{"product_id":"lower-unit-seal-kit-fits-johnson-evinrude-85-125-hp-replaces-18-2691-glm-87611-mallory-9-74114","title":"Lower Unit Seal Kit – Fits Johnson\/Evinrude 85-125 HP (Replaces 18-2691, GLM 87611, Mallory 9-74114)","description":"\u003csection\u003e\n\u003ch2\u003eProduct Details\u003c\/h2\u003e\n\u003cp\u003eThis Lower Unit Seal Kit provides the necessary components to restore the gearcase on Johnson and Evinrude 85-125 HP outboard motors with a large prop shaft manufactured between 1971–1972. It is engineered to stop leaks and protect internal gears from water intrusion.\u003c\/p\u003e\n\u003cp\u003eThe kit serves as a direct replacement for several part numbers, including Sierra 18-2691, GLM 87611, and Mallory 9-74114, ensuring broad compatibility for the specified engine models.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstallation:\u003c\/strong\u003e Designed for a direct replacement fit.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication:\u003c\/strong\u003e Suitable for marine outboard motor lower units.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eContents:\u003c\/strong\u003e Includes essential oil seals, O-rings, and gaskets required for a typical reseal job.\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 brands.\u003c\/p\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\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Part Number Cross-Reference\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eBrand\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\u003eSierra\u003c\/td\u003e\n        \u003ctd\u003e18-2691\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eGLM\u003c\/td\u003e\n        \u003ctd\u003e87611\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMallory\u003c\/td\u003e\n        \u003ctd\u003e9-74114\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eQuickMarine\u003c\/td\u003e\n        \u003ctd\u003e18-2691\u003c\/td\u003e\n      \u003c\/tr\u003e\n       \u003ctr\u003e\n        \u003ctd\u003eUanofCn\u003c\/td\u003e\n        \u003ctd\u003e18-2691\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 to ensure accurate fitment.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Engine Model Compatibility\"\u003e\n    \u003cthead\u003e\n      \u003ctr\u003e\n        \u003cth\u003eBrand\u003c\/th\u003e\n        \u003cth\u003eRated HP\u003c\/th\u003e\n        \u003cth\u003eProp Shaft\u003c\/th\u003e\n        \u003cth\u003eYears\u003c\/th\u003e\n        \u003cth\u003eOEM Part No.\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\u003e85 HP\u003c\/td\u003e\n        \u003ctd\u003eLarge Prop Shaft\u003c\/td\u003e\n        \u003ctd\u003e1971–1972\u003c\/td\u003e\n        \u003ctd\u003e18-2691\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eJohnson\/Evinrude\u003c\/td\u003e\n        \u003ctd\u003e100 HP\u003c\/td\u003e\n        \u003ctd\u003eLarge Prop Shaft\u003c\/td\u003e\n        \u003ctd\u003e1971–1972\u003c\/td\u003e\n        \u003ctd\u003e18-2691\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eJohnson\/Evinrude\u003c\/td\u003e\n        \u003ctd\u003e125 HP\u003c\/td\u003e\n        \u003ctd\u003eLarge Prop Shaft\u003c\/td\u003e\n        \u003ctd\u003e1971–1972\u003c\/td\u003e\n        \u003ctd\u003e18-2691\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\u003eLower Unit Gearcase Seal Kit\u003c\/dd\u003e\n  \u003cdt\u003eInstallation\u003c\/dt\u003e\n\u003cdd\u003eDirect replacement\u003c\/dd\u003e\n  \u003cdt\u003ePosition\u003c\/dt\u003e\n\u003cdd\u003eLower unit\u003c\/dd\u003e\n  \u003cdt\u003eApplication\u003c\/dt\u003e\n\u003cdd\u003eMarine outboard motors\u003c\/dd\u003e\n  \u003cdt\u003ePackage Contents\u003c\/dt\u003e\n\u003cdd\u003eOil seals, O-rings, Gaskets\u003c\/dd\u003e\n  \u003cdt\u003ePackage Dimensions\u003c\/dt\u003e\n\u003cdd\u003e150 × 100 × 30 mm (5.91 × 3.94 × 1.18 inches)\u003c\/dd\u003e\n  \u003cdt\u003eWeight\u003c\/dt\u003e\n\u003cdd\u003e0.08 kg (2.82 ounces)\u003c\/dd\u003e\n  \u003cdt\u003eWarranty\u003c\/dt\u003e\n\u003cdd\u003eManufacturer warranty (details vary by brand)\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\u003eOil Seals (Various sizes)\u003c\/li\u003e\n  \u003cli\u003eO-rings (Various sizes)\u003c\/li\u003e\n  \u003cli\u003eGaskets (Various types)\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\u003eDrain the lower unit by removing the upper and lower gear oil drain screws.\u003c\/li\u003e\n    \u003cli\u003eRemove the propeller assembly from the prop shaft.\u003c\/li\u003e\n    \u003cli\u003eUnbolt and carefully remove the gearcase bearing carrier housing.\u003c\/li\u003e\n    \u003cli\u003eTake note of the orientation and position of all old seals and O-rings before removing them.\u003c\/li\u003e\n    \u003cli\u003eThoroughly clean all component surfaces and seal grooves, ensuring they are free of old sealant, dirt, and corrosion.\u003c\/li\u003e\n    \u003cli\u003eLightly lubricate the new seals and O-rings with marine grease before installation to ensure a smooth fit and proper sealing.\u003c\/li\u003e\n    \u003cli\u003eCarefully press the new seals into place, ensuring they are seated evenly and correctly.\u003c\/li\u003e\n    \u003cli\u003eReassemble all components in reverse order of disassembly.\u003c\/li\u003e\n    \u003cli\u003eRefill the lower unit with the manufacturer-specified gear lube.\u003c\/li\u003e\n    \u003cli\u003eFor best results, perform a vacuum and pressure test on the gearcase to confirm there are no leaks before operating the outboard.\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 this kit fits my specific engine model?\u003c\/summary\u003e\n  \u003cp\u003eThis kit is designed for Johnson and Evinrude 85, 100, and 125 HP outboards with a large prop shaft made in 1971 and 1972. Cross-reference your existing part number with those listed in the Part Number Matrix (e.g., Sierra 18-2691, GLM 87611) to ensure compatibility.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat are the common signs of a failing lower unit seal?\u003c\/summary\u003e\n  \u003cp\u003eThe most common symptom is milky or creamy-looking gear lube, which indicates water intrusion. You may also notice gear oil leaking from the prop shaft area or around the drain\/fill screw seals.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow often should lower unit seals be replaced?\u003c\/summary\u003e\n  \u003cp\u003eThere is no fixed replacement interval, but it's good practice to inspect the gear lube for water at every oil change. Seals should be replaced immediately if a leak is detected, or as preventative maintenance on older engines, especially those used in saltwater.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eDoes this kit include all the seals for the entire lower unit?\u003c\/summary\u003e\n  \u003cp\u003eThis kit contains the primary seals, gaskets, and O-rings for the lower unit gearcase area, including the prop shaft and bearing carrier. However, it may not include every possible seal, such as those for the water pump or shift shaft, which are often sold in separate kits.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eIs professional installation necessary?\u003c\/summary\u003e\n  \u003cp\u003eWhile DIY installation is possible for mechanically inclined individuals with the correct tools (like a bearing carrier puller), we recommend professional installation to ensure all seals are seated correctly and a pressure test can be performed to guarantee a leak-free repair.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat's the difference between aftermarket and OEM parts?\u003c\/summary\u003e\n  \u003cp\u003eThis listing is for an aftermarket replacement, not an original equipment manufacturer (OEM) part. It is engineered to meet or exceed OEM specifications using comparable materials and is manufactured in modern, quality-controlled facilities. It offers a cost-effective alternative without sacrificing performance.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat are your shipping speed and cost?\u003c\/summary\u003e\n  \u003cp\u003eWe ship worldwide quickly—typical transit is 5–15 days. Standard shipping is free to most locations, with expedited options available at checkout where applicable.\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 an issue, please contact our support team with your order details. Returns are accepted within our standard window for unused items in their original condition. See our 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 purchase. If anything differs—even if your model appears compatible—do not install.\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 to ensure optimal performance.\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 conditions.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFast Global Fulfillment\u003c\/strong\u003e — Free standard delivery to most regions, typically arriving in 5–15 days.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer-Direct Value\u003c\/strong\u003e — We offer fair pricing by eliminating middlemen, 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":50718257774907,"sku":"QM-OSK24706","price":28.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/QM-OSK24706.png?v=1762958231","url":"https:\/\/seasierra.com\/products\/lower-unit-seal-kit-fits-johnson-evinrude-85-125-hp-replaces-18-2691-glm-87611-mallory-9-74114","provider":"SeaSierra","version":"1.0","type":"link"}