{"product_id":"gearcase-lower-unit-seal-kit-fits-johnson-evinrude-8-15-hp-replaces-0396350-0777568","title":"Gearcase Lower Unit Seal Kit – Fits Johnson\/Evinrude 8–15 HP (Replaces 0396350, 0777568)","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 complete aftermarket \u003cstrong\u003eGearcase Lower Unit Seal Kit – Fits Johnson\/Evinrude 8–15 HP Outboards\u003c\/strong\u003e contains all necessary seals, o-rings, and hardware to rebuild the lower unit on Johnson\/Evinrude 8–15 HP 2-Stroke (1974–2007) and 4-Stroke (1995–2004) outboard motors.\u003c\/p\u003e\n\u003cp\u003eIt serves as a direct replacement for OEM part numbers 0396350 and 0777568, and interchanges with aftermarket references including Sierra 18-2656, GLM 87602, and Mallory 9-74100.\u003c\/p\u003e\n\u003cul\u003e\n    \u003cli\u003eRestores sealing integrity to prevent water intrusion and oil leaks.\u003c\/li\u003e\n    \u003cli\u003eIncludes a comprehensive set of components for a standard lower unit reseal.\u003c\/li\u003e\n    \u003cli\u003eProfessional installation is recommended for optimal performance and longevity.\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 suppliers.\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\u003c\/td\u003e\n        \u003ctd\u003e0396350\u003c\/td\u003e\n        \u003ctd\u003eSuperseded by 0777568\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eJohnson\/Evinrude\u003c\/td\u003e\n        \u003ctd\u003e0777568\u003c\/td\u003e\n        \u003ctd\u003eCurrent OEM Part Number\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eSierra\u003c\/td\u003e\n        \u003ctd\u003e18-2656\u003c\/td\u003e\n        \u003ctd\u003eAftermarket\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eGLM\u003c\/td\u003e\n        \u003ctd\u003e87602\u003c\/td\u003e\n        \u003ctd\u003eAftermarket\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMallory Marine\u003c\/td\u003e\n        \u003ctd\u003e9-74100\u003c\/td\u003e\n        \u003ctd\u003eAftermarket\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eSEI Marine\u003c\/td\u003e\n        \u003ctd\u003e95-361-11K\u003c\/td\u003e\n        \u003ctd\u003eAftermarket\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eQuickMarine\u003c\/td\u003e\n        \u003ctd\u003e396350\u003c\/td\u003e\n        \u003ctd\u003eAftermarket\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMhrxusd\u003c\/td\u003e\n        \u003ctd\u003e0396350\u003c\/td\u003e\n        \u003ctd\u003eAftermarket\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 and year in the table below. This kit is designed for a wide range of Johnson and Evinrude 2-stroke and 4-stroke motors from 8 to 15 HP.\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\u003eMultiple\u003c\/td\u003e\n        \u003ctd\u003e8\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1995–2004\u003c\/td\u003e\n        \u003ctd\u003e0396350\/0777568\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\u003eMultiple\u003c\/td\u003e\n        \u003ctd\u003e9.9\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1974–2007\u003c\/td\u003e\n        \u003ctd\u003e0396350\/0777568\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\u003eMultiple\u003c\/td\u003e\n        \u003ctd\u003e9.9\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1995–2004\u003c\/td\u003e\n        \u003ctd\u003e0396350\/0777568\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\u003eMultiple\u003c\/td\u003e\n        \u003ctd\u003e10\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1974–2007\u003c\/td\u003e\n        \u003ctd\u003e0396350\/0777568\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\u003eMultiple\u003c\/td\u003e\n        \u003ctd\u003e15\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1974–2007\u003c\/td\u003e\n        \u003ctd\u003e0396350\/0777568\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\u003eMultiple\u003c\/td\u003e\n        \u003ctd\u003e15\u003c\/td\u003e\n        \u003ctd\u003e4-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1995–2004\u003c\/td\u003e\n        \u003ctd\u003e0396350\/0777568\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\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\u003eProfessional recommended\u003c\/dd\u003e\n  \u003cdt\u003eWeight\u003c\/dt\u003e\n\u003cdd\u003e0.068 kg (2.4 oz)\u003c\/dd\u003e\n  \u003cdt\u003eWarranty\u003c\/dt\u003e\n\u003cdd\u003e1-year against manufacturing defects\u003c\/dd\u003e\n  \u003cdt\u003eOther Technical Attributes\u003c\/dt\u003e\n\u003cdd\u003eISO 9001\/9002 certified manufacturing (aftermarket)\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 Oil Seal (0318972)\u003c\/li\u003e\n    \u003cli\u003e1 x Oil Seal (0321480)\u003c\/li\u003e\n    \u003cli\u003e1 x Oil Seal (0342247)\u003c\/li\u003e\n    \u003cli\u003e1 x Drain\/Fill Plug Washer (0311598)\u003c\/li\u003e\n    \u003cli\u003e1 x O-Ring (0301877)\u003c\/li\u003e\n    \u003cli\u003e1 x O-Ring (0308627)\u003c\/li\u003e\n    \u003cli\u003e1 x O-Ring (0307853)\u003c\/li\u003e\n    \u003cli\u003e1 x O-Ring (0319085)\u003c\/li\u003e\n    \u003cli\u003e1 x Washer (0332584)\u003c\/li\u003e\n    \u003cli\u003e1 x Fill and Drain Plug Screw (0307551)\u003c\/li\u003e\n    \u003cli\u003e1 x Shift Rod Washer (0321738)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n    \u003cli\u003eDisconnect the battery and spark plug wires for safety.\u003c\/li\u003e\n    \u003cli\u003eDrain the gearcase oil by removing the lower and upper drain\/fill plugs. Inspect oil for water (milky) or metal shavings.\u003c\/li\u003e\n    \u003cli\u003eRemove the propeller and associated hardware.\u003c\/li\u003e\n    \u003cli\u003eUnbolt and carefully separate the lower unit (gearcase) from the outboard's upper housing. The shift linkage may need to be disconnected.\u003c\/li\u003e\n    \u003cli\u003eDisassemble components as required to access the seals, including the water pump housing and bearing carriers. Keep parts organized.\u003c\/li\u003e\n    \u003cli\u003eCarefully remove all old seals, o-rings, and gaskets using appropriate pullers to avoid scratching metal surfaces.\u003c\/li\u003e\n    \u003cli\u003eThoroughly clean all sealing surfaces and component housings, removing any old sealant, corrosion, or debris.\u003c\/li\u003e\n    \u003cli\u003eInstall the new seals and o-rings from the kit. Lightly lubricate new seals with marine grease to ease installation.\u003c\/li\u003e\n    \u003cli\u003eReassemble the gearcase, ensuring all bolts are torqued to manufacturer specifications.\u003c\/li\u003e\n    \u003cli\u003eReattach the lower unit, ensuring the driveshaft, water tube, and shift shaft are correctly aligned.\u003c\/li\u003e\n    \u003cli\u003eRefill the gearcase with new marine gear lubricant. Reinstall both drain\/fill plugs with new washers.\u003c\/li\u003e\n    \u003cli\u003eReinstall the propeller and test the engine in a water source, checking for leaks after 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 my gearcase seals are failing?\u003c\/summary\u003e\u003cp\u003eCommon signs include milky, water-contaminated gear oil (check via the drain plug), visible oil leaks around the propeller shaft or gearcase seams, or a frequent need to top off gear lube without visible leaks.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWill this kit fit my specific engine model?\u003c\/summary\u003e\u003cp\u003eThis kit fits the HP and year ranges specified in the compatibility table. For a guaranteed match, always verify your engine’s OEM part number against those listed (0396350, 0777568) before ordering.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eIs professional installation really necessary?\u003c\/summary\u003e\u003cp\u003eWhile DIY installation is possible for experienced mechanics, we strongly recommend professional installation. Improper seating or damage to a seal during installation can cause premature failure and lead to catastrophic gearcase damage.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eHow often should gearcase seals be replaced?\u003c\/summary\u003e\u003cp\u003eInspect your gear lube at least once a season. Seals should be replaced immediately if you notice any leaks or water contamination. As preventative maintenance, consider replacement every 5–7 years, depending on usage and operating conditions.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eWhat is the most common cause of gearcase seal failure?\u003c\/summary\u003e\u003cp\u003eThe leading cause of premature failure is damage from fishing line or other debris wrapping around the propeller shaft, which cuts into the seal and allows water to enter. Normal wear and age are also factors.\u003c\/p\u003e\u003c\/details\u003e\n\u003cdetails\u003e\u003csummary\u003eCan I reuse any of the old seals or gaskets?\u003c\/summary\u003e\u003cp\u003eNo. Always use all new seals, o-rings, and washers provided in the kit. Old components can be hardened, cracked, or deformed and will not create a reliable, long-lasting seal.\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). It is built to OEM-level specifications with comparable materials. Our parts are manufactured in an ISO 9002 facility and are 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 is 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\u003eThis product is covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact our support team with your order details. Returns are accepted within our standard window for unused items 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 and specifications against your original part before purchase. If anything differs—even if your model appears compatible—do not purchase.\u003c\/li\u003e\n    \u003cli\u003eThis is an aftermarket replacement component, not an OEM part.\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\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 — We offer free standard delivery to most regions, with typical transit times of 5–15 days.\u003c\/li\u003e\n    \u003cli\u003eManufacturer-Direct Value — Our direct-sourcing model provides fair 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":50717909156155,"sku":"SS-24OSK704","price":35.99,"currency_code":"USD","in_stock":true}],"url":"https:\/\/seasierra.com\/products\/gearcase-lower-unit-seal-kit-fits-johnson-evinrude-8-15-hp-replaces-0396350-0777568","provider":"SeaSierra","version":"1.0","type":"link"}