{"product_id":"lower-unit-gearcase-seal-kit-fits-johnson-evinrude-40hp-48hp-50hp-2-stroke-outboards-replaces-433550-0777551","title":"Lower Unit Gearcase Seal Kit – Fits Johnson\/Evinrude 40HP, 48HP \u0026 50HP 2-Stroke Outboards (Replaces 433550, 0777551)","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 \u003cstrong\u003eLower Unit Gearcase Seal Kit\u003c\/strong\u003e is designed to service the gearcases of Johnson and Evinrude 40HP, 48HP, and 50HP 2-stroke outboard engines manufactured from 1989 to 2005. It provides all necessary seals and gaskets to restore watertight integrity and prevent leaks.\u003c\/p\u003e\n \u003cp\u003eThe kit serves as a direct interchange for several OEM and aftermarket part numbers, including Sierra 18-2694, GLM 87614, and Mallory 9-74104.\u003c\/p\u003e\n \u003cul\u003e\n \u003cli\u003eInstalls as a direct OEM-equivalent replacement.\u003c\/li\u003e\n \u003cli\u003eIncludes a complete set of seals, O-rings, and gaskets for a full service.\u003c\/li\u003e\n \u003cli\u003eBuilt from durable rubber and metal components to withstand the marine environment.\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 \u003cth\u003eNotes\u003c\/th\u003e\n \u003c\/tr\u003e\n \u003c\/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003eJohnson\/Evinrude (OEM)\u003c\/td\u003e\n \u003ctd\u003e433550\u003c\/td\u003e\n \u003ctd\u003ePrimary interchange\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eJohnson\/Evinrude (OEM)\u003c\/td\u003e\n \u003ctd\u003e0777551\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eSierra\u003c\/td\u003e\n \u003ctd\u003e18-2694\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eGLM\u003c\/td\u003e\n \u003ctd\u003e87614\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eMallory\u003c\/td\u003e\n \u003ctd\u003e9-74104\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eSeaSierra\u003c\/td\u003e\n \u003ctd\u003e433550\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eJUWEVAZU\u003c\/td\u003e\n \u003ctd\u003e433550\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eGHmarine\u003c\/td\u003e\n \u003ctd\u003e433550\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eRed Rhino\u003c\/td\u003e\n \u003ctd\u003eJE-270\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eEMP\u003c\/td\u003e\n \u003ctd\u003e26-07400\u003c\/td\u003e\n \u003ctd\u003e\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 Johnson\/Evinrude owners, this kit covers a wide range of 2-stroke models. Pay close attention to horsepower, year, and specific notes to ensure a correct 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\u003eJohnson\/Evinrude\u003c\/td\u003e\n \u003ctd\u003eVarious\u003c\/td\u003e\n \u003ctd\u003e25\u003c\/td\u003e\n \u003ctd\u003e2-Stroke\u003c\/td\u003e\n \u003ctd\u003e1990–1995\u003c\/td\u003e\n \u003ctd\u003e433550\u003c\/td\u003e\n \u003ctd\u003eD suffix only\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eJohnson\/Evinrude\u003c\/td\u003e\n \u003ctd\u003eVarious\u003c\/td\u003e\n \u003ctd\u003e40\u003c\/td\u003e\n \u003ctd\u003e2-Stroke\u003c\/td\u003e\n \u003ctd\u003e1989 \u0026amp; Up\u003c\/td\u003e\n \u003ctd\u003e433550\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eJohnson\/Evinrude\u003c\/td\u003e\n \u003ctd\u003eVarious\u003c\/td\u003e\n \u003ctd\u003e48\u003c\/td\u003e\n \u003ctd\u003e2-Stroke\u003c\/td\u003e\n \u003ctd\u003e1989–1996\u003c\/td\u003e\n \u003ctd\u003e433550\u003c\/td\u003e\n \u003ctd\u003e\u003c\/td\u003e\n \u003c\/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003eJohnson\/Evinrude\u003c\/td\u003e\n \u003ctd\u003eVarious\u003c\/td\u003e\n \u003ctd\u003e50\u003c\/td\u003e\n \u003ctd\u003e2-Stroke\u003c\/td\u003e\n \u003ctd\u003e1989 \u0026amp; Up\u003c\/td\u003e\n \u003ctd\u003e433550\u003c\/td\u003e\n \u003ctd\u003eIncludes 1987 50HP gearbox applications\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\u003eLower Unit Gearcase Seal Kit\u003c\/dd\u003e\n \u003cdt\u003eInstallation\u003c\/dt\u003e\n \u003cdd\u003eDirect OEM Replacement\u003c\/dd\u003e\n \u003cdt\u003eHousing Material\u003c\/dt\u003e\n \u003cdd\u003eRubber, Metal\u003c\/dd\u003e\n \u003cdt\u003eHousing Color\u003c\/dt\u003e\n \u003cdd\u003eBlack\u003c\/dd\u003e\n \u003cdt\u003eWarranty\u003c\/dt\u003e\n \u003cdd\u003e1 Year (GHmarine)\u003c\/dd\u003e\n \u003cdt\u003eOther Technical Attributes\u003c\/dt\u003e\n \u003cdd\u003eComplete kit containing all necessary seals, O-rings, and gaskets for lower unit service\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 Gearcase Seal Kit (\u003cspan style=\"color:#d0021b;\"\u003econtains approximately 20 pieces\u003c\/span\u003e)\u003c\/li\u003e\n \u003cli\u003e1 x Installation Instructions\u003c\/li\u003e\n \u003c\/ul\u003e\n\n \u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n \u003col\u003e\n \u003cli\u003ePosition a drain pan under the lower unit and remove the upper and lower gear lube drain screws to empty the old oil.\u003c\/li\u003e\n \u003cli\u003eRemove the propeller and shift the outboard into neutral.\u003c\/li\u003e\n \u003cli\u003eUnbolt and carefully detach the lower unit (gearcase) from the outboard's midsection.\u003c\/li\u003e\n \u003cli\u003eDisassemble the gearcase components, including the water pump, driveshaft, and propeller shaft, taking photos to remember the order.\u003c\/li\u003e\n \u003cli\u003eCarefully pry out all old seals, O-rings, and gaskets from the housing and shafts. Avoid scratching the metal surfaces.\u003c\/li\u003e\n \u003cli\u003eThoroughly clean all sealing surfaces with a suitable solvent to remove any old sealant, corrosion, or debris.\u003c\/li\u003e\n \u003cli\u003eLightly lubricate the new seals and O-rings with 2-4-C marine grease before installation.\u003c\/li\u003e\n \u003cli\u003eUsing appropriate seal drivers or sockets, press the new seals into place until they are fully seated.\u003c\/li\u003e\n \u003cli\u003eReassemble all components in reverse order of disassembly, ensuring correct alignment.\u003c\/li\u003e\n \u003cli\u003eReinstall the lower unit onto the outboard, tightening bolts to manufacturer torque specifications.\u003c\/li\u003e\n \u003cli\u003eRefill the gearcase with fresh, high-quality marine gear lubricant until it flows from the upper vent hole.\u003c\/li\u003e\n \u003cli\u003eReinstall the vent and drain screws with new washers\/seals from the kit, and check for leaks after a short period.\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 this seal kit will fit my engine?\u003c\/summary\u003e\n \u003cp\u003eThis kit is specifically for Johnson\/Evinrude 40HP, 48HP, and 50HP 2-stroke outboards (1989–2005). The most reliable way to confirm fitment is to match your original part number to one listed in our Part Number Matrix. If uncertain, please contact us with your engine's model and serial number before purchasing.\u003c\/p\u003e\n \u003c\/details\u003e\n \u003cdetails\u003e\n \u003csummary\u003eWhat are the signs of a failing gearcase seal?\u003c\/summary\u003e\n \u003cp\u003eThe most common symptom is milky, grey, or creamy-looking gear lube, which indicates water contamination. Other signs include visible oil leaks around the propeller shaft, driveshaft, or drain screws, and in severe cases, a burning smell or grinding noises from the lower unit.\u003c\/p\u003e\n \u003c\/details\u003e\n \u003cdetails\u003e\n \u003csummary\u003eHow often should I replace my lower unit seals?\u003c\/summary\u003e\n \u003cp\u003eIt is recommended to inspect lower unit seals annually during routine maintenance (like a water pump service). Proactive replacement is advised every 3-5 years, or immediately if you find evidence of water intrusion or oil leakage.\u003c\/p\u003e\n \u003c\/details\u003e\n \u003cdetails\u003e\n \u003csummary\u003eAre the components in this kit identical to the OEM version?\u003c\/summary\u003e\n \u003cp\u003eThis kit is engineered to be a direct functional replacement and includes all the necessary seals, O-rings, and gaskets for a standard lower unit reseal on the specified models. While component materials and manufacturing processes are comparable to OEM standards, the exact contents may differ slightly from a factory kit, but all critical parts for the application are included.\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\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":50723801465147,"sku":"KF23SK602","price":33.45,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/KF23SK602.png?v=1763032193","url":"https:\/\/seasierra.com\/products\/lower-unit-gearcase-seal-kit-fits-johnson-evinrude-40hp-48hp-50hp-2-stroke-outboards-replaces-433550-0777551","provider":"SeaSierra","version":"1.0","type":"link"}