduct type:\u003c\/strong\u003e Exhaust manifold-to-riser gasket\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eRiser style:\u003c\/strong\u003e Center riser, closed or block-off design\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eCooling system:\u003c\/strong\u003e MerCruiser closed cooling \/ fresh-water cooling system\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eJoint configurations:\u003c\/strong\u003e Wet joint; dry-joint alternative where the original application specifies it\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eQuantity:\u003c\/strong\u003e One gasket\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n  \u003cp\u003eThe following manufacturer and aftermarket references are listed for identification and cross-reference purposes. They do not replace confirmation of the complete engine and exhaust configuration.\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 number\u003c\/th\u003e\n\u003c\/tr\u003e\n      \u003c\/thead\u003e\n      \u003ctbody\u003e\n        \u003ctr\u003e\n\u003ctd\u003eMercury MerCruiser\u003c\/td\u003e\n\u003ctd\u003e27-8637251\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eMercury MerCruiser\u003c\/td\u003e\n\u003ctd\u003e27-863725\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eMercury MerCruiser\u003c\/td\u003e\n\u003ctd\u003e27-860231\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eMercury MerCruiser\u003c\/td\u003e\n\u003ctd\u003e27-41811\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eGLM\u003c\/td\u003e\n\u003ctd\u003e30220\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eMallory\u003c\/td\u003e\n\u003ctd\u003e9-61422\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-0672\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-0672-9\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eOMC\u003c\/td\u003e\n\u003ctd\u003e0502988\u003c\/td\u003e\n\u003c\/tr\u003e\n        \u003ctr\u003e\n\u003ctd\u003eOMC\u003c\/td\u003e\n\u003ctd\u003e0508715\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 and Application Compatibility\u003c\/h2\u003e\n  \u003cp\u003eCompany fitment data groups this gasket by engine family and exhaust-joint design rather than by a single universal model list. Keep the engine family, horsepower range, joint type, cooling-system type, and serial-number condition together when confirming fitment.\u003c\/p\u003e\n  \u003cdiv class=\"ss-table-wrap\"\u003e\n    \u003ctable class=\"ss-table\" aria-label=\"Engine and Application Compatibility\"\u003e\n      \u003cthead\u003e\n        \u003ctr\u003e\n          \u003cth\u003eEngine application\u003c\/th\u003e\n          \u003cth\u003eEngine family\u003c\/th\u003e\n          \u003cth\u003eJoint configuration\u003c\/th\u003e\n          \u003cth\u003eCooling system\u003c\/th\u003e\n          \u003cth\u003eApplication notes\u003c\/th\u003e\n        \u003c\/tr\u003e\n      \u003c\/thead\u003e\n      \u003ctbody\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eMerCruiser 175–205\u003c\/td\u003e\n          \u003ctd\u003eV6, GM 229\/262 CID\u003c\/td\u003e\n          \u003ctd\u003eWet joint\u003c\/td\u003e\n          \u003ctd\u003eClosed cooling\u003c\/td\u003e\n          \u003ctd\u003eCenter-riser exhaust manifold application; serial condition listed by the company as 1983 through 0M serial numbers.\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eMerCruiser 200–320\u003c\/td\u003e\n          \u003ctd\u003eV8 small-block, GM 305\/350\/377 CID\u003c\/td\u003e\n          \u003ctd\u003eWet joint\u003c\/td\u003e\n          \u003ctd\u003eClosed cooling\u003c\/td\u003e\n          \u003ctd\u003eCenter-riser exhaust manifold application; serial condition listed by the company as 1983 through 0M serial numbers.\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eMerCruiser 330–370\u003c\/td\u003e\n          \u003ctd\u003eV8 big-block, GM 454\/502 CID\u003c\/td\u003e\n          \u003ctd\u003eWet joint\u003c\/td\u003e\n          \u003ctd\u003eClosed cooling\u003c\/td\u003e\n          \u003ctd\u003eCenter-riser exhaust manifold application; serial condition listed by the company as 1981 and up.\u003c\/td\u003e\n        \u003c\/tr\u003e\n        \u003ctr\u003e\n          \u003ctd\u003eApplicable GM V6\/V8 small-block applications\u003c\/td\u003e\n          \u003ctd\u003eGM V6\/V8 small-block\u003c\/td\u003e\n          \u003ctd\u003eDry-joint alternative\u003c\/td\u003e\n          \u003ctd\u003eVerify system configuration\u003c\/td\u003e\n          \u003ctd\u003eUse only where the original application specifies this gasket as the dry-joint alternative; serial condition listed by the company as 0M serial numbers and up.\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 Specifications\u003c\/h2\u003e\n  \u003cdl\u003e\n    \u003cdt\u003eProduct type\u003c\/dt\u003e\n    \u003cdd\u003eExhaust manifold-to-riser gasket\u003c\/dd\u003e\n    \u003cdt\u003eRiser design\u003c\/dt\u003e\n    \u003cdd\u003eCenter riser, closed or block-off style\u003c\/dd\u003e\n    \u003cdt\u003eCooling-system application\u003c\/dt\u003e\n    \u003cdd\u003eMerCruiser closed cooling \/ fresh-water cooling system\u003c\/dd\u003e\n    \u003cdt\u003eJoint application\u003c\/dt\u003e\n    \u003cdd\u003eWet joint; dry-joint alternative for specified GM V6\/V8 small-block applications\u003c\/dd\u003e\n    \u003cdt\u003eReplacement status\u003c\/dt\u003e\n    \u003cdd\u003eAftermarket replacement; not an OEM component\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\u003e\n\u003cspan style=\"color:#d0021b;\"\u003e1 x\u003c\/span\u003e Closed center-riser exhaust manifold gasket\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n  \u003col\u003e\n    \u003cli\u003eAllow the engine to cool completely and disconnect the battery before beginning service.\u003c\/li\u003e\n    \u003cli\u003eIdentify the cooling-system arrangement and drain the relevant section as required by the service manual.\u003c\/li\u003e\n    \u003cli\u003eRemove the riser or exhaust-manifold connection and record bolt locations and hardware condition.\u003c\/li\u003e\n    \u003cli\u003eRemove the old gasket and thoroughly clean both mating surfaces. Remove gasket residue, rust, scale, and debris without damaging the sealing faces.\u003c\/li\u003e\n    \u003cli\u003eCompare the new gasket with the removed gasket and verify the port pattern, bolt holes, and closed-riser design.\u003c\/li\u003e\n    \u003cli\u003eInstall the gasket in the correct orientation and refit the riser or manifold.\u003c\/li\u003e\n    \u003cli\u003eTighten the fasteners in the manufacturer-specified sequence and to the torque stated in the applicable service manual. Do not guess the torque value.\u003c\/li\u003e\n    \u003cli\u003eRestore the cooling system, reconnect the battery, and run the engine only after all required components and fluids have been reinstalled.\u003c\/li\u003e\n    \u003cli\u003eInspect the connection for coolant, water, or exhaust leaks after startup and again after the engine reaches operating temperature.\u003c\/li\u003e\n  \u003c\/ol\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eTroubleshooting and FAQ\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eIs this an open or closed riser gasket?\u003c\/summary\u003e\n    \u003cp\u003eThis is a \u003cstrong\u003eclosed center-riser, block-off-style gasket\u003c\/strong\u003e. It is listed for MerCruiser closed-cooling applications. Do not substitute an open gasket unless it matches the original engine and exhaust configuration.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eDoes this listing include two gaskets?\u003c\/summary\u003e\n    \u003cp\u003eNo. This listing is for \u003cstrong\u003eone gasket\u003c\/strong\u003e. A separate company record exists for a two-piece package, but that package is not the same product quantity as this single-gasket listing.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWill it fit every MerCruiser V6 or V8 engine?\u003c\/summary\u003e\n    \u003cp\u003eNo. The listed applications are limited to specified GM V6 and V8 engine families with the matching center-riser, closed-cooling configuration. Verify the original gasket number, joint style, cooling system, and engine serial condition before ordering.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhat are common signs of a failed riser gasket?\u003c\/summary\u003e\n    \u003cp\u003ePossible symptoms include coolant or water leakage at the manifold-to-riser joint, exhaust leakage, corrosion or staining around the mating surfaces, overheating, or water entering areas where it should not. Diagnose the complete exhaust and cooling system before replacing the gasket.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eShould gasket sealant be used?\u003c\/summary\u003e\n    \u003cp\u003eUse the installation method specified by the applicable engine or exhaust-manifold service manual. Do not apply sealant unless the gasket manufacturer or service procedure calls for it, because excess sealant can obstruct cooling or exhaust passages.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eIs this an OEM gasket?\u003c\/summary\u003e\n    \u003cp\u003eNo. This is an aftermarket replacement gasket. The numbers shown in the part-number matrix are manufacturer, aftermarket, or cross-reference identifiers used to help verify the application.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n  \u003ch2\u003eSafety and Important Information\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eVerify the original gasket number and physical port pattern before purchase.\u003c\/li\u003e\n    \u003cli\u003eConfirm that your engine uses the closed-cooling system and the applicable center-riser configuration.\u003c\/li\u003e\n    \u003cli\u003eDo not use an open gasket in place of a closed gasket, or a wet-joint gasket in place of a dry-joint gasket, unless the service documentation specifically confirms the substitution.\u003c\/li\u003e\n    \u003cli\u003eFollow the engine manufacturer's torque sequence and service instructions.\u003c\/li\u003e\n    \u003cli\u003eProfessional installation is recommended when servicing exhaust manifolds, risers, or closed-cooling systems.\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 components for common marine propulsion and exhaust-system service applications.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eApplication-focused listings\u003c\/strong\u003e — Product descriptions identify cooling-system, joint-style, engine-family, and reference-number conditions where available.\u003c\/li\u003e\n    \u003cli\u003e\n\u003cstrong\u003eSupport for fitment checks\u003c\/strong\u003e — Compare your original part number and configuration before ordering to help ensure the correct replacement.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50723788587323,"sku":"23GT297","price":13.75,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/2PCS_Closed_Riser_Gasket_for_MerCruiser_GM_V6_and_V8_50L-82L_Stern_Drive___________27-8637251_-_JLM_MARINE-8287550.jpg?v=1763031790"}],"url":"https:\/\/seasierra.com\/collections\/mercruiser-4-stroke-outboard-marine-engine-parts-175-430hp.oembed","provider":"SeaSierra","version":"1.0","type":"link"}