{"product_id":"sierra-18-0579-oil-seal-replaces-mercury-force-26-41131-mercury-outboard-powerhead-seal","title":"Sierra Oil Seal 18-0579, Replaces Mercury 26-41131, White","description":"\u003cp\u003eThe Sierra 18-0579 Oil Seal is a rubber powerhead seal engineered to seal rotating shafts against oil and water intrusion in marine outboard and sterndrive powerheads. It is built to meet or exceed the specifications of the original equipment part it replaces, making it a reliable direct-fit choice for engine rebuilds and routine seal replacement. The seal is molded in white rubber and sized to a 1.313 inch outer diameter, a 1.141 inch shaft size, and a 0.344 inch width, allowing it to seat correctly in the powerhead bore while maintaining a tight, low-friction fit against the shaft. As a wear item, this seal is commonly replaced during powerhead teardowns, gearcase service, or whenever oil seepage is found around the shaft. It cross-references directly to Mercury and Chrysler\/Force\/US Marine part number 26-41131, giving buyers a straightforward way to confirm fit against their original part number before ordering.\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 18-0579\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Type:\u003c\/strong\u003e Oil Seal\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Rubber\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor:\u003c\/strong\u003e White\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOuter Diameter:\u003c\/strong\u003e 1.313 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShaft Size:\u003c\/strong\u003e 1.141 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWidth:\u003c\/strong\u003e 0.344 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.04 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM Cross Reference:\u003c\/strong\u003e 26-41131\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cp\u003eDirect cross-reference to Mercury and Chrysler\/Force\/US Marine part number 26-41131; confirm against your original part number before ordering.\u003c\/p\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\u003cli\u003e26-41131\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat does the Sierra 18-0579 Oil Seal replace?\u003c\/strong\u003e The Sierra 18-0579 Oil Seal is a direct cross-reference to Mercury and Chrysler\/Force\/US Marine part number 26-41131.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat are the dimensions of the 18-0579 seal?\u003c\/strong\u003e This seal measures 1.313 inches outer diameter, 1.141 inches shaft size, and 0.344 inches in width.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat material is the 18-0579 Oil Seal made from?\u003c\/strong\u003e It is molded from rubber for durable sealing against oil and water in marine powerheads.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat color is the Sierra 18-0579 seal?\u003c\/strong\u003e The 18-0579 seal is white.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the Sierra 18-0579 Oil Seal weigh?\u003c\/strong\u003e This seal weighs 0.04 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the Sierra 18-0579 seal equivalent to the original equipment part?\u003c\/strong\u003e Yes, Sierra states this oil seal meets or exceeds the original equipment part it replaces, part number 26-41131.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhere is the 18-0579 seal typically installed?\u003c\/strong\u003e It is installed in the powerhead bore to seal a rotating shaft, and is commonly replaced during powerhead or gearcase service.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow many seals come in an order of 18-0579?\u003c\/strong\u003e The Sierra 18-0579 Oil Seal is supplied as a single unit.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy would I need to replace this seal?\u003c\/strong\u003e Oil seepage or leakage around the shaft during a powerhead teardown is the typical reason to replace the 18-0579 seal.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the 18-0579 seal fit non-Mercury applications?\u003c\/strong\u003e It cross-references to Mercury and Chrysler\/Force\/US Marine 26-41131, so any application originally using 26-41131 is a match.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988082045147,"sku":"SIE-18-0579","price":14.21,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/18-0579__39305.1722346079.500.750.jpg?v=1785188923","url":"https:\/\/www.goodvibesmarina.com\/products\/sierra-18-0579-oil-seal-replaces-mercury-force-26-41131-mercury-outboard-powerhead-seal","provider":"Good Vibes Marina","version":"1.0","type":"link"}