{"product_id":"sierra-18-3751-spanner-nut-for-mercruiser-alpha-one-gen-ii-bravo-sterndrives-replaces-mercury-14-79447","title":"Sierra Spanner Nut 18-3751, Replaces Mercury Marine 79448, For V-6 Reverse Clutch","description":"\u003cp\u003eThe Sierra 18-3751 Spanner Nut is a stainless steel locknut engineered for V-6 stern drive reverse clutch assemblies. It is machined to precisely thread onto the driveshaft and hold the reverse clutch components in correct alignment and preload during operation. As a direct replacement for Mercury Marine part 79448, it restores original fit and function when the factory nut is worn, corroded, or damaged during a clutch or bearing service.\u003c\/p\u003e\u003cp\u003eConstructed from stainless steel for corrosion resistance in the marine environment, this spanner nut is a small but critical component in the reverse clutch stack, and using the correct part number ensures proper torque retention and clutch engagement. It is sold individually and is priced per package.\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 18-3751\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Name:\u003c\/strong\u003e Spanner Nut\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Stainless steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.23 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 030999316509\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication:\u003c\/strong\u003e V-6 reverse clutch\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM Cross Reference:\u003c\/strong\u003e Mercury Marine 79448\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cul\u003e\u003cli\u003eV-6\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\u003cli\u003e79448\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat does the Sierra 18-3751 Spanner Nut replace?\u003c\/strong\u003e The Sierra 18-3751 Spanner Nut is a direct replacement for Mercury Marine part number 79448.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat engine application is the 18-3751 spanner nut designed for?\u003c\/strong\u003e Sierra 18-3751 is designed for V-6 reverse clutch applications.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat material is the 18-3751 spanner nut made from?\u003c\/strong\u003e It is made from stainless steel, which resists corrosion in marine environments.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the Sierra 18-3751 Spanner Nut weigh?\u003c\/strong\u003e This spanner nut weighs 0.23 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs Sierra 18-3751 a genuine Sierra part or an aftermarket copy?\u003c\/strong\u003e 18-3751 is a genuine Sierra International part, sold under Sierra's own part number as a replacement for Mercury Marine 79448.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the UPC for the Sierra 18-3751 Spanner Nut?\u003c\/strong\u003e The UPC for the Sierra 18-3751 Spanner Nut is 030999316509.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow is the Sierra 18-3751 Spanner Nut sold?\u003c\/strong\u003e The 18-3751 Spanner Nut is priced and sold per package as an individual locknut.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat role does the spanner nut play in a reverse clutch assembly?\u003c\/strong\u003e In the V-6 reverse clutch assembly, the 18-3751 spanner nut threads onto the driveshaft to secure and preload the reverse clutch components.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill the Mercury Marine 79448 nut work in place of Sierra 18-3751?\u003c\/strong\u003e Yes, Mercury Marine 79448 and Sierra 18-3751 are the same replacement part, so either part number will fit the same V-6 reverse clutch application.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the Sierra 18-3751 come with washers or other clutch hardware?\u003c\/strong\u003e No, 18-3751 is the spanner nut only; it does not include tab washers or other reverse clutch hardware.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988165243099,"sku":"SIE-18-3751","price":24.87,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/18-3751__38182.1737899487.500.750.jpg?v=1785187981","url":"https:\/\/www.goodvibesmarina.com\/products\/sierra-18-3751-spanner-nut-for-mercruiser-alpha-one-gen-ii-bravo-sterndrives-replaces-mercury-14-79447","provider":"Good Vibes Marina","version":"1.0","type":"link"}