{"product_id":"sierra-18-7117-marine-o-ring-replaces-omc-303360-mercruiser-25-35027-fits-johnson-evinrude-omc-mercruiser-mercury","title":"Sierra 18-7117 O-Ring, Replaces 25-35027, for OMC Sterndrive and Cobra Stern Drives","description":"\u003cp\u003eThe Sierra 18-7117 is a marine-grade rubber O-ring engineered as a direct replacement seal for select OMC Sterndrive and Cobra stern drive applications, and is also used across select Johnson\/Evinrude, Mercruiser, and Mercury Marine engines. It measures 1.046 inches (26.6mm) in inside diameter with a 0.135 inch (3.4mm) width, sized to seat correctly in the original bore and provide a reliable fluid seal at its mounting location. The O-ring is molded from rubber for resistance to the fuel, oil, and water exposure common in sterndrive and outboard drive components, helping prevent leaks and drips at gasket and housing joints. Each package contains one O-ring, so buyers can order the exact quantity needed for a single repair without paying for a larger multi-pack. As a Sierra part, the 18-7117 is built to meet or exceed the specifications of the original equipment part it replaces, making it a straightforward drop-in choice when resealing sterndrive housings or related components. It carries the manufacturer's O.E. Cross-reference number 25-35027, so it can be matched confidently against the original part being replaced. This O-ring is a small, low-cost component, but a proper fit and quality rubber compound are essential to preventing seal failure and fluid leakage in marine drive systems.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Sierra\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number:\u003c\/strong\u003e 18-7117\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Rubber\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInside Diameter:\u003c\/strong\u003e 1.046 inches (26.6mm)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWidth:\u003c\/strong\u003e 0.135 inches (3.4mm)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUnit Count:\u003c\/strong\u003e 1 O-ring per package\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.01 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM Cross Reference:\u003c\/strong\u003e 25-35027\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cp\u003eDesigned for use in select OMC Sterndrive and Cobra stern drive applications, and also used in select Johnson\/Evinrude, Mercruiser, and Mercury Marine engines.\u003c\/p\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\u003cli\u003e25-35027\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat is the inside diameter and width of the Sierra 18-7117 O-ring?\u003c\/strong\u003e The Sierra 18-7117 has a 1.046 inch (26.6mm) inside diameter and a 0.135 inch (3.4mm) width.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat does the Sierra 18-7117 O-ring replace?\u003c\/strong\u003e It replaces OEM part number 25-35027, and is engineered as a direct-fit substitute for that original seal.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat engines and drives is the 18-7117 O-ring used on?\u003c\/strong\u003e This O-ring is used in select OMC Sterndrive and Cobra stern drive applications, and also fits select Johnson\/Evinrude, Mercruiser, and Mercury Marine engines.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow many O-rings come in a package?\u003c\/strong\u003e Each package of the Sierra 18-7117 contains one O-ring.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat material is the 18-7117 O-ring made from?\u003c\/strong\u003e It is molded from rubber, suited to sealing against fuel, oil, and water exposure in marine drive components.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the Sierra 18-7117 a genuine OEM part or an aftermarket replacement?\u003c\/strong\u003e The 18-7117 is a Sierra aftermarket replacement O-ring built to meet or exceed the specifications of the original 25-35027 part it replaces.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the 18-7117 O-ring weigh?\u003c\/strong\u003e The Sierra 18-7117 O-ring weighs 0.01 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I use the 18-7117 O-ring on a Mercury Marine drive?\u003c\/strong\u003e Yes, the 18-7117 is used in select Mercury Marine engines in addition to OMC Sterndrive, Cobra, Johnson\/Evinrude, and Mercruiser applications.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow do I confirm the Sierra 18-7117 is the correct O-ring for my repair?\u003c\/strong\u003e Match it against the O.E. Number 25-35027 on your original part, or confirm your engine or drive is one of the OMC Sterndrive, Cobra, Johnson\/Evinrude, Mercruiser, or Mercury Marine applications this O-ring is designed for.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhere is the 18-7117 O-ring typically installed?\u003c\/strong\u003e It is used as a sealing O-ring within OMC Sterndrive and Cobra stern drive housings and related components on the compatible engines listed for this part.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988364112091,"sku":"SIE-18-7117","price":1.19,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/18-7117__59948.1722500199.500.750.jpg?v=1785188152","url":"https:\/\/www.goodvibesmarina.com\/products\/sierra-18-7117-marine-o-ring-replaces-omc-303360-mercruiser-25-35027-fits-johnson-evinrude-omc-mercruiser-mercury","provider":"Good Vibes Marina","version":"1.0","type":"link"}