{"product_id":"sierra-18-7158-o-ring-for-mercury-mariner-outboards-replaces-oem-310967-310585","title":"Sierra O-Ring 18-7158 for Mercruiser Bravo I\/II Stern Drives (S\/N B664190 and Up)","description":"\u003cp\u003eThe Sierra O-Ring 18-7158 is a replacement drive seal designed for Bravo I and Bravo II stern drives with beginning serial number B664190 and up. This O-ring is used as part of the stern drive gearcase seal set and is installed one per drive during gearcase service or reassembly to maintain a proper seal at the drive housing.\u003c\/p\u003e\u003cp\u003eUsing the correct O-ring during stern drive service helps prevent water intrusion and lubricant loss at the sealing surface. Because stern drive seals are matched to specific serial number ranges, confirming your drive's serial number against the range listed below ensures you install the correct part for your unit.\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 18-7158\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Type:\u003c\/strong\u003e O-Ring\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e Mercury Outboard O-Rings \u0026amp; Seals\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.02 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eQuantity per Stern Drive:\u003c\/strong\u003e 1\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 808282259693\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cul\u003e\u003cli\u003eBravo I\/II Stern Drive, beginning serial number B664190 and up\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat is the Sierra 18-7158 O-Ring used for?\u003c\/strong\u003e The Sierra 18-7158 is a replacement O-ring used in the gearcase seal set on Bravo I and Bravo II stern drives, installed one per drive.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhich stern drives fit the 18-7158 O-ring?\u003c\/strong\u003e This O-ring fits Bravo I\/II stern drives with a beginning serial number of B664190 and up.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow many 18-7158 O-rings does one stern drive need?\u003c\/strong\u003e One Sierra 18-7158 O-ring is required per stern drive.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow do I know if my stern drive uses the 18-7158 O-ring instead of a different Sierra seal?\u003c\/strong\u003e Check your Bravo I\/II stern drive's serial number; the 18-7158 O-ring applies to units with beginning serial number B664190 and up, so drives outside that range may require a different Sierra part.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the Sierra 18-7158 O-ring weigh?\u003c\/strong\u003e The Sierra 18-7158 O-ring weighs 0.02 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the Sierra 18-7158 a genuine Sierra part or an aftermarket equivalent?\u003c\/strong\u003e The 18-7158 is a Sierra-branded replacement part sold under Sierra's own part number for Bravo I\/II stern drive service.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhere on the stern drive does the 18-7158 O-ring install?\u003c\/strong\u003e It is installed as part of the gearcase seal assembly on Bravo I\/II stern drives during service or reassembly.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the Sierra 18-7158 O-ring sold individually or in a kit?\u003c\/strong\u003e The Sierra 18-7158 is sold as a single O-ring, with one required per Bravo I\/II stern drive.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the 18-7158 O-ring fit Bravo III stern drives?\u003c\/strong\u003e No, the Sierra 18-7158 O-ring is designated for Bravo I\/II stern drives with serial number B664190 and up; other Bravo models use different Sierra seal part numbers.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988364800219,"sku":"SIE-18-7158","price":0.21,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/18-7158__37591.1722496468.500.750.jpg?v=1785329172","url":"https:\/\/www.goodvibesmarina.com\/products\/sierra-18-7158-o-ring-for-mercury-mariner-outboards-replaces-oem-310967-310585","provider":"Good Vibes Marina","version":"1.0","type":"link"}