{"product_id":"3486-26-413651-oil-seal-for-mercury-mariner-8hp-9-9hp-15hp-jlm-marine","title":"3486 26-413651 Oil Seal for Mercury Mariner 8HP 9.9HP 15HP | JLM Marine","description":"\u003ch2\u003eOil Seal for Mercury Mariner 8HP 9.9HP 15HP – 26-413651 | JLM Marine\u003c\/h2\u003e\n\n\u003cp\u003eThis \u003cstrong\u003eoil seal\u003c\/strong\u003e is engineered to fit \u003cstrong\u003eMercury Mariner Quicksilver Marine 8hp, 9.9hp, and 15hp (323 cc) 4-Stroke outboard motors\u003c\/strong\u003e. Designed for the lower gearcase unit, this seal ensures reliable protection against oil leaks and maintains optimal lubrication within your outboard's lower unit.\u003c\/p\u003e\n\n\u003cp\u003eThis aftermarket replacement directly supersedes Mercury Marine OEM part numbers \u003cstrong\u003e26-413651\u003c\/strong\u003e and \u003cstrong\u003e18-0581\u003c\/strong\u003e, offering a cost-effective solution without compromising performance or durability.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eDesigned for Mercury Mariner 4-stroke outboard lower gearcase units\u003c\/li\u003e\n  \u003cli\u003eDirect replacement for OEM part numbers 26-413651 and 18-0581\u003c\/li\u003e\n  \u003cli\u003ePrevents oil leaks and ensures proper lower unit lubrication\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Number Cross-Reference\u003c\/h2\u003e\n\n\u003cp\u003eUse this table to confirm equivalent part numbers across OEM and aftermarket brands.\u003c\/p\u003e\n\n\u003ctable border=\"1\" cellpadding=\"8\" cellspacing=\"0\"\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\u003e26-413651\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eSierra\u003c\/td\u003e\n      \u003ctd\u003e18-0581\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eCompatible Engine Models\u003c\/h2\u003e\n\n\u003cp\u003eConfirm your engine model\/year in the table below. For Mercury owners, here's a guide to help you identify your engine's serial\/model: \u003ca href=\"https:\/\/jlmmarine.com\/blogs\/serial-number-guide\/mercury-outboard-serial-number-guide\" rel=\"nofollow noopener\" target=\"_blank\"\u003eMercury Serial Number Guide\u003c\/a\u003e. You can also review exploded diagrams to verify part numbers: \u003ca href=\"https:\/\/jlmmarine.com\/blogs\/diagrams\/mercury-parts-catalog\" rel=\"nofollow noopener\" target=\"_blank\"\u003eMercury Parts Diagrams \u0026amp; Catalog\u003c\/a\u003e.\u003c\/p\u003e\n\n\u003ctable border=\"1\" cellpadding=\"8\" cellspacing=\"0\"\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\u003eEngine Displacement\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eMercury Mariner Quicksilver\u003c\/td\u003e\n      \u003ctd\u003eOutboard Motors\u003c\/td\u003e\n      \u003ctd\u003e8 \/ 9.9 \/ 15 HP\u003c\/td\u003e\n      \u003ctd\u003e4-Stroke\u003c\/td\u003e\n      \u003ctd\u003e323 cc\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\n\u003ctable border=\"1\" cellpadding=\"8\" cellspacing=\"0\"\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n      \u003cth\u003eSpecification\u003c\/th\u003e\n      \u003cth\u003eValue\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd\u003ePart Type\u003c\/td\u003e\n      \u003ctd\u003eOil Seal\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eApplication\u003c\/td\u003e\n      \u003ctd\u003eLower Gearcase Unit\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eOEM Number\u003c\/td\u003e\n      \u003ctd\u003e26-413651, 18-0581\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eCompatible Engines\u003c\/td\u003e\n      \u003ctd\u003eMercury Mariner 8HP, 9.9HP, 15HP (323cc) 4-Stroke\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003ePackage Contents\u003c\/h2\u003e\n\n\u003cp\u003eYour package includes the following:\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\u003cspan style=\"color:red;\"\u003e\u003cstrong\u003e1 × Oil Seal\u003c\/strong\u003e\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003e(The package contains all the parts shown in the product images.)\u003c\/p\u003e\n\n\u003ch2\u003eInstallation Guide\u003c\/h2\u003e\n\n\u003col\u003e\n  \u003cli\u003eDisconnect the outboard motor from the fuel supply and power source. Ensure the lower unit is cool and clean before beginning work.\u003c\/li\u003e\n  \u003cli\u003eDrain the lower unit gear oil completely by removing both the upper vent screw and lower drain plug. Dispose of old oil properly.\u003c\/li\u003e\n  \u003cli\u003eRemove the propeller, propeller shaft, and any retaining hardware to access the lower gearcase seal housing.\u003c\/li\u003e\n  \u003cli\u003eCarefully extract the old oil seal using a seal puller or flat-blade tool. Avoid damaging the seal bore or shaft surface.\u003c\/li\u003e\n  \u003cli\u003eClean the seal bore and shaft thoroughly, removing all residue, old sealant, and debris. Inspect for scratches or corrosion.\u003c\/li\u003e\n  \u003cli\u003eLightly coat the new oil seal's outer diameter and lip with marine-grade grease or lower unit oil.\u003c\/li\u003e\n  \u003cli\u003ePosition the new seal squarely in the bore, ensuring the lip faces inward toward the gear oil. Use a seal driver or socket of appropriate size to press it evenly into place.\u003c\/li\u003e\n  \u003cli\u003eReinstall the propeller shaft, propeller, and all retaining hardware according to manufacturer torque specifications.\u003c\/li\u003e\n  \u003cli\u003eRefill the lower unit with the correct grade and quantity of gear oil through the lower drain hole until oil appears at the upper vent hole.\u003c\/li\u003e\n  \u003cli\u003eInstall the upper vent screw first, then the lower drain plug. Tighten both securely but do not overtighten.\u003c\/li\u003e\n  \u003cli\u003eWipe away any excess oil and inspect for leaks. Run the motor briefly in a test tank and recheck the lower unit for proper oil level and seal integrity.\u003c\/li\u003e\n  \u003cli\u003eDispose of all old seals and oil in accordance with local environmental regulations.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: How do I know if this oil seal fits my Mercury outboard?\u003c\/strong\u003e\u003cbr\u003e\nA: This seal is designed specifically for Mercury Mariner 8hp, 9.9hp, and 15hp (323cc) 4-stroke outboard motors. Verify your engine model using the compatibility table above and cross-check the OEM part numbers (26-413651 or 18-0581) in your service manual or parts diagram.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: What are the signs that my lower unit oil seal needs replacement?\u003c\/strong\u003e\u003cbr\u003e\nA: Common symptoms include visible oil leaking from the lower gearcase, milky or contaminated gear oil indicating water intrusion, unusual noise or vibration from the lower unit, or rapid loss of gear oil between service intervals.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: How often should I replace the lower unit oil seal?\u003c\/strong\u003e\u003cbr\u003e\nA: Oil seals should be inspected during every lower unit oil change (typically every 100 hours or annually). Replace immediately if you notice leaks, damage, or hardening. Preventive replacement every 2–3 years or during major lower unit service is recommended for reliability.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: Can I install this seal myself, or do I need a professional?\u003c\/strong\u003e\u003cbr\u003e\nA: Installation requires basic mechanical skills, appropriate tools (seal puller, driver, torque wrench), and familiarity with lower unit disassembly. If you're inexperienced with outboard service, professional installation is recommended to ensure proper sealing and prevent damage.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: What's the difference between this aftermarket seal and the OEM Mercury part?\u003c\/strong\u003e\u003cbr\u003e\nA: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: How fast do you ship and how much does it cost?\u003c\/strong\u003e\u003cbr\u003e\nA: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: What is your warranty and return policy?\u003c\/strong\u003e\u003cbr\u003e\nA: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused \u0026amp; in original condition); please see our policy page or reach out for instructions.\u003c\/p\u003e\n\n\u003ch2\u003eImportant Notes\u003c\/h2\u003e\n\n\u003cul\u003e\n  \u003cli\u003eVerify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.\u003c\/li\u003e\n  \u003cli\u003eThis product is an aftermarket replacement part and is not an OEM component.\u003c\/li\u003e\n  \u003cli\u003eProfessional installation is recommended to ensure safety and optimal performance.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhy Choose JLM MARINE?\u003c\/h2\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eQuality Assured:\u003c\/strong\u003e As a trusted manufacturer for over 20 years, we supply top marine brands globally.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFast Global Shipping:\u003c\/strong\u003e Free delivery worldwide in 5–15 days.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDirect from Manufacturer:\u003c\/strong\u003e Competitive pricing without compromising quality.\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"JLM Marine","offers":[{"title":"Default Title","offer_id":51983453552953,"sku":"3486","price":18.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0885\/0433\/6697\/files\/3499599_1730687101489.webp?v=1772505162","url":"https:\/\/jlmmarine.com\/ru\/products\/3486-26-413651-oil-seal-for-mercury-mariner-8hp-9-9hp-15hp-jlm-marine","provider":"JLM Marine Boat Parts Limited","version":"1.0","type":"link"}