{"product_id":"sierra-18-0172-oil-seal-for-mercury-mariner-outboards-replaces-oem-26-97530","title":"Sierra Oil Seal 18-0172, Replaces Mercruiser 26-97530, 0.845 Inch Shaft","description":"\u003cp\u003eThe Sierra 18-0172 Oil Seal is a round oil seal engineered as a direct replacement for the Mercruiser 26-97530. It is designed to maintain a reliable barrier against oil and water intrusion at the shaft, keeping lubricants contained and contaminants out for dependable operation. Sierra manufactures this seal to meet or exceed the specifications of the original equipment part it replaces, so it installs and performs the same way as the part it is replacing. The seal features a round profile with a white finish and is sized precisely to a 0.845 inch shaft diameter, 1.500 inch outer diameter, and 0.315 inch width, ensuring a proper fit without modification. This is a single-unit component, sold individually, making it a straightforward swap when servicing a worn or leaking seal. Because it carries the Sierra part number 18-0172 and matches the Mercruiser 26-97530 cross-reference, it is easy to identify and order the correct replacement without guesswork. Marine technicians and boat owners performing routine maintenance or repair on applicable Mercruiser equipment can rely on this seal to restore proper sealing function at the shaft.\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 18-0172\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShaft Size:\u003c\/strong\u003e 0.845 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOuter Diameter:\u003c\/strong\u003e 1.500 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWidth:\u003c\/strong\u003e 0.315 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShape:\u003c\/strong\u003e Round\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor:\u003c\/strong\u003e White\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.03 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 030999751300\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUnit Count:\u003c\/strong\u003e 1\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cp\u003eInterchangeable with Mercruiser 26-97530.\u003c\/p\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\u003cli\u003e26-97530\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat does the Sierra 18-0172 Oil Seal replace?\u003c\/strong\u003e The Sierra 18-0172 Oil Seal is interchangeable with Mercruiser 26-97530, so it can be ordered as a direct replacement for that part number.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the shaft size on this oil seal?\u003c\/strong\u003e The shaft size is 0.845 inches on the Sierra 18-0172 Oil Seal.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat are the outer diameter and width of the 18-0172 seal?\u003c\/strong\u003e The outer diameter is 1.500 inches and the width is 0.315 inches on the Sierra 18-0172 Oil Seal.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the Sierra 18-0172 a genuine Mercruiser part or an aftermarket equivalent?\u003c\/strong\u003e It is a Sierra-manufactured seal, not a Mercruiser-branded part, but Sierra makes it to meet or exceed the specifications of the Mercruiser 26-97530 it replaces.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat shape and color is this oil seal?\u003c\/strong\u003e The Sierra 18-0172 Oil Seal has a round shape and a white finish.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow many seals are included when I order the 18-0172?\u003c\/strong\u003e One unit is included per order of the Sierra 18-0172 Oil Seal.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the Sierra 18-0172 Oil Seal weigh?\u003c\/strong\u003e It weighs 0.03 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill the Sierra 18-0172 seal fit in place of a worn factory seal without modification?\u003c\/strong\u003e Yes, because it is dimensionally matched to the Mercruiser 26-97530 it replaces, the Sierra 18-0172 installs in place of the original seal without modification.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the UPC for the Sierra 18-0172 Oil Seal?\u003c\/strong\u003e The UPC is 030999751300 for the Sierra 18-0172 Oil Seal.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes Sierra warranty the 18-0172 Oil Seal?\u003c\/strong\u003e Yes, the Sierra 18-0172 Oil Seal is covered under Sierra's limited warranty.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988027322587,"sku":"SIE-18-0172","price":13.46,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/SIE-18-0172_lg__91673.1558118066.500.750.jpg?v=1785189080","url":"https:\/\/www.goodvibesmarina.com\/products\/sierra-18-0172-oil-seal-for-mercury-mariner-outboards-replaces-oem-26-97530","provider":"Good Vibes Marina","version":"1.0","type":"link"}