{"title":"MerCruiser 4-Stroke 188HP Marine Engine Parts","description":"\u003csection id=\"hero\" style=\"max-width:1100px;margin:0 auto;padding:16px 12px;\"\u003e\n \u003cp\u003eThis page supports MerCruiser 4‑Stroke 188 HP sterndrive engines and helps you quickly find compatible parts, routine service information, and troubleshooting tips. Inside you’ll find maintenance intervals, common replacement components, and quick diagnostic checks. You can also browse the main MerCruiser collection for a wider selection. Scroll to the bottom of the page to start browsing parts for this engine, and remember: on the collection page you can use the Filter \u0026amp; Sort controls to narrow results by horsepower, year range, and part category.\u003c\/p\u003e\n \u003cp\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser\" style=\"display:inline-block;padding:10px 14px;background:#004a7c;color:#fff;text-decoration:none;border-radius:6px;\"\u003eBrowse All MerCruiser Parts\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"identify-model\" style=\"max-width:1100px;margin:0 auto;padding:12px;\"\u003e\n \u003ch2\u003eHow to Identify Your 188HP Model\u003c\/h2\u003e\n \u003cul\u003e\n \u003cli\u003eLocate the serial plate: typically on the engine (intake manifold area, flame‑arrester bracket, or valve cover) and on the sterndrive’s transom assembly. Record both engine and drive serial numbers.\u003c\/li\u003e\n \u003cli\u003eModel naming: 188 HP often corresponds to the MerCruiser “888” package (Ford 302 V8, 2‑barrel carburetor). Confirm by checking carb type (2‑bbl), V8 layout, and distributor style.\u003c\/li\u003e\n \u003cli\u003eDrive family: many 188 HP packages used early MerCruiser sterndrives (MC‑1\/R). Note the outdrive’s serial to match water pump, bellows, and seal kit styles.\u003c\/li\u003e\n \u003cli\u003eConfiguration clues (4‑Stroke): V8 gasoline engine with separate engine oil and filter, raw‑water cooling pump in the drive or an added sea‑water pump, and a belt‑driven alternator.\u003c\/li\u003e\n \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"engine-overview\" style=\"max-width:1100px;margin:0 auto;padding:12px;\"\u003e\n \u003ch2\u003ePlatform Overview\u003c\/h2\u003e\n \u003ch3\u003eMerCruiser 888 (188 HP) V8 Package\u003c\/h3\u003e\n \u003ctable style=\"width:100%;border-collapse:collapse;\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;\"\u003eFeature\u003c\/th\u003e\n \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;\"\u003eDescription\u003c\/th\u003e\n \u003c\/tr\u003e\n \u003c\/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eConfiguration\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eFord 302 (5.0L) V8, 4‑stroke gasoline, 2‑barrel carbureted, distributor ignition; paired to early MerCruiser sterndrive (MC‑1 \/ R family).\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eCommon Models\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eMerCruiser 888 (188 HP) packages commonly seen in the early–mid 1970s.\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eAdvantages\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eStraightforward carburetion and ignition, strong low‑end torque, widely available service parts and hardware.\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eNotes\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eVerify outdrive serial to select correct water pump\/impeller kit, bellows, anodes, and seal kits. Many raw‑water systems rely on the drive‑mounted pump—timely impeller service is critical.\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003c\/tbody\u003e\n \u003c\/table\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"service-kits\" style=\"max-width:1100px;margin:0 auto;padding:12px;\"\u003e\n \u003ch2\u003eRoutine Maintenance \u0026amp; Service Parts\u003c\/h2\u003e\n \u003cp\u003eIntervals below are typical guidelines for 4‑stroke sterndrive use. Always consult your official service manual for your exact engine and drive.\u003c\/p\u003e\n \u003ctable style=\"width:100%;border-collapse:collapse;\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;\"\u003eItem\u003c\/th\u003e\n \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;\"\u003eInterval*\u003c\/th\u003e\n \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;\"\u003eRemarks\u003c\/th\u003e\n \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;\"\u003eParts Link\u003c\/th\u003e\n \u003c\/tr\u003e\n \u003c\/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eEngine oil \u0026amp; filter\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eUse marine‑rated oil and replace the filter at each oil change.\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\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:6px 4px;\"\u003eGear oil (lower unit)\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eEvery 100 hours or annually\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eChange before winter storage; inspect for metal or water intrusion.\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/lower-unit-seal-kits\"\u003eLower Unit Seal Kits\u003c\/a\u003e\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eSpark plugs\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eInspect every 100 hours; replace as needed\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eCheck gap and color; replace fouled or worn plugs.\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\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:6px 4px;\"\u003eFuel filter \/ water separator\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eEvery season or 100 hours\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eReplace element; drain water regularly if equipped.\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\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:6px 4px;\"\u003eWater pump impeller \/ kit\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eEvery 2–3 seasons (or 200 hours)\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eCritical for raw‑water cooling; replace sooner if stream is weak or after overheat.\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\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:6px 4px;\"\u003eAnodes (corrosion protection)\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eInspect every 50 hours; replace when 50% depleted\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eMatch anode alloy to your water (aluminum\/brackish, magnesium\/fresh, zinc\/salt).\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-anodes\"\u003eMerCruiser Anodes\u003c\/a\u003e\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003c\/tbody\u003e\n \u003c\/table\u003e\n \u003cp style=\"font-size:12px;color:#666;\"\u003e*Intervals are typical for leisure use; severe duty or long idle time may require more frequent service.\u003c\/p\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"common-parts\" style=\"max-width:1100px;margin:0 auto;padding:12px;\"\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 (impellers\/pumps): \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-impellers\"\u003eMerCruiser Impellers\u003c\/a\u003e or \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\/mercruiser-fuel-filters\"\u003eMerCruiser Fuel Filters\u003c\/a\u003e \u0026amp; \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\/starters\"\u003eStarters\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\n\u003c\/li\u003e\n \u003cli\u003ePropulsion Hardware: \u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser-propellers\"\u003eMerCruiser Propellers\u003c\/a\u003e\n\u003c\/li\u003e\n \u003c\/ul\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"troubleshooting\" style=\"max-width:1100px;margin:0 auto;padding:12px;\"\u003e\n \u003ch2\u003eCommon Symptoms \u0026amp; Quick Checks\u003c\/h2\u003e\n \u003ctable style=\"width:100%;border-collapse:collapse;\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;\"\u003eSymptom\u003c\/th\u003e\n \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;\"\u003eCheck First\u003c\/th\u003e\n \u003cth style=\"text-align:left;border-bottom:1px solid #ccc;\"\u003eRelated Parts\u003c\/th\u003e\n \u003c\/tr\u003e\n \u003c\/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eWeak tell‑tale stream or overheat alarm\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eInspect intake screens for debris; verify impeller age; check hoses and thermostat\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eWater pump impeller kit, thermostat, intake screens\/hoses\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eHard starting \/ rough idle\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eConfirm clean fuel and fresh spark plugs; check choke operation and base timing\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eFuel filter element, spark plugs, ignition cap\/rotor\/wires, carb tuning parts\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003ePoor acceleration \/ power loss\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eCheck fuel delivery and anti‑ventilation plate\/prop condition; verify throttle linkage\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eFuel pump\/filter, propeller, ignition service parts, carb components\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eGearcase noise or milky gear oil\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eLook for water intrusion; inspect prop‑shaft seals and drain\/fill plug gaskets\u003c\/td\u003e\n \u003ctd style=\"padding:6px 4px;\"\u003eSeal kit, drain\/fill gaskets, gear lube\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003c\/tbody\u003e\n \u003c\/table\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"faq\" style=\"max-width:1100px;margin:0 auto;padding:12px;\"\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\u003eSome are, but not all. MerCruiser packages changed over time (carburetion, ignition, and sterndrive families). Always match by engine serial number, drive serial number, and component family (e.g., MC‑1 vs R\/MR vs Alpha).\u003c\/p\u003e\n \u003c\/details\u003e\n \u003cdetails\u003e\n \u003csummary\u003eWhen should the raw‑water impeller be replaced?\u003c\/summary\u003e\n \u003cp\u003eTypical replacement is every 2–3 seasons or about 200 hours. Replace sooner after any overheat or if the water stream weakens.\u003c\/p\u003e\n \u003c\/details\u003e\n \u003cdetails\u003e\n \u003csummary\u003eHow often should I change lower unit gear oil?\u003c\/summary\u003e\n \u003cp\u003eAt least annually or every 100 hours. Change before winter storage and inspect for signs of water or metal.\u003c\/p\u003e\n \u003c\/details\u003e\n \u003cdetails\u003e\n \u003csummary\u003eWhat information helps confirm part compatibility?\u003c\/summary\u003e\n \u003cp\u003eEngine serial number, sterndrive serial number, carb type (2‑bbl vs 4‑bbl), ignition style (points vs electronic), and any cooling or charging upgrades. Photos of the nameplate and the part you’re replacing are very helpful.\u003c\/p\u003e\n \u003c\/details\u003e\n\u003c\/section\u003e\n\n\u003csection id=\"cta\" style=\"max-width:1100px;margin:0 auto;padding:16px 12px;\"\u003e\n \u003cp\u003eReady to find parts by horsepower, year, and model? Start in the main MerCruiser collection and use the Filter \u0026amp; Sort tools to narrow the results for your 188 HP package.\u003c\/p\u003e\n \u003cp\u003e\u003ca href=\"https:\/\/seasierra.com\/collections\/mercruiser\" style=\"display:inline-block;padding:10px 14px;background:#004a7c;color:#fff;text-decoration:none;border-radius:6px;\"\u003eBrowse All MerCruiser Parts\u003c\/a\u003e\u003c\/p\u003e\n \u003cp style=\"font-size:12px;color:#666;\"\u003eIf you’re unsure about your model, send us a photo of the nameplate and the part you need and we’ll help verify compatibility.\u003c\/p\u003e\n\u003c\/section\u003e","products":[{"product_id":"bushing-drive-shaft-housing-fits-mercury-mercruiser-replaces-23-32632","title":"Bushing, Drive Shaft Housing – Fits Mercury\/Mercruiser (Replaces 23-32632)","description":"\u003cstyle\u003e\n .ss-table-wrap { overflow-x:auto; -webkit-overflow-scrolling:touch; }\n table.ss-table { width:100%; border-collapse:collapse; min-width:640px; }\n table.ss-table th, table.ss-table td { padding:10px 12px; border:1px solid #e5e7eb; text-align:left; vertical-align:top; }\n table.ss-table th { white-space:nowrap; word-break:normal; letter-spacing:normal; font-weight:600; background:#f8fafc; }\n @media (max-width:480px){\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\u003eDrive Shaft Housing Bushing\u003c\/strong\u003e is designed for a wide range of Mercury\/Mercruiser stern drive applications from 1963 to 1990. It fits popular models including Alpha One, 120\/140, 165, 228, 233, 260, 470, 485, 888, and 898.\u003c\/p\u003e\n \u003cp\u003eThis part is a direct replacement for Mercury and Mercruiser part number 23-32632.\u003c\/p\u003e\n \u003cul\u003e\n \u003cli\u003eInstalls via a secure press-fit method.\u003c\/li\u003e\n \u003c\/ul\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n \u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n \u003cp\u003eUse this matrix to confirm equivalent references across OEM and aftermarket.\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\u003eMercury\u003c\/td\u003e\n \u003ctd\u003e23-32632\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e23-32632\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003c\/tbody\u003e\n \u003c\/table\u003e\n \u003c\/div\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n \u003ch2\u003eEngine \u0026amp; Model Compatibility\u003c\/h2\u003e\n \u003cp\u003eConfirm your engine model and year in the table below.\u003c\/p\u003e\n \u003cp\u003eThis component is an exact-fit for a wide range of Mercruiser sterndrive models manufactured between 1963 and 1990.\u003c\/p\u003e\n \u003cdiv class=\"ss-table-wrap\"\u003e\n \u003ctable class=\"ss-table\" aria-label=\"Engine \u0026amp; Model Compatibility\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eBrand\u003c\/th\u003e\n \u003cth\u003eModel\u003c\/th\u003e\n \u003cth\u003eRated HP\u003c\/th\u003e\n \u003cth\u003eStroke\u003c\/th\u003e\n \u003cth\u003eYears\u003c\/th\u003e\n \u003cth\u003eOEM Part No.\u003c\/th\u003e\n \u003cth\u003eNotes\u003c\/th\u003e\n \u003c\/tr\u003e\n \u003c\/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e120\/140\u003c\/td\u003e\n\u003ctd\u003e120–140\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1967–1969\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 2062141-2791956\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e120\/140\u003c\/td\u003e\n\u003ctd\u003e120–140\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1970–1977\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 2791957-4893634\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e120\/140\u003c\/td\u003e\n\u003ctd\u003e120–140\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1978–1982\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 4893635-6225576\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e160\u003c\/td\u003e\n\u003ctd\u003e160\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1967–1969\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 2065190-2763441\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e165\u003c\/td\u003e\n\u003ctd\u003e165\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1970–1977\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 2763442-4890459\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e165\u003c\/td\u003e\n\u003ctd\u003e165\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1978–1981\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 4890460 \u0026amp; Up\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e225-S\u003c\/td\u003e\n\u003ctd\u003e225\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1974\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 3856268-4200499\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e228\u003c\/td\u003e\n\u003ctd\u003e228\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1978–1982\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 4898730-6225576\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e233\u003c\/td\u003e\n\u003ctd\u003e233\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1975–1977\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 4200500 \u0026amp; Up\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e250\u003c\/td\u003e\n\u003ctd\u003e250\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1977\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 4791300-4898729\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e260\u003c\/td\u003e\n\u003ctd\u003e260\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1978–1982\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 4898730-6225576\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e470\u003c\/td\u003e\n\u003ctd\u003e170\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1976–1977\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 4208730-4893934\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e470\u003c\/td\u003e\n\u003ctd\u003e170\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1978–1982\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 4893835-6225576\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e485\u003c\/td\u003e\n\u003ctd\u003e185\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1980–1982\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 4893835 \u0026amp; Up\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e888\u003c\/td\u003e\n\u003ctd\u003e188\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1971–1977\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 3106717 AND UP\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e898\u003c\/td\u003e\n\u003ctd\u003e228\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1978–1982\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 4898730-6225576\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003e898\/228\u003c\/td\u003e\n\u003ctd\u003e228\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1977\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 4782330-4898729\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003eI\u003c\/td\u003e\n\u003ctd\u003e-\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1963\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 1534570-1684187\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003eIA\/IB\/IC (EZ-SHIFT)\u003c\/td\u003e\n\u003ctd\u003e-\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1965–1966\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 1776349-2065189\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003eIA\/IB\/IC\u003c\/td\u003e\n\u003ctd\u003e-\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1964\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 1684188-1777798\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003eR\/MR\/ALPHA ONE (Sterndrive)\u003c\/td\u003e\n\u003ctd\u003e-\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1983–1990\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 6225577-0F386995\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003ctr\u003e\n\u003ctd\u003eMercruiser\u003c\/td\u003e\n\u003ctd\u003eR\/MR\/ALPHA ONE (Transom Assembly)\u003c\/td\u003e\n\u003ctd\u003e-\u003c\/td\u003e\n\u003ctd\u003e4-Stroke\u003c\/td\u003e\n\u003ctd\u003e1983–1990\u003c\/td\u003e\n\u003ctd\u003e23-32632\u003c\/td\u003e\n\u003ctd\u003eS\/N: 6216687-0F386995\u003c\/td\u003e\n\u003c\/tr\u003e\n \u003c\/tbody\u003e\n \u003c\/table\u003e\n \u003c\/div\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n \u003ch2\u003eTechnical Specs\u003c\/h2\u003e\n \u003cdl\u003e\n \u003cdt\u003eProduct Type\u003c\/dt\u003e\n\u003cdd\u003eDrive Shaft Housing Bushing\u003c\/dd\u003e\n \u003cdt\u003eInstallation\u003c\/dt\u003e\n\u003cdd\u003ePress-fit\u003c\/dd\u003e\n \u003cdt\u003eDimensions\u003c\/dt\u003e\n\u003cdd\u003e0.75\" L x 4.0\" W x 5.13\" H (19.05 x 101.6 x 130.3 mm)\u003c\/dd\u003e\n \u003cdt\u003eWeight\u003c\/dt\u003e\n\u003cdd\u003e1 pound (0.45 kg)\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 Bushing (Replaces 23-32632)\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\u003eDisconnect the battery and ensure the engine is off and completely cool before starting work.\u003c\/li\u003e\n \u003cli\u003eDrain the gear lube from the sterndrive unit completely.\u003c\/li\u003e\n \u003cli\u003eCarefully separate the upper and lower units of the sterndrive.\u003c\/li\u003e\n \u003cli\u003eLocate the old drive shaft housing bushing within the upper housing assembly.\u003c\/li\u003e\n \u003cli\u003eUsing a suitable press or bushing driver, carefully remove the old bushing. Take care not to score or damage the housing bore.\u003c\/li\u003e\n \u003cli\u003eThoroughly clean the housing bore to remove any old sealant, corrosion, or debris.\u003c\/li\u003e\n \u003cli\u003eAlign the new bushing and use a press to drive it in evenly until it is fully and correctly seated.\u003c\/li\u003e\n \u003cli\u003eReassemble the upper and lower sterndrive units, applying new gaskets and seals as required by your service manual.\u003c\/li\u003e\n \u003cli\u003eRefill the sterndrive with fresh, manufacturer-recommended gear lube.\u003c\/li\u003e\n \u003cli\u003eReconnect the battery, start the engine, and check for any leaks or unusual noises before full operation.\u003c\/li\u003e\n \u003c\/ol\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n \u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n \u003cdetails\u003e\n \u003csummary\u003eHow do I know if my drive shaft housing bushing is failing?\u003c\/summary\u003e\n \u003cp\u003eCommon signs include excessive vibration from the sterndrive, unusual grinding or roaring noises, or visible play in the driveshaft when moved by hand. A visual inspection during service may reveal obvious wear, cracking, or deformation of the bushing.\u003c\/p\u003e\n \u003c\/details\u003e\n \u003cdetails\u003e\n \u003csummary\u003eWhat happens if I don't replace a worn bushing?\u003c\/summary\u003e\n \u003cp\u003eA failed bushing can lead to driveshaft misalignment, causing accelerated wear on connected seals and gears. This can result in water intrusion into the gearcase and eventual catastrophic failure of the sterndrive if left unaddressed.\u003c\/p\u003e\n \u003c\/details\u003e\n \u003cdetails\u003e\n \u003csummary\u003eIs a special tool required for installation?\u003c\/summary\u003e\n \u003cp\u003eYes, installation requires a workshop press or a specific bushing driver\/arbor set. This allows you to press the old bushing out and the new one in without damaging the new bushing or the aluminum housing. It is not recommended to use a hammer.\u003c\/p\u003e\n \u003c\/details\u003e\n \u003cdetails\u003e\n \u003csummary\u003eCan I replace this bushing without removing the sterndrive from the boat?\u003c\/summary\u003e\n \u003cp\u003eNo. You must remove the entire sterndrive assembly from the transom shield to separate the upper and lower units. This is the only way to access the drive shaft housing and replace the bushing.\u003c\/p\u003e\n \u003c\/details\u003e\n \u003cdetails\u003e\n \u003csummary\u003eHow does this aftermarket part compare to the OEM original?\u003c\/summary\u003e\n \u003cp\u003eThis part is manufactured to meet or exceed original equipment (OEM) specifications for material hardness, dimensions, and fit. It provides a reliable, cost-effective alternative to the original manufacturer's part.\u003c\/p\u003e\n \u003c\/details\u003e\n \u003cdetails\u003e\n \u003csummary\u003eWhat are the OEM vs. Aftermarket standards for this part?\u003c\/summary\u003e\n \u003cp\u003eThis listing is for an aftermarket replacement part, not an OEM component. It is built to OEM-level specifications with comparable materials and performance characteristics. Our parts are manufactured in an ISO 9002 certified facility and are batch-inspected for quality and consistency.\u003c\/p\u003e\n \u003c\/details\u003e\n \u003cdetails\u003e\n \u003csummary\u003eWhat are your shipping speed and costs?\u003c\/summary\u003e\n \u003cp\u003eWe ship worldwide quickly, with typical transit times of 5–15 days for most regions. Standard shipping is free for all orders. Expedited shipping options and costs, where available, will be displayed at checkout.\u003c\/p\u003e\n \u003c\/details\u003e\n \u003cdetails\u003e\n \u003csummary\u003eWhat is the warranty and return policy?\u003c\/summary\u003e\n \u003cp\u003eThis product is covered by a 1-year warranty against manufacturing defects under normal marine use. If you encounter any issues, please contact our support team with your order details. Returns are accepted within our standard window, provided the part is unused and in its original packaging. Please see our full policy page or reach out for instructions.\u003c\/p\u003e\n \u003c\/details\u003e\n\u003c\/section\u003e\n\u003csection\u003e\n \u003ch2\u003eSafety \u0026amp; Important Info\u003c\/h2\u003e\n \u003cul\u003e\n \u003cli\u003eVerify images and specifications against your original part before ordering. If anything differs—even if your model appears on a compatibility list—do not purchase.\u003c\/li\u003e\n \u003cli\u003eThis is an aftermarket replacement component, not an Original Equipment Manufacturer (OEM) part.\u003c\/li\u003e\n \u003cli\u003eProfessional installation is strongly recommended for safety, proper function, and to prevent damage to the sterndrive.\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\u003ePro-Grade Standards\u003c\/strong\u003e — We supply marine parts engineered to OEM-level tolerances and rigorously tested for real-world saltwater and freshwater conditions.\u003c\/li\u003e\n \u003cli\u003e\n\u003cstrong\u003eFast Global Fulfillment\u003c\/strong\u003e — With partners worldwide, we offer free standard delivery to most regions in 5–15 business days.\u003c\/li\u003e\n \u003cli\u003e\n\u003cstrong\u003eManufacturer-Direct Value\u003c\/strong\u003e — By working directly with manufacturers, we provide fair, transparent pricing without compromising on materials or quality control.\u003c\/li\u003e\n \u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50587183513915,"sku":"23-32632","price":15.99,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/23-32632_0507bef5-afd3-437d-a114-2c5ac373d52f.jpg?v=1757934139"},{"product_id":"thermostat-housing-gasket-fits-mercury-mercruiser-ford-v8-engines-replaces-27-54506","title":"Thermostat Housing Gasket – Fits Mercury Mercruiser Ford V8 Engines (Replaces 27-54506)","description":"\u003csection\u003e\n\u003c!-- 🔧 Table Styles (include only once per page) --\u003e\n\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; \/* Do not wrap *\/\n word-break:normal; \/* Don’t break words *\/\n letter-spacing:normal; \/* Prevent theme styles from stretching letters *\/\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\n\u003ch2\u003eProduct Details\u003c\/h2\u003e\n\u003cp\u003eThis \u003cstrong\u003eThermostat Housing Gasket – Fits Mercury Mercruiser Ford V8 Engines (Replaces 27-54506)\u003c\/strong\u003e is designed for a precise fit on Mercury Mercruiser Ford V8 302\/351 engines from 1970–1977. It creates a reliable seal specifically for raw water cooled applications, preventing coolant leaks and ensuring proper engine operating temperature.\u003c\/p\u003e\n\u003cp\u003eThis gasket serves as a direct replacement for Mercury Marine 27-54506, Sierra 18-0349, and PCM RM0001, offering a reliable interchange for multiple part numbers.\u003c\/p\u003e\n\u003cul\u003e\n \u003cli\u003eInstalls between the lower thermostat housing and the engine intake manifold.\u003c\/li\u003e\n \u003cli\u003eEngineered specifically for raw water (seawater) cooling systems.\u003c\/li\u003e\n \u003cli\u003eIncludes one gasket for a complete replacement.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n\u003cp\u003eUse this matrix to confirm equivalent references across OEM and aftermarket.\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\u003eMercury Marine\u003c\/td\u003e\n \u003ctd\u003e27-54506\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eSierra\u003c\/td\u003e\n \u003ctd\u003e18-0349\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003ePCM\u003c\/td\u003e\n \u003ctd\u003eRM0001\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 your engine model\/year in the table below.\u003c\/p\u003e\n\u003cp\u003eFor Mercruiser models, verify your engine's serial number falls within the specified range for a guaranteed match.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n \u003ctable class=\"ss-table\" aria-label=\"Engine \u0026amp; Model Compatibility\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eBrand\u003c\/th\u003e\n \u003cth\u003eModel\u003c\/th\u003e\n \u003cth\u003eRated HP\u003c\/th\u003e\n \u003cth\u003eStroke\u003c\/th\u003e\n \u003cth\u003eYears\u003c\/th\u003e\n \u003cth\u003eOEM Part No.\u003c\/th\u003e\n \u003cth\u003eNotes\u003c\/th\u003e\n \u003c\/tr\u003e\n \u003c\/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e215 (4 BBL.) FORD 302 V-8\u003c\/td\u003e\n \u003ctd\u003e215\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1970–1972\u003c\/td\u003e\n \u003ctd\u003e27-54506\u003c\/td\u003e\n \u003ctd\u003eSerial #2781153 through #3395720\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e215 MIE FORD 302 V-8\u003c\/td\u003e\n \u003ctd\u003e215\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1970–1972\u003c\/td\u003e\n \u003ctd\u003e27-54506\u003c\/td\u003e\n \u003ctd\u003eSerial #2781153 through #3563181\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e225 (4 BBL.) FORD 302 V-8\u003c\/td\u003e\n \u003ctd\u003e225\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1973–1974\u003c\/td\u003e\n \u003ctd\u003e27-54506\u003c\/td\u003e\n \u003ctd\u003eSerial #3385721 through #4166999\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e225 MIE FORD 302 V-8\u003c\/td\u003e\n \u003ctd\u003e225\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1973–1974\u003c\/td\u003e\n \u003ctd\u003e27-54506\u003c\/td\u003e\n \u003ctd\u003eSerial #3385721 through #4176999\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e225-S (4 BBL.) FORD 302 V-8\u003c\/td\u003e\n \u003ctd\u003e225\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1973–1974\u003c\/td\u003e\n \u003ctd\u003e27-54506\u003c\/td\u003e\n \u003ctd\u003eSerial #3385721 through #4166999\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e233 FORD 351 V-8\u003c\/td\u003e\n \u003ctd\u003e233\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1975–1977\u003c\/td\u003e\n \u003ctd\u003e27-54506\u003c\/td\u003e\n \u003ctd\u003eSerial #4173000 through #4902304\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e233 MIE FORD 351 V-8\u003c\/td\u003e\n \u003ctd\u003e233\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1975–1976\u003c\/td\u003e\n \u003ctd\u003e27-54506\u003c\/td\u003e\n \u003ctd\u003eSerial #4173000 through #4775784\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e255 FORD 351 V-8\u003c\/td\u003e\n \u003ctd\u003e255\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1973–1974\u003c\/td\u003e\n \u003ctd\u003e27-54506\u003c\/td\u003e\n \u003ctd\u003eSerial #3258728 through #4175499\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e255 MIE FORD 351 V-8\u003c\/td\u003e\n \u003ctd\u003e255\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1973–1974\u003c\/td\u003e\n \u003ctd\u003e27-54506\u003c\/td\u003e\n \u003ctd\u003eSerial #3258728 through #4178299\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e888 (2 BBL.) FORD 302 V-8\u003c\/td\u003e\n \u003ctd\u003e188\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1971–1977\u003c\/td\u003e\n \u003ctd\u003e27-54506\u003c\/td\u003e\n \u003ctd\u003eSerial #3108723 and up\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\u003eThermostat Housing Gasket\u003c\/dd\u003e\n \u003cdt\u003eInstallation\u003c\/dt\u003e\n\u003cdd\u003eFits between lower thermostat housing and engine intake manifold\u003c\/dd\u003e\n \u003cdt\u003eFuel Type\u003c\/dt\u003e\n\u003cdd\u003eGasoline\u003c\/dd\u003e\n \u003cdt\u003eHousing Material\u003c\/dt\u003e\n\u003cdd\u003eGasket Material\u003c\/dd\u003e\n \u003cdt\u003eDimensions\u003c\/dt\u003e\n\u003cdd\u003e11.5 × 11.0 × 0.1 inches\u003c\/dd\u003e\n \u003cdt\u003eWeight\u003c\/dt\u003e\n\u003cdd\u003e0.01 lbs (4.5 g)\u003c\/dd\u003e\n \u003cdt\u003eOther Technical Attributes\u003c\/dt\u003e\n\u003cdd\u003eFor raw water cooled applications only\u003c\/dd\u003e\n\u003c\/dl\u003e\n\n\u003ch2\u003eWhat’s in the Box\u003c\/h2\u003e\n\u003cul\u003e\n \u003cli\u003e\n\u003cspan style=\"color:#d0021b;\"\u003e1 ×\u003c\/span\u003e Thermostat Housing Gasket (27-54506)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n \u003cli\u003eDisconnect the vessel's battery and ensure the engine is completely cool.\u003c\/li\u003e\n \u003cli\u003eDrain the engine block's cooling system to a level below the thermostat housing.\u003c\/li\u003e\n \u003cli\u003eCarefully remove the bolts securing the thermostat housing, and detach any connected hoses.\u003c\/li\u003e\n \u003cli\u003eRemove the old housing and gasket. Thoroughly clean both mating surfaces on the housing and the intake manifold, ensuring they are free of old gasket material, sealant, and corrosion.\u003c\/li\u003e\n \u003cli\u003ePosition the new gasket onto the manifold, aligning it with the bolt holes.\u003c\/li\u003e\n \u003cli\u003ePlace the thermostat housing over the gasket, re-insert the bolts, and tighten them to the manufacturer's specified torque in a star or crisscross pattern.\u003c\/li\u003e\n \u003cli\u003eReconnect hoses, refill the cooling system with the appropriate coolant, and check for leaks.\u003c\/li\u003e\n \u003cli\u003eReconnect the battery, then run the engine and monitor for any leaks or overheating issues.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\n \u003csummary\u003eHow do I know if my thermostat housing gasket is failing?\u003c\/summary\u003e\n \u003cp\u003eSigns of a failing gasket include visible coolant leaks around the thermostat housing, engine overheating, or a low coolant level warning. You may also notice white steam or a sweet smell from the engine compartment.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n \u003csummary\u003eCan I reuse my old gasket after removing the housing?\u003c\/summary\u003e\n \u003cp\u003eNo. Gaskets are designed for one-time use. They compress and deform to create a seal, and once removed, they will not seal properly again, leading to leaks. Always replace the gasket whenever the thermostat housing is removed.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n \u003csummary\u003eIs any sealant required for this gasket?\u003c\/summary\u003e\n \u003cp\u003eMost modern gaskets of this type are designed to be installed dry. However, always consult your engine's service manual. If sealant is recommended, use only the specified type and apply it sparingly to avoid blocking coolant passages.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n \u003csummary\u003eWhat does \"for raw water cooled applications only\" mean?\u003c\/summary\u003e\n \u003cp\u003eThis means the gasket material is formulated to withstand direct exposure to seawater or lake water used for engine cooling. It is not intended for \"closed cooling\" systems that use a treated antifreeze mixture.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n \u003csummary\u003eWhat is the difference between this aftermarket gasket and an OEM one?\u003c\/summary\u003e\n \u003cp\u003eThis aftermarket gasket is engineered to meet or exceed OEM specifications for fit, form, and function. While the exact material composition may differ slightly, it is designed to provide a comparable seal and service life under the same operating conditions.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n \u003csummary\u003eHow often should this gasket be replaced?\u003c\/summary\u003e\n \u003cp\u003eThe gasket should be replaced any time the thermostat is serviced or the housing is removed. There is no fixed replacement interval, but it's good practice to inspect it for leaks during routine engine maintenance.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n \u003csummary\u003eOEM vs. Aftermarket?\u003c\/summary\u003e\n \u003cp\u003eThis listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n \u003csummary\u003eShipping speed \u0026amp; cost\u003c\/summary\u003e\n \u003cp\u003eWe ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n \u003csummary\u003eWarranty \u0026amp; returns\u003c\/summary\u003e\n \u003cp\u003eCovered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused in original condition). See our policy page or reach out for instructions.\u003c\/p\u003e\n\u003c\/details\u003e\n\n\u003ch2\u003eSafety \u0026amp; Important Info\u003c\/h2\u003e\n\u003cul\u003e\n \u003cli\u003eVerify images\/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.\u003c\/li\u003e\n \u003cli\u003eThis is an aftermarket replacement, not an OEM component.\u003c\/li\u003e\n \u003cli\u003eProfessional installation is recommended for safety and performance.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n\u003cul\u003e\n \u003cli\u003e\n\u003cstrong\u003ePro-Grade Standards\u003c\/strong\u003e — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.\u003c\/li\u003e\n \u003cli\u003e\n\u003cstrong\u003eFast Global Fulfillment\u003c\/strong\u003e — Free standard delivery to most regions in 5–15 days.\u003c\/li\u003e\n \u003cli\u003e\n\u003cstrong\u003eManufacturer-Direct Value\u003c\/strong\u003e — Fair pricing without compromising on materials or QC.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50590214979899,"sku":"27-54506","price":7.49,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/27-54506_76bda95d-3202-4fe0-bd0a-c7ecaa7538b0.jpg?v=1758080314"},{"product_id":"timing-cover-gasket-fits-mercury-marine-mercruiser-ford-v8-engines-replaces-27-56108","title":"Timing Cover Gasket – Fits Mercury Marine\/Mercruiser Ford V8 Engines (Replaces 27-56108)","description":"\u003csection\u003e\n\u003c!-- 🔧 Table Styles (include only once per page) --\u003e\n\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; \/* Do not wrap *\/\n word-break:normal; \/* Don’t break words *\/\n letter-spacing:normal; \/* Prevent theme styles from stretching letters *\/\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\u003ch2\u003eProduct Details\u003c\/h2\u003e\n\u003cp\u003eThis replacement \u003cstrong\u003eTiming Cover Gasket – Fits Mercury Marine\/Mercruiser Ford V8 Engines (Replaces 27-56108)\u003c\/strong\u003e is designed for Mercruiser inboard engines with Ford V8 302 and 351 cubic inch powerplants manufactured from 1970–1977. It ensures a precise seal for the engine's timing chain cover assembly.\u003c\/p\u003e\n\u003cp\u003eThis gasket provides a direct interchange for Mercury part numbers 27-56108 and 56108, and Quicksilver 27-56108. It is manufactured from high-quality paper\/fiber gasket material to meet OEM factory specifications.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eInstalls on the engine timing chain cover.\u003c\/li\u003e\n\u003cli\u003eDesigned for gasoline-fueled marine engines.\u003c\/li\u003e\n\u003cli\u003eEngineered to prevent oil and coolant leaks from the front of the engine.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n\u003cp\u003eUse this matrix to confirm equivalent references across OEM and aftermarket.\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\u003eMercury\u003c\/td\u003e\n \u003ctd\u003e27-56108\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercury\u003c\/td\u003e\n \u003ctd\u003e56108\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eQuicksilver\u003c\/td\u003e\n \u003ctd\u003e27-56108\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\u003eConfirm your engine model\/year in the table below.\u003c\/p\u003e\n\u003cp\u003eThis gasket is compatible with specific Mercruiser sterndrive and inboard (MIE) models equipped with Ford V8 engines. Please check your engine's serial number to ensure an exact match.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n \u003ctable class=\"ss-table\" aria-label=\"Engine \u0026amp; Model Compatibility\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eBrand\u003c\/th\u003e\n \u003cth\u003eModel\u003c\/th\u003e\n \u003cth\u003eRated HP\u003c\/th\u003e\n \u003cth\u003eStroke\u003c\/th\u003e\n \u003cth\u003eYears\u003c\/th\u003e\n \u003cth\u003eOEM Part No.\u003c\/th\u003e\n \u003cth\u003eNotes\u003c\/th\u003e\n \u003c\/tr\u003e\n \u003c\/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e215 (4 BBL.) FORD 302 V-8\u003c\/td\u003e\n \u003ctd\u003e215\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1970–1972\u003c\/td\u003e\n \u003ctd\u003e27-56108\u003c\/td\u003e\n \u003ctd\u003eSerial range: 2781153-3395720\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e215 MIE FORD 302 V-8\u003c\/td\u003e\n \u003ctd\u003e215\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1970–1972\u003c\/td\u003e\n \u003ctd\u003e27-56108\u003c\/td\u003e\n \u003ctd\u003eSerial range: 2781153-3563181\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e225 (4 BBL.) FORD 302 V-8\u003c\/td\u003e\n \u003ctd\u003e225\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1973–1974\u003c\/td\u003e\n \u003ctd\u003e27-56108\u003c\/td\u003e\n \u003ctd\u003eSerial range: 3385721-4166999\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e225 MIE FORD 302 V-8\u003c\/td\u003e\n \u003ctd\u003e225\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1973–1974\u003c\/td\u003e\n \u003ctd\u003e27-56108\u003c\/td\u003e\n \u003ctd\u003eSerial range: 3385721-4176999\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e225-S (4 BBL.) FORD 302 V-8\u003c\/td\u003e\n \u003ctd\u003e225\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1973–1974\u003c\/td\u003e\n \u003ctd\u003e27-56108\u003c\/td\u003e\n \u003ctd\u003eSerial range: 3385721-4166999\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e233 FORD 351 V-8\u003c\/td\u003e\n \u003ctd\u003e233\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1975–1977\u003c\/td\u003e\n \u003ctd\u003e27-56108\u003c\/td\u003e\n \u003ctd\u003eSerial range: 4173000-4902304\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e233 MIE FORD 351 V-8\u003c\/td\u003e\n \u003ctd\u003e233\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1975–1976\u003c\/td\u003e\n \u003ctd\u003e27-56108\u003c\/td\u003e\n \u003ctd\u003eSerial range: 4173000-4775784\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e255 FORD 351 V-8\u003c\/td\u003e\n \u003ctd\u003e255\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1973–1974\u003c\/td\u003e\n \u003ctd\u003e27-56108\u003c\/td\u003e\n \u003ctd\u003eSerial range: 3258728-4175499\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e255 MIE FORD 351 V-8\u003c\/td\u003e\n \u003ctd\u003e255\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1973–1974\u003c\/td\u003e\n \u003ctd\u003e27-56108\u003c\/td\u003e\n \u003ctd\u003eSerial range: 3258728-4178299\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e888 (2 BBL.) FORD 302 V-8\u003c\/td\u003e\n \u003ctd\u003e188\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1971–1977\u003c\/td\u003e\n \u003ctd\u003e27-56108\u003c\/td\u003e\n \u003ctd\u003eSerial range: 3108723 and up\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\u003eTiming Cover Gasket\u003c\/dd\u003e\n \u003cdt\u003eInstallation\u003c\/dt\u003e\n\u003cdd\u003eEngine Timing Chain Cover\u003c\/dd\u003e\n \u003cdt\u003eFuel Type\u003c\/dt\u003e\n\u003cdd\u003eGasoline\u003c\/dd\u003e\n \u003cdt\u003eHousing Material\u003c\/dt\u003e\n\u003cdd\u003ePaper\/Fiber Gasket Material\u003c\/dd\u003e\n \u003cdt\u003eDimensions\u003c\/dt\u003e\n\u003cdd\u003e25.5\" L x 29.5\" W x 0.1\" H\u003c\/dd\u003e\n \u003cdt\u003eWarranty\u003c\/dt\u003e\n\u003cdd\u003e30 days (Green Bay Propeller \u0026amp; Marine LLC)\u003c\/dd\u003e\n \u003cdt\u003eOther Technical Attributes\u003c\/dt\u003e\n\u003cdd\u003eOEM Factory Part\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 Timing Cover Gasket (27-56108)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n \u003cli\u003eDrain the engine coolant completely to avoid spills.\u003c\/li\u003e\n \u003cli\u003eRemove the serpentine belt and any accessories blocking the timing cover, such as the water pump and power steering pump.\u003c\/li\u003e\n \u003cli\u003eRemove the crankshaft pulley\/harmonic balancer using an appropriate puller tool.\u003c\/li\u003e\n \u003cli\u003eCarefully unbolt and remove the timing cover from the engine block.\u003c\/li\u003e\n \u003cli\u003eRemove the old gasket and thoroughly clean both the engine block and timing cover mating surfaces. Ensure they are free of old gasket material, oil, and debris.\u003c\/li\u003e\n \u003cli\u003ePosition the new gasket onto the engine block, aligning it with the bolt holes.\u003c\/li\u003e\n \u003cli\u003eReinstall the timing cover, ensuring it is seated correctly over the gasket.\u003c\/li\u003e\n \u003cli\u003eTighten the cover bolts to the manufacturer's specified torque sequence and values.\u003c\/li\u003e\n \u003cli\u003eReinstall the crankshaft pulley, accessories, and serpentine belt.\u003c\/li\u003e\n \u003cli\u003eRefill the engine with coolant and check for leaks after starting the engine.\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 my timing cover gasket is failing?\u003c\/summary\u003e\n \u003cp\u003eCommon signs of a faulty timing cover gasket include visible oil or coolant leaks from the front of the engine, near the crankshaft pulley. You may also notice a low coolant level or milky, contaminated engine oil, which indicates coolant is mixing with the oil.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n \u003csummary\u003eWill this gasket fit my specific Ford V8 engine?\u003c\/summary\u003e\n \u003cp\u003eThis gasket is specifically designed for the Mercruiser models listed in the compatibility table, which use Ford 302 and 351 V8 engines from 1970–1977. Always verify your engine's model and serial number against the compatibility chart before ordering.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n \u003csummary\u003eShould I use sealant with this paper gasket?\u003c\/summary\u003e\n \u003cp\u003eWhile this gasket is designed to seal on its own, some mechanics apply a thin layer of gasket sealant (such as Permatex Aviation Form-A-Gasket) to one or both sides to improve the seal and hold the gasket in place during installation. Consult your engine's service manual for the recommended procedure.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n \u003csummary\u003eWhat are the signs of an improper installation?\u003c\/summary\u003e\n \u003cp\u003eIf the gasket is not installed correctly, you will likely see immediate or premature leaks of oil or coolant from the timing cover area. Over-tightening the bolts can damage the gasket or cover, while under-tightening can lead to an insufficient seal.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n \u003csummary\u003eOEM vs. Aftermarket?\u003c\/summary\u003e\n \u003cp\u003eThis listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n \u003csummary\u003eShipping speed \u0026amp; cost\u003c\/summary\u003e\n \u003cp\u003eWe ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n \u003csummary\u003eWarranty \u0026amp; returns\u003c\/summary\u003e\n \u003cp\u003eCovered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused \u0026amp; in original condition). See our policy page or reach out for instructions.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003ch2\u003eSafety \u0026amp; Important Info\u003c\/h2\u003e\n\u003cul\u003e\n \u003cli\u003eVerify images\/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.\u003c\/li\u003e\n \u003cli\u003eThis is an aftermarket replacement, not an OEM component.\u003c\/li\u003e\n \u003cli\u003eProfessional installation is recommended for safety and performance.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n\u003cul\u003e\n \u003cli\u003ePro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.\u003c\/li\u003e\n \u003cli\u003eFast Global Fulfillment — Free standard delivery to most regions in 5–15 days.\u003c\/li\u003e\n \u003cli\u003eManufacturer-Direct Value — Fair pricing without compromising on materials or QC.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50590215110971,"sku":"27-56108","price":8.99,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/27-56108_ba85f7f1-acd9-457c-91f0-209998ac43ca.jpg?v=1758080317"},{"product_id":"shim-kit-fits-mercruiser-stern-drives-c-r-replaces-15-31535a1","title":"Shim Kit – Fits Mercruiser Stern Drives C.R. (Replaces 15-31535A1)","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; \/* Do not wrap *\/\n word-break:normal; \/* Don’t break words *\/\n letter-spacing:normal; \/* Prevent theme styles from stretching letters *\/\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 aftermarket \u003cstrong\u003eShim Kit – Fits Mercruiser Stern Drives C.R. (Replaces 15-31535A1)\u003c\/strong\u003e is designed for a wide range of Mercruiser stern drive engines manufactured between 1962 and 1977. Compatible models include the 120\/140, 160, 165, 225-S, 233, 250, 470, 888, and 898\/228 series, as well as select Mercury Racing outboards.\u003c\/p\u003e\n\u003cp\u003eThis kit serves as a direct replacement for Mercury\/Mercruiser part number 15-31535A1 and SEI part number 98-108-06K, ensuring precise fitment and function for maintenance or repair.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstallation Location:\u003c\/strong\u003e Mounts between the bearing carrier and the gear housing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBuilt for Marine Use:\u003c\/strong\u003e All components are rated for demanding marine environments.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecise Adjustments:\u003c\/strong\u003e Includes multiple shim thicknesses required for adjusting bearing preload and gear backlash.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n\u003cp\u003eUse this matrix to confirm equivalent references across OEM and aftermarket.\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\u003eMercury\/Mercruiser\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eSEI\u003c\/td\u003e\n \u003ctd\u003e98-108-06K\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 your engine model\/year in the table below.\u003c\/p\u003e\n\u003cp\u003eThis kit is verified for numerous Mercruiser stern drives, Alpha One Gen II counter-rotation models, and specific Mercury Racing\/Mariner outboards as detailed in the compatibility chart.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n \u003ctable class=\"ss-table\" aria-label=\"Engine \u0026amp; Model Compatibility\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth\u003eBrand\u003c\/th\u003e\n \u003cth\u003eModel\u003c\/th\u003e\n \u003cth\u003eRated HP\u003c\/th\u003e\n \u003cth\u003eStroke\u003c\/th\u003e\n \u003cth\u003eYears\u003c\/th\u003e\n \u003cth\u003eOEM Part No.\u003c\/th\u003e\n \u003cth\u003eNotes\u003c\/th\u003e\n \u003c\/tr\u003e\n \u003c\/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e120\/140\u003c\/td\u003e\n \u003ctd\u003e120-140\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1967–1969\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 2062141-2791956\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e120\/140\u003c\/td\u003e\n \u003ctd\u003e120-140\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1970–1977\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 2791957-4893634\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e160\u003c\/td\u003e\n \u003ctd\u003e160\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1967–1969\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 2065190-2763441\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e165\u003c\/td\u003e\n \u003ctd\u003e165\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1970–1977\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 2763442-4890459\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e225-S\u003c\/td\u003e\n \u003ctd\u003e225\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1974\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 3856268-4200499\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e233\u003c\/td\u003e\n \u003ctd\u003e233\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1975–1977\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 4200500 and up\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e250\u003c\/td\u003e\n \u003ctd\u003e250\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1977\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 4791300-4898729\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e470\u003c\/td\u003e\n \u003ctd\u003e170\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1976–1977\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 4208730-4893934\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e888\u003c\/td\u003e\n \u003ctd\u003e188\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1971–1977\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 3106717 and up\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003e898\/228\u003c\/td\u003e\n \u003ctd\u003e228\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1977\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 4782330-4898729\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003eIA\/IB\/IC (EZ-SHIFT)\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1965–1966\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 1776349-2065189\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003eIA\/IB\/IC\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1964\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 1684188-1777798\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003eII (1.78:1)\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1968–1969\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 2398798-2671321\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003eII\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1962–1963\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 1474909-1602185\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003eII\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e4-Stroke\u003c\/td\u003e\n \u003ctd\u003e1964–1967\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 1602186-2278488\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercury Racing\u003c\/td\u003e\n \u003ctd\u003eMERC MOD-VP\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 83B807 and up\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n \u003ctd\u003e2.4L (EFI)\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 0A168043 and below\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n \u003ctd\u003e2.4L (EFI)\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e15-31535A1\u003c\/td\u003e\n \u003ctd\u003eSerial: 0A168044-0B290009\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMercruiser\u003c\/td\u003e\n \u003ctd\u003eAlpha One Generation II Counter Rotation\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003ctd\u003e1991+\u003c\/td\u003e\n \u003ctd\u003e31535A1\u003c\/td\u003e\n \u003ctd\u003eFits SEI Marine Products part 98-108-06K\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\u003eShim Kit\u003c\/dd\u003e\n \u003cdt\u003eInstallation\u003c\/dt\u003e\n\u003cdd\u003eBearing Carrier to Gear Housing\u003c\/dd\u003e\n \u003cdt\u003eHousing Material\u003c\/dt\u003e\n\u003cdd\u003eMetal (likely steel)\u003c\/dd\u003e\n \u003cdt\u003eWorking Pressure\u003c\/dt\u003e\n\u003cdd\u003eMarine environment rated\u003c\/dd\u003e\n \u003cdt\u003eProduct Height\u003c\/dt\u003e\n\u003cdd\u003e0.4\"\u003c\/dd\u003e\n \u003cdt\u003eProduct Width\u003c\/dt\u003e\n\u003cdd\u003e14.0\"\u003c\/dd\u003e\n \u003cdt\u003eProduct Length\u003c\/dt\u003e\n\u003cdd\u003e13.0\"\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 Shim Kit (\u003cspan style=\"color:#d0021b;\"\u003e0.002\", 0.003\", 0.005\", 0.010\" shims\u003c\/span\u003e) (Replaces 15-31535A1)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n \u003cli\u003eEnsure the engine is off and the drive is safely secured before starting work.\u003c\/li\u003e\n \u003cli\u003eDisassemble the lower unit to access the bearing carrier, following your specific model's service manual.\u003c\/li\u003e\n \u003cli\u003eRemove the old bearing carrier and shims, cleaning all mating surfaces thoroughly.\u003c\/li\u003e\n \u003cli\u003eSelect the appropriate combination of new shims from the kit to achieve the required gear backlash and bearing preload. This is a critical step that requires precise measurement with a dial indicator.\u003c\/li\u003e\n \u003cli\u003eInstall the new shims and reinstall the bearing carrier.\u003c\/li\u003e\n \u003cli\u003eTorque all fasteners to the manufacturer's specified values.\u003c\/li\u003e\n \u003cli\u003eReassemble the drive unit, refill with gear lube, and test for proper operation.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\u003csummary\u003eHow do I know if this shim kit will fit my specific Mercruiser model?\u003c\/summary\u003e\u003cp\u003eThe best way to confirm is by checking your engine's serial number against the ranges provided in the Engine \u0026amp; Model Compatibility table. This kit is designed for a broad range of models from 1962–1977 and newer Alpha One Gen II counter-rotation drives.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat is the purpose of this shim kit?\u003c\/summary\u003e\u003cp\u003eThis shim kit is used to set the correct distance and clearance (preload and backlash) for the gears and bearings within the sterndrive's lower unit. Proper shimming is essential for quiet operation, smooth shifting, and preventing premature gear wear.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eAre all the shim thicknesses required for installation?\u003c\/summary\u003e\u003cp\u003eNo. You will use a specific combination of the included shims to achieve the precise measurements required by your drive's service manual. The variety of thicknesses allows for fine-tuned adjustments.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat are signs that my old shims or bearings need replacement?\u003c\/summary\u003e\u003cp\u003eCommon symptoms include a grinding or whining noise from the drive unit, excessive vibration, difficulty shifting, or the presence of metal shavings in the gear lube. These indicate internal wear that may require disassembly and re-shimming.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eIs this kit for standard or counter-rotation drives?\u003c\/summary\u003e\u003cp\u003eThis kit fits a wide array of standard rotation drives from 1962-1977, and it is also explicitly compatible with Mercruiser Alpha One Generation II Counter Rotation models from 1991 and newer.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhy are there different thicknesses included in the kit?\u003c\/summary\u003e\u003cp\u003eThe different thicknesses (0.002\", 0.003\", 0.005\", 0.010\") allow a technician to create the exact total shim stack thickness needed to meet the manufacturer's specification for gear alignment and bearing preload, compensating for manufacturing tolerances in the housing and components.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eOEM vs. Aftermarket?\u003c\/summary\u003e\u003cp\u003eThis listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eShipping speed \u0026amp; cost\u003c\/summary\u003e\u003cp\u003eWe ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWarranty \u0026amp; returns\u003c\/summary\u003e\u003cp\u003eCovered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused \u0026amp; in original condition). See our policy page or reach out for instructions.\u003c\/p\u003e\u003c\/details\u003e\n\n\u003ch2\u003eSafety \u0026amp; Important Info\u003c\/h2\u003e\n\u003cul\u003e\n \u003cli\u003eVerify images\/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.\u003c\/li\u003e\n \u003cli\u003eThis is an aftermarket replacement, not an OEM component.\u003c\/li\u003e\n \u003cli\u003eProfessional installation is recommended for safety and performance.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n\u003cul\u003e\n \u003cli\u003e\n\u003cstrong\u003ePro-Grade Standards\u003c\/strong\u003e — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.\u003c\/li\u003e\n \u003cli\u003e\n\u003cstrong\u003eFast Global Fulfillment\u003c\/strong\u003e — Free standard delivery to most regions in 5–15 days.\u003c\/li\u003e\n \u003cli\u003e\n\u003cstrong\u003eManufacturer-Direct Value\u003c\/strong\u003e — Fair pricing without compromising on materials or QC.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50597935808827,"sku":"15-31535A1","price":19.55,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/15-31535A1_acd02b57-f376-45e4-947b-59a291f34403.jpg?v=1758508272"}],"url":"https:\/\/seasierra.com\/collections\/mercruiser-4-stroke-188hp-marine-engine-parts.oembed","provider":"SeaSierra","version":"1.0","type":"link"}