{"product_id":"sierra-18-2673-upper-unit-seal-kit-replaces-omc-984459-fits-all-omc-cobra-sterndrive-1986-1989","title":"Sierra 18-2673 Upper Unit Seal Kit, Replaces 984459 986364 987603, for All Cobra (1986-89) OMC Sterndrive","description":"\u003cp\u003eThe Sierra 18-2673 Upper Unit Seal Kit is a seal set engineered for the upper gearcase unit on All Cobra (1986-89) OMC sterndrive applications. It is built to replace the OEM upper unit seals that wear out over time from heat, vibration, and constant exposure to water and gear lubricant, restoring a proper seal against water intrusion and lubricant loss in the upper drive unit. This kit is a direct cross-reference for OMC OEM part numbers 984459, 986364, and 987603, so it installs as a like-for-like replacement without modification to the drive unit.\u003c\/p\u003e\u003cp\u003eThis is a seal kit specifically for the upper unit of the sterndrive, distinct from the companion 18-2674 Transom Mount Seal Kit, which is a separate part number covering a different section of the drive. Ordering the correct kit for the section of the drive being serviced ensures the right seals are on hand for the job. The kit weighs 0.24 pounds as packaged.\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 18-2673\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Name:\u003c\/strong\u003e Upper Unit Seal Kit\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e OMC Bellows and Transom Seal\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.24 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 808282258023\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReplaces (OEM):\u003c\/strong\u003e 984459, 986364, 987603\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFitment:\u003c\/strong\u003e All Cobra (1986-89)\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cul\u003e\u003cli\u003eAll Cobra (1986-89) OMC Sterndrive\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e984459\u003c\/li\u003e\n\u003cli\u003e986364\u003c\/li\u003e\n\u003cli\u003e987603\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat does the Sierra 18-2673 Upper Unit Seal Kit fit?\u003c\/strong\u003e The Sierra 18-2673 Upper Unit Seal Kit fits All Cobra (1986-89) OMC sterndrive applications.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhich OEM part numbers does the 18-2673 replace?\u003c\/strong\u003e Sierra 18-2673 replaces OMC OEM part numbers 984459, 986364, and 987603.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the 18-2673 seal kit weigh?\u003c\/strong\u003e The Sierra 18-2673 Upper Unit Seal Kit weighs 0.24 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the 18-2673 kit the same as the 18-2674 kit?\u003c\/strong\u003e No, 18-2673 is the Upper Unit Seal Kit while 18-2674 is the Transom Mount Seal Kit, a separate part number for a different section of the same Cobra sterndrive application.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill this kit work on any OMC sterndrive?\u003c\/strong\u003e The 18-2673 kit is designated for All Cobra (1986-89) applications; it is not listed as fitting other OMC sterndrive models.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs Sierra 18-2673 a genuine OEM part or aftermarket?\u003c\/strong\u003e Sierra 18-2673 is a Sierra-branded replacement part manufactured as a cross-reference equivalent to OMC OEM numbers 984459, 986364, and 987603.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat section of the drive does the 18-2673 kit service?\u003c\/strong\u003e The 18-2673 kit contains seals for the upper unit (upper gearcase) of the Cobra sterndrive, as opposed to the transom mount section covered by 18-2674.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhy would I need to replace these seals?\u003c\/strong\u003e Upper unit seals in the Cobra sterndrive wear from heat, vibration, and constant exposure to water and gear lubricant, and the 18-2673 kit provides the replacement seals needed to restore a proper seal.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I order 18-2673 by its UPC code?\u003c\/strong\u003e Yes, the Sierra 18-2673 Upper Unit Seal Kit carries UPC 808282258023.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the 18-2673 kit include installation instructions?\u003c\/strong\u003e The dossier for the 18-2673 Upper Unit Seal Kit does not specify included instructions; it is sold as the seal kit itself.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988108685531,"sku":"SIE-18-2673","price":56.59,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/SIE-18-2673_lg__57195.1558122790.500.750.jpg?v=1785188004","url":"https:\/\/www.goodvibesmarina.com\/products\/sierra-18-2673-upper-unit-seal-kit-replaces-omc-984459-fits-all-omc-cobra-sterndrive-1986-1989","provider":"Good Vibes Marina","version":"1.0","type":"link"}