{"product_id":"upper-unit-seal-kit-18-2643-replaces-mercruiser-26-16709a2-for-bravo-blackhawk-upper-gear-housing","title":"Sierra 18-2643 Upper Unit Seal Kit for MerCruiser Bravo II X, Bravo III, Bravo III X and Blackhawk Drives","description":"\u003cp\u003eThe Sierra 18-2643 Upper Unit Seal Kit is a replacement seal set for the upper gear housing of MerCruiser Bravo II X, Bravo III, Bravo III X, and Blackhawk sterndrive units. This kit addresses the seals responsible for keeping gear lubricant contained and water out of the upper unit, a common service point during routine outdrive maintenance or when diagnosing gear housing leaks. Each kit ships as a complete set (one kit per package) so the seals can be replaced together during a single service interval, rather than sourcing individual seals separately.\u003c\/p\u003e\u003cp\u003eSierra manufactures this kit to meet or exceed the specifications of the original equipment seals it replaces, making it a direct equivalent for the applicable MerCruiser upper units. The kit fits specific serial-number ranges on the Bravo II X, Bravo III, Bravo III X, and Blackhawk drives, so confirming the drive model and serial number before ordering ensures the correct fit. As with all Sierra parts, this kit is backed by Sierra's standard limited warranty.\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 18-2643\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e MerCruiser Upper Gear Housing Seal Kit\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.19 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor:\u003c\/strong\u003e White\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShape:\u003c\/strong\u003e Round\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 030999875204\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFitment:\u003c\/strong\u003e MerCruiser Bravo II X, Bravo III, Bravo III X, Blackhawk\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM Cross Reference:\u003c\/strong\u003e GLM 87480, Mallory 9-74301, Mercruiser 26-16709A1, 27-16709A2\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eMerCruiser Bravo II X, 2000-2010, serial number M100001 \u0026amp; up\u003c\/li\u003e\n\u003cli\u003eMerCruiser Bravo III, 1988-2010, serial number B664190 \u0026amp; up\u003c\/li\u003e\n\u003cli\u003eMerCruiser Bravo III X, 2000-2010, serial number M100001 \u0026amp; up\u003c\/li\u003e\n\u003cli\u003eMerCruiser Blackhawk, 1994-1995, serial number F186717 \u0026amp; up\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eGLM 87480\u003c\/li\u003e\n\u003cli\u003eMallory 9-74301\u003c\/li\u003e\n\u003cli\u003eMercruiser 26-16709A1\u003c\/li\u003e\n\u003cli\u003e27-16709A2\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat does the Sierra 18-2643 Upper Unit Seal Kit fit?\u003c\/strong\u003e This kit fits MerCruiser Bravo II X (2000-2010, serial number M100001 \u0026amp; up), Bravo III (1988-2010, serial number B664190 \u0026amp; up), Bravo III X (2000-2010, serial number M100001 \u0026amp; up), and Blackhawk (1994-1995, serial number F186717 \u0026amp; up) upper units.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the 18-2643 kit interchangeable with OEM MerCruiser seals?\u003c\/strong\u003e Yes. The Sierra 18-2643 kit is cross-referenced to GLM 87480, Mallory 9-74301, Mercruiser 26-16709A1, and 27-16709A2, and is engineered to meet or exceed the original equipment part it replaces.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the 18-2643 seal kit weigh?\u003c\/strong\u003e The Sierra 18-2643 Upper Unit Seal Kit weighs 0.19 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat color are the seals in the 18-2643 kit?\u003c\/strong\u003e The seals in the Sierra 18-2643 Upper Unit Seal Kit are white.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat shape are the seals in this kit?\u003c\/strong\u003e The seals included in the 18-2643 kit are round.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill the 18-2643 kit fit a MerCruiser Bravo I drive?\u003c\/strong\u003e No fitment for a standard Bravo I is specified for the Sierra 18-2643 kit; it applies to Bravo II X, Bravo III, Bravo III X, and Blackhawk drives within the listed serial-number ranges.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow do I know if my drive is within the serial number range for this kit?\u003c\/strong\u003e Check your MerCruiser drive's serial number tag against the ranges for the Sierra 18-2643 kit: M100001 \u0026amp; up for Bravo II X and Bravo III X, B664190 \u0026amp; up for Bravo III, and F186717 \u0026amp; up for Blackhawk.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is included in the 18-2643 kit?\u003c\/strong\u003e The Sierra 18-2643 Upper Unit Seal Kit includes one complete set of upper gear housing seals for the applicable MerCruiser drives.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs Sierra 18-2643 a genuine Sierra part or aftermarket?\u003c\/strong\u003e The 18-2643 is a genuine Sierra part, manufactured by Sierra as a direct-fit replacement for the original MerCruiser upper unit seals.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the 18-2643 kit come with a warranty?\u003c\/strong\u003e Yes, the Sierra 18-2643 Upper Unit Seal Kit is covered under Sierra's standard limited warranty like all Sierra parts.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the UPC for the Sierra 18-2643 kit?\u003c\/strong\u003e The UPC for the Sierra 18-2643 Upper Unit Seal Kit is 030999875204.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhen would I need to replace the upper unit seals on a MerCruiser Bravo or Blackhawk drive?\u003c\/strong\u003e The Sierra 18-2643 kit is used when servicing the upper gear housing seals, typically to stop gear lubricant leaks or water intrusion in the upper unit of Bravo II X, Bravo III, Bravo III X, or Blackhawk drives.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988108095707,"sku":"SIE-18-2643","price":90.91,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/SIE-18-2643_lg__56288.1558124042.500.750.jpg?v=1785188544","url":"https:\/\/www.goodvibesmarina.com\/products\/upper-unit-seal-kit-18-2643-replaces-mercruiser-26-16709a2-for-bravo-blackhawk-upper-gear-housing","provider":"Good Vibes Marina","version":"1.0","type":"link"}