{"title":"MerCruiser 4-Stroke 165-190HP Marine Engine Parts","description":"\u003csection id=\"hero\" style=\"padding:16px;border:1px solid #e5e7eb;border-radius:8px;\"\u003e\n  \u003cp\u003e\n    This page is dedicated to MerCruiser 4‑Stroke 165–190 HP sterndrive engines. Use it to quickly find compatible parts and practical service information. Below you’ll find maintenance tips, common replacement parts, and troubleshooting guidance. You can also browse our main MerCruiser 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.\n  \u003c\/p\u003e\n  \u003cp\u003e\n    \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser\" style=\"display:inline-block;padding:10px 14px;background:#0ea5e9;color:#fff;text-decoration:none;border-radius:6px;\"\u003eBrowse All MerCruiser Parts\u003c\/a\u003e\n  \u003c\/p\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"identify-model\" style=\"padding:16px;\"\u003e\n  \u003ch2\u003eHow to Identify Your 165–190 HP Model\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eLocate the serial number plate: typically on the flame arrestor\/engine cover decal, on the engine block, and on the transom assembly and sterndrive unit (Alpha or Bravo).\u003c\/li\u003e\n    \u003cli\u003eRead model\/serial details and suffixes: these indicate drive type (Alpha One Gen I\/Gen II vs Bravo), gear ratio, and build year or revision.\u003c\/li\u003e\n    \u003cli\u003eDistinguish platforms: the 4.3L V6 (190 HP) has six spark plugs and a V‑bank layout; the older 3.7L inline‑4 (often 165–190 HP “470” family) has four spark plugs and a longitudinal inline layout.\u003c\/li\u003e\n    \u003cli\u003eConfirm control\/rigging options (carb vs EFI, raw‑water vs seawater pump variants) before ordering service parts.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"engine-overview\" style=\"padding:16px;\"\u003e\n  \u003ch2\u003ePlatform Overview\u003c\/h2\u003e\n  \u003ch3\u003e4.3L V6 (Approx. 190 HP)\u003c\/h3\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse;max-width:980px;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eDescription\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eV6 4‑stroke petrol, typically carbureted or EFI, mated to Alpha or Bravo drives.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eMerCruiser 4.3L (190 HP) Alpha\/Bravo configurations.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eProven reliability, good torque for holeshot, broad parts availability.\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 fuel system (carb vs EFI) and cooling layout; service items (plugs, filters, impeller) are platform‑specific.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\n  \u003ch3\u003e3.7L Inline‑4 (Approx. 165–190 HP “470” Family)\u003c\/h3\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse;max-width:980px;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eFeature\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eDescription\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eConfiguration\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eInline‑4 4‑stroke petrol, commonly paired with Alpha drives; unique charging\/cooling components on many variants.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eCommon Models\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eMerCruiser 165\/170\/180\/190 HP “470\/488\/190” family.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eAdvantages\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eCompact, strong low‑to‑mid range torque, widely supported with service parts.\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eNotes\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003ePay attention to charging and cooling components when ordering; verify serial numbers due to running changes across years.\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"service-kits\" style=\"padding:16px;\"\u003e\n  \u003ch2\u003eRoutine Maintenance \u0026amp; Service Parts\u003c\/h2\u003e\n  \u003cp\u003eIntervals below are general guidelines for typical recreational use. Always follow your official MerCruiser service manual for the exact schedule for your engine\/drive.\u003c\/p\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse;max-width:980px;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eItem\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eInterval*\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eRemarks\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eParts Link\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eEngine oil + filter\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eWarm the engine before draining; replace crush washer if applicable.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\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;border-bottom:1px solid #f3f4f6;\"\u003eGear oil (drive)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eChange from bottom drain; inspect for water or metal sheen; replace seals if needed.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser\"\u003eMerCruiser Collection\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eSpark plugs\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eInspect 100 hours; replace 200–300 hours\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eSet gap to spec; check leads and cap\/rotor (if equipped).\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\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 #f3f4f6;\"\u003eFuel filter \/ water separator\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eDrain and inspect for water; replace canister element or inline filter.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\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;border-bottom:1px solid #f3f4f6;\"\u003eRaw water pump impeller\/kit\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eEvery 2 seasons (or sooner in sandy\/silty water)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eReplace housing and wear plate if scored; verify seawater hose condition.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-impellers\"\u003eMerCruiser Impellers\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eAnodes (zinc\/aluminum\/magnesium)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eInspect monthly; replace when 50% consumed\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eMatch material to water type (salt\/brackish\/fresh); clean contact areas.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-anodes\"\u003eMerCruiser Anodes\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eThermostat inspection\/replacement\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eInspect annually; replace 2–3 years\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eIf running cool\/hot or with uneven temps, test thermostat and sender.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser\"\u003eMerCruiser Collection\u003c\/a\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"common-parts\" style=\"padding:16px;\"\u003e\n  \u003ch2\u003eFrequently Used Parts Categories\u003c\/h2\u003e\n  \u003cul\u003e\n    \u003cli\u003eRoutine Service Kits – \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-service-maintenance-kits\"\u003eMerCruiser Service \u0026amp; Maintenance Kits\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCooling System – \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-impellers\"\u003eMerCruiser Impellers\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eFuel System – \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-fuel-filters\"\u003eMerCruiser Fuel Filters\u003c\/a\u003e and \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-fuel-pumps\"\u003eMerCruiser Fuel Pumps\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eIgnition \/ Electrical – \u003ca href=\"https:\/\/seasierra.com\/collections\/electrical-items\"\u003eElectrical Items\u003c\/a\u003e and \u003ca href=\"https:\/\/seasierra.com\/collections\/spark-plug\"\u003eSpark Plugs\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003ePropulsion – \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-propellers\"\u003eMerCruiser Propellers\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eCorrosion Protection – \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-anodes\"\u003eMerCruiser Anodes\u003c\/a\u003e\n\u003c\/li\u003e\n    \u003cli\u003eGaskets \u0026amp; Sealing – \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-gaskets\"\u003eMerCruiser Gaskets\u003c\/a\u003e and \u003ca href=\"https:\/\/seasierra.com\/collections\/lower-unit-seal-kits\"\u003eLower 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:16px;\"\u003e\n  \u003ch2\u003eCommon Symptoms \u0026amp; Quick Checks\u003c\/h2\u003e\n  \u003ctable style=\"width:100%;border-collapse:collapse;max-width:980px;\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eSymptom\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eCheck First\u003c\/th\u003e\n        \u003cth style=\"text-align:left;border-bottom:1px solid #e5e7eb;padding:8px;\"\u003eRelated Parts\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eOverheat alarm \/ high temp\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eInspect seawater intake screens, hoses, belt tension, and raw‑water impeller; verify thermostat operation.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eWater pump impeller kit, thermostat, intake screen, belts\/hoses\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003ePoor acceleration \/ power loss\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eCheck fuel quality, water separator, spark plugs, prop damage or incorrect pitch; verify throttle linkage.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eFuel filter, spark plugs, fuel pump, propeller\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eHard starting \/ rough idle\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eInspect plugs, ignition components, idle air control (EFI) or idle circuits (carb); verify no vacuum leaks.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eSpark plugs, plug wires\/cap, fuel filter, IAC valve (EFI)\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eGearcase noise \/ metal in gear oil\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eDrain oil and inspect; check prop shaft for fishing line; pressure test for leaking seals; verify gear lash.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;border-bottom:1px solid #f3f4f6;\"\u003eLower unit seal kit, bearings, shims, gear lube\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd style=\"padding:8px;\"\u003eCharging system fault (3.7L family)\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eTest battery, regulator\/rectifier, and stator\/alternator system; inspect grounds and connectors.\u003c\/td\u003e\n        \u003ctd style=\"padding:8px;\"\u003eRegulator\/rectifier, stator\/alternator components, 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;\"\u003e\n  \u003ch2\u003eFAQs\u003c\/h2\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eAre parts interchangeable between different years or platforms (V6 vs 3.7L inline‑4)?\u003c\/summary\u003e\n    \u003cp\u003eMany items are platform‑specific. Filters, ignition parts, water pump kits, and gaskets can differ between 4.3L V6 and 3.7L inline‑4 engines, and by drive type (Alpha vs Bravo). Always verify by serial numbers before ordering.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eWhen should I replace the raw‑water impeller?\u003c\/summary\u003e\n    \u003cp\u003eInspect annually and replace every two seasons for typical use, or sooner if you operate in sandy\/silty water or see any signs of overheating or reduced cooling flow.\u003c\/p\u003e\n  \u003c\/details\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003eHow often should sterndrive gear oil be changed?\u003c\/summary\u003e\n    \u003cp\u003eChange gear oil every 100 hours or at least once per year. Inspect for water intrusion or metal debris and address seal or bearing issues if found.\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 engine serial number, sterndrive (Alpha\/Bravo) serial number, transom assembly serial number, fuel system type (carb\/EFI), and any key measurements (e.g., gear ratio) noted on your tags or manual.\u003c\/p\u003e\n  \u003c\/details\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"cta\" style=\"padding:16px;border-top:1px solid #e5e7eb;\"\u003e\n  \u003cp\u003eReady to find parts? Browse the main MerCruiser collection and use the filters to narrow by horsepower, year, and model.\u003c\/p\u003e\n  \u003cp\u003e\n    \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser\" style=\"display:inline-block;padding:10px 14px;background:#0ea5e9;color:#fff;text-decoration:none;border-radius:6px;\"\u003eShop MerCruiser Parts\u003c\/a\u003e\n  \u003c\/p\u003e\n  \u003cp style=\"color:#4b5563;\"\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":"thermostat-kit-160-f-71-c-fits-mercruiser-3-7l-4-cylinder-engines-replaces-99155t1-99155t2","title":"160°F Thermostat Service Kit for MerCruiser Built 4-Cylinder Engines, 1976–1982 – Excludes 470","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 aftermarket \u003cstrong\u003e160°F (71°C) thermostat service kit\u003c\/strong\u003e is intended for MerCruiser-built 4-cylinder marine engines that are not Chevrolet-based, with applications from 1976 through 1982. It is designed for the applicable MerCruiser stern-drive and out-drive cooling systems described below.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eImportant fitment limitation:\u003c\/strong\u003e this kit does \u003cstrong\u003enot\u003c\/strong\u003e fit the MerCruiser 470 engine. Confirm that your engine is a non-Chevrolet MerCruiser-built 4-cylinder model and that the year and thermostat-housing configuration match before ordering.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e160°F (71°C) thermostat for the specified marine engine applications.\u003c\/li\u003e\n\u003cli\u003eService-kit configuration with the thermostat, rubber ring, and gasket listed below.\u003c\/li\u003e\n\u003cli\u003eUseful replacement references include MerCruiser part numbers 27-74830, 27-896561, 76270T, 991551, 99155A1, 99155T1, and 99155T2.\u003c\/li\u003e\n\u003cli\u003eAftermarket replacement; verify the original part, housing, and reference numbers before installation.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n\u003cp\u003eThe following numbers are manufacturer or aftermarket reference numbers associated with this product. They are provided for identification and cross-reference purposes only; confirm physical compatibility before installation.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Part Number Cross-Reference\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eBrand or Source\u003c\/th\u003e\n        \u003cth\u003ePart Number\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\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003e27-74830\u003c\/td\u003e\n\u003ctd\u003eListed manufacturer reference.\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003e27-896561\u003c\/td\u003e\n\u003ctd\u003eListed manufacturer reference.\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003e76270T\u003c\/td\u003e\n\u003ctd\u003eListed manufacturer reference.\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003e991551\u003c\/td\u003e\n\u003ctd\u003eListed manufacturer reference.\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003e99155A1\u003c\/td\u003e\n\u003ctd\u003eThermostat reference for the included thermostat.\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003e99155T1\u003c\/td\u003e\n\u003ctd\u003eListed manufacturer reference.\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eMerCruiser\u003c\/td\u003e\n\u003ctd\u003e99155T2\u003c\/td\u003e\n\u003ctd\u003eListed manufacturer reference.\u003c\/td\u003e\n\u003c\/tr\u003e\n      \u003ctr\u003e\n\u003ctd\u003eSierra\u003c\/td\u003e\n\u003ctd\u003e18-3555\u003c\/td\u003e\n\u003ctd\u003eListed aftermarket reference.\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\u003ch2\u003eEngine \u0026amp; Model Compatibility\u003c\/h2\u003e\n\u003cp\u003eUse the combined engine construction, cylinder count, year range, and exclusion below when checking fitment. The supplied product data does not establish compatibility with every individual model designation within this range.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Compatible MerCruiser Engine Conditions\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eBrand\u003c\/th\u003e\n        \u003cth\u003eEngine Construction\u003c\/th\u003e\n        \u003cth\u003eCylinders\u003c\/th\u003e\n        \u003cth\u003eYears\u003c\/th\u003e\n        \u003cth\u003eExclusion\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMerCruiser\u003c\/td\u003e\n        \u003ctd\u003eMerCruiser-built, non-Chevrolet engine\u003c\/td\u003e\n        \u003ctd\u003e4-cylinder\u003c\/td\u003e\n        \u003ctd\u003e1976–1982\u003c\/td\u003e\n        \u003ctd\u003eDoes not fit MerCruiser 470\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\u003ch2\u003eTechnical Specs\u003c\/h2\u003e\n\u003cdl\u003e\n  \u003cdt\u003eProduct Type\u003c\/dt\u003e\n  \u003cdd\u003eMarine engine thermostat service kit\u003c\/dd\u003e\n  \u003cdt\u003eThermostat Rating\u003c\/dt\u003e\n  \u003cdd\u003e160°F (71°C)\u003c\/dd\u003e\n  \u003cdt\u003eApplication\u003c\/dt\u003e\n  \u003cdd\u003eMerCruiser-built, non-Chevrolet 4-cylinder marine engines\u003c\/dd\u003e\n  \u003cdt\u003eApplication Years\u003c\/dt\u003e\n  \u003cdd\u003e1976–1982\u003c\/dd\u003e\n  \u003cdt\u003eEngine Exclusion\u003c\/dt\u003e\n  \u003cdd\u003eMerCruiser 470\u003c\/dd\u003e\n  \u003cdt\u003eInstallation\u003c\/dt\u003e\n  \u003cdd\u003eReplacement installation using the applicable thermostat housing procedure\u003c\/dd\u003e\n\u003c\/dl\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 Thermostat, reference 99155A1\u003c\/li\u003e\n  \u003cli\u003e\n\u003cspan style=\"color:#d0021b;\"\u003e1 x\u003c\/span\u003e Rubber ring\u003c\/li\u003e\n  \u003cli\u003e\n\u003cspan style=\"color:#d0021b;\"\u003e1 x\u003c\/span\u003e Gasket, reference 27-33918\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n  \u003cli\u003eAllow the engine to cool completely before beginning service.\u003c\/li\u003e\n  \u003cli\u003eConfirm the engine is a MerCruiser-built, non-Chevrolet 4-cylinder application from 1976–1982 and is not a MerCruiser 470.\u003c\/li\u003e\n  \u003cli\u003eDrain coolant as necessary to prevent spills when opening the thermostat housing.\u003c\/li\u003e\n  \u003cli\u003eRemove the thermostat housing and note the original thermostat and seal orientation.\u003c\/li\u003e\n  \u003cli\u003eClean the mating surfaces carefully without damaging the housing or manifold.\u003c\/li\u003e\n  \u003cli\u003eInstall the thermostat, rubber ring, and gasket in the correct position for your housing.\u003c\/li\u003e\n  \u003cli\u003eReinstall the housing and tighten the fasteners according to the engine manufacturer’s service procedure.\u003c\/li\u003e\n  \u003cli\u003eRefill the cooling system with the specified coolant, run the engine, and inspect the housing for leaks.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow do I know if this thermostat kit fits my engine?\u003c\/summary\u003e\n  \u003cp\u003eCheck all fitment conditions together: the engine must be MerCruiser-built, non-Chevrolet, 4-cylinder, and from 1976–1982. This kit specifically excludes the MerCruiser 470. Compare the thermostat, housing, and reference numbers with your original parts before installation.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat is the thermostat opening temperature?\u003c\/summary\u003e\n  \u003cp\u003eThe thermostat is rated at 160°F (71°C).\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat parts are included?\u003c\/summary\u003e\n  \u003cp\u003eThe service kit includes one 160°F thermostat, one rubber ring, and one gasket identified by reference 27-33918.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhich reference numbers are associated with this kit?\u003c\/summary\u003e\n  \u003cp\u003eListed references include MerCruiser 27-74830, 27-896561, 76270T, 991551, 99155A1, 99155T1, and 99155T2, plus aftermarket reference 18-3555. Reference numbers alone do not replace the need to verify the complete engine and housing application.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eIs this an OEM component?\u003c\/summary\u003e\n  \u003cp\u003eNo. This is an aftermarket replacement service kit. MerCruiser and aftermarket part numbers are shown only as product-identification and cross-reference information.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003ch2\u003eSafety \u0026amp; Important Info\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eWork only on a completely cool engine and follow the appropriate marine-engine service procedure.\u003c\/li\u003e\n  \u003cli\u003eDo not use this kit for a MerCruiser 470 engine.\u003c\/li\u003e\n  \u003cli\u003eVerify engine construction, cylinder count, year, thermostat housing, and original part appearance before purchase.\u003c\/li\u003e\n  \u003cli\u003eProfessional installation is recommended if you are unsure about the cooling-system service procedure.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMarine Parts Support\u003c\/strong\u003e — We provide replacement components for marine service and repair applications.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eApplication-Focused Listings\u003c\/strong\u003e — Product information is organized around engine, year, and component-reference details.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eReplacement Value\u003c\/strong\u003e — Aftermarket options help support practical maintenance and repair needs.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50723786654011,"sku":"23TH636","price":31.9,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/Thermostat_Repair_Service_Kit_for_Mercruiser_4_Cyl_37L_SternDrive_Motors__99155T1_-_JLM_MARINE-8286934.jpg?v=1763031734"},{"product_id":"exhaust-elbow-gasket-fits-mercruiser-3-7l-165-190hp-replaces-27-18272-27-97863","title":"Exhaust Elbow Gasket for MerCruiser 3.7L 4-Cylinder 170\/470 (1985–1989) – Replaces 27-18272, 27-97863","description":"\u003cstyle\u003e\n  \/* Outer container allows horizontal scrolling (with iOS momentum) *\/\n  .ss-table-wrap { overflow-x:auto; -webkit-overflow-scrolling:touch; }\n\n  \/* Base table styles *\/\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\n  \/* Key: prevent wrapping, word breaks, and vertical text in headers *\/\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\n  \/* Small screen optimization *\/\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 direct-replacement \u003cstrong\u003eExhaust Elbow Gasket\u003c\/strong\u003e is designed for MerCruiser 3.7L 4-cylinder 170 and 470 engines with aluminum exhaust manifolds from 1985–1989. It seals the mounting connection between the exhaust elbow and manifold when the elbow is installed or serviced.\u003c\/p\u003e\n\u003cp\u003eThis is a single gasket, not a complete mounting kit. The gasket is listed as a replacement for MerCruiser reference numbers 27-18272 and 27-97863.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eDirect-fit exhaust elbow mounting gasket for specified MerCruiser applications.\u003c\/li\u003e\n\u003cli\u003eHelps seal the elbow-to-manifold joint and prevent exhaust or cooling-water leakage at the connection.\u003c\/li\u003e\n\u003cli\u003eSuitable for the aluminum-manifold applications identified below.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n\u003cp\u003eUse these manufacturer and aftermarket references to compare your existing gasket before ordering.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Part Number Matrix\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eBrand\u003c\/th\u003e\n        \u003cth\u003ePart Number\u003c\/th\u003e\n      \u003c\/tr\u003e\n    \u003c\/thead\u003e\n    \u003ctbody\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMerCruiser\u003c\/td\u003e\n        \u003ctd\u003e27-18272\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMerCruiser\u003c\/td\u003e\n        \u003ctd\u003e27-97863\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMerCruiser\u003c\/td\u003e\n        \u003ctd\u003e18272 \/ 97863\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eGLM\u003c\/td\u003e\n        \u003ctd\u003e32470\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eSierra\u003c\/td\u003e\n        \u003ctd\u003e18-0881 \/ 18-0881-1\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMallory\u003c\/td\u003e\n        \u003ctd\u003e9-61412\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eOMC\u003c\/td\u003e\n        \u003ctd\u003e0508753\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eEngine \u0026amp; Model Compatibility\u003c\/h2\u003e\n\u003cp\u003eConfirm the engine model, manifold construction, and model year before ordering. The fitment information for this gasket should be kept together because the aluminum-manifold condition is part of the application.\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\u003eEngine \/ Model\u003c\/th\u003e\n        \u003cth\u003eDisplacement\u003c\/th\u003e\n        \u003cth\u003eRated Model\u003c\/th\u003e\n        \u003cth\u003eStroke\u003c\/th\u003e\n        \u003cth\u003eYears\u003c\/th\u003e\n        \u003cth\u003eManifold Condition\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\u003eMerCruiser\u003c\/td\u003e\n        \u003ctd\u003e170 \/ 470, 4-cylinder\u003c\/td\u003e\n        \u003ctd\u003e3.7L\u003c\/td\u003e\n        \u003ctd\u003e170 \/ 470\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1985–1989\u003c\/td\u003e\n        \u003ctd\u003eAluminum exhaust manifold\u003c\/td\u003e\n        \u003ctd\u003e27-18272, 27-97863\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMerCruiser\u003c\/td\u003e\n        \u003ctd\u003e4-cylinder applications\u003c\/td\u003e\n        \u003ctd\u003e3.7L\u003c\/td\u003e\n        \u003ctd\u003e470\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003eNot applicable to 1976–1982 470 cast-iron-manifold applications\u003c\/td\u003e\n        \u003ctd\u003eVerify aluminum manifold; cast-iron applications are excluded where noted\u003c\/td\u003e\n        \u003ctd\u003e27-18272, 27-97863\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eTechnical Specs\u003c\/h2\u003e\n\u003cdl\u003e\n  \u003cdt\u003eProduct Type\u003c\/dt\u003e\n  \u003cdd\u003eExhaust elbow gasket\u003c\/dd\u003e\n  \u003cdt\u003eQuantity\u003c\/dt\u003e\n  \u003cdd\u003e1 gasket\u003c\/dd\u003e\n  \u003cdt\u003eInstallation\u003c\/dt\u003e\n  \u003cdd\u003eDirect fit when matched to the listed application\u003c\/dd\u003e\n  \u003cdt\u003eConnection\u003c\/dt\u003e\n  \u003cdd\u003eExhaust elbow to exhaust manifold\u003c\/dd\u003e\n  \u003cdt\u003eCompatible Manifold\u003c\/dt\u003e\n  \u003cdd\u003eAluminum exhaust manifold\u003c\/dd\u003e\n  \u003cdt\u003eDisplacement\u003c\/dt\u003e\n  \u003cdd\u003e3.7L\u003c\/dd\u003e\n  \u003cdt\u003eEngine Configuration\u003c\/dt\u003e\n  \u003cdd\u003e4-cylinder MerCruiser 170\/470 applications\u003c\/dd\u003e\n  \u003cdt\u003eYears\u003c\/dt\u003e\n  \u003cdd\u003e1985–1989\u003c\/dd\u003e\n\u003c\/dl\u003e\n\n\u003ch2\u003eWhat’s in the Box\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e1 x Exhaust elbow gasket\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eMounting hardware, exhaust elbows, manifolds, sealant, and complete mounting kits are not included.\u003c\/p\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n  \u003cli\u003eMake sure the engine is completely cool and disconnect the battery before beginning work.\u003c\/li\u003e\n  \u003cli\u003eConfirm that the engine is a listed MerCruiser 3.7L 4-cylinder 170\/470 application with the required aluminum exhaust manifold.\u003c\/li\u003e\n  \u003cli\u003eDrain or isolate the cooling system as required to access the exhaust elbow and manifold.\u003c\/li\u003e\n  \u003cli\u003eRemove the fasteners securing the exhaust elbow and carefully separate the elbow from the manifold.\u003c\/li\u003e\n  \u003cli\u003eRemove the old gasket and clean both mating surfaces thoroughly. Remove old gasket material, corrosion, and debris without damaging the surfaces.\u003c\/li\u003e\n  \u003cli\u003ePosition the new gasket correctly between the exhaust elbow and manifold.\u003c\/li\u003e\n  \u003cli\u003eReinstall the elbow and tighten the fasteners according to the engine manufacturer's specified sequence and torque values.\u003c\/li\u003e\n  \u003cli\u003eRestore the cooling system, reconnect the battery, start the engine, and inspect the joint for leaks.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\u003csummary\u003eWhich MerCruiser engines does this gasket fit?\u003c\/summary\u003e\u003cp\u003eIt is listed for MerCruiser 3.7L 4-cylinder 170 and 470 engines with aluminum exhaust manifolds from 1985–1989. Do not use the model name alone to confirm fitment; verify the year and manifold construction as well.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eDoes it fit every MerCruiser 470 engine?\u003c\/summary\u003e\u003cp\u003eNo. The listed application excludes 1976–1982 470 engines with cast-iron manifolds. Check the manifold on your engine before ordering.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eIs this a complete exhaust elbow mounting kit?\u003c\/summary\u003e\u003cp\u003eNo. This listing is for one exhaust elbow gasket only. Fasteners, an elbow, a manifold, and other mounting-kit components are not included.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat are the signs of a failed exhaust elbow gasket?\u003c\/summary\u003e\u003cp\u003ePossible signs include leakage at the elbow-to-manifold joint, rust or corrosion marks around the connection, overheating, or water entering areas where it should not. Stop operation and inspect the assembly if a leak is suspected.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eIs sealant required?\u003c\/summary\u003e\u003cp\u003eInstall the gasket according to the applicable service manual. Do not apply sealant unless the manufacturer specifically calls for it, because an unsuitable sealant can interfere with gasket positioning or sealing.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhen should the gasket be replaced?\u003c\/summary\u003e\u003cp\u003eReplace the gasket whenever the exhaust elbow or manifold is removed, or whenever inspection shows damage, compression loss, corrosion, or leakage.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eIs this an OEM part?\u003c\/summary\u003e\u003cp\u003eThis is an aftermarket replacement gasket. It is listed to replace MerCruiser reference numbers 27-18272 and 27-97863 and to cross-reference with the aftermarket numbers shown above.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat should I verify before ordering?\u003c\/summary\u003e\u003cp\u003eVerify the engine brand, 3.7L displacement, 4-cylinder 170\/470 model, 1985–1989 model-year range, and aluminum exhaust manifold. Also compare the original gasket and reference number.\u003c\/p\u003e\u003c\/details\u003e\n\n\u003ch2\u003eSafety \u0026amp; Important Info\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eAllow the engine and exhaust components to cool completely before service.\u003c\/li\u003e\n  \u003cli\u003eConfirm the aluminum-manifold requirement; cast-iron-manifold applications are not automatically interchangeable.\u003c\/li\u003e\n  \u003cli\u003eUse the engine service manual for fastener sequence, torque values, cooling-system procedures, and sealant requirements.\u003c\/li\u003e\n  \u003cli\u003eProfessional installation is recommended if you are unfamiliar with exhaust and cooling-system service.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMarine Replacement Parts\u003c\/strong\u003e — We supply replacement components for common marine engine and stern-drive service applications.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eApplication-Focused Listings\u003c\/strong\u003e — Product details identify the model, year, manifold, and reference-number conditions that affect fitment.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePractical Service Support\u003c\/strong\u003e — Compare your original component and consult the applicable service information before installation.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50723786686779,"sku":"23GT302","price":13.75,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/Exhaust_Elbow_Gasket_for_Mercury_MerCruiser_Stern_Drive_MCM_37L_1985-1989________27-18272_-_JLM_MARINE-8287557.jpg?v=1763031736"}],"url":"https:\/\/seasierra.com\/collections\/mercruiser-4-stroke-165-190hp-marine-engine-parts.oembed","provider":"SeaSierra","version":"1.0","type":"link"}