{"product_id":"brass-spline-washer-for-mercury-prop-hardware-replaces-12-31211a2-sierra-18-3714","title":"Sierra Brass Castle Washer 18-3714, Replaces Mercury 12-31211A2, Fits 135-275 HP V6 2-Cycle Outboards","description":"\u003cp\u003eThe Sierra 18-3714 is a brass castle washer used on outboard propeller hardware. A castle washer is designed to work with a cotter pin to lock the propeller nut securely in place, preventing the nut from backing off during operation. Built from brass, it resists corrosion in the marine environment better than uncoated steel hardware, making it a reliable choice for maintaining a secure and dependable propeller assembly.\u003c\/p\u003e\u003cp\u003eThis washer is intended for outboards rated 135-275 HP with V6 2 cycle engines. It directly replaces several Mercury Marine OEM part numbers, so it can be used as a drop-in service or replacement part when rebuilding or servicing the propeller hub assembly. Keeping this hardware in good condition is a simple, low-cost way to avoid a lost or loosening propeller nut.\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 18-3714\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Type:\u003c\/strong\u003e Brass Castle Washer\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Brass\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFitment:\u003c\/strong\u003e 135-275 HP (V6 2 cycle)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.28 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 030999755902\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM Cross Reference:\u003c\/strong\u003e 12-31211A2, 12-31211, 12-31211A3, 12-31211Q03\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cul\u003e\u003cli\u003e135-275 HP (V6 2 cycle) outboards\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e12-31211A2\u003c\/li\u003e\n\u003cli\u003e12-31211\u003c\/li\u003e\n\u003cli\u003e12-31211A3\u003c\/li\u003e\n\u003cli\u003e12-31211Q03\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat is the Sierra 18-3714 castle washer used for?\u003c\/strong\u003e The Sierra 18-3714 is a brass castle washer used on outboard propeller hardware; it seats against the propeller nut and is paired with a cotter pin to keep the nut from loosening during operation.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat outboards does the 18-3714 castle washer fit?\u003c\/strong\u003e This washer is fitted for outboards rated 135-275 HP with V6 2 cycle engines.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat OEM part numbers does the 18-3714 washer replace?\u003c\/strong\u003e It replaces Mercury OEM numbers 12-31211A2, 12-31211, 12-31211A3, and 12-31211Q03.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the 18-3714 washer made of brass or steel?\u003c\/strong\u003e It is made of brass, chosen for its corrosion resistance in marine environments compared to uncoated steel hardware.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the Sierra 18-3714 castle washer weigh?\u003c\/strong\u003e The Sierra 18-3714 brass castle washer weighs 0.28 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDo I need a cotter pin with the 18-3714 castle washer?\u003c\/strong\u003e Yes, a castle washer like the 18-3714 is designed to be used with a cotter pin passed through the slots to lock the propeller nut in place.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the Sierra 18-3714 a genuine Sierra part or aftermarket?\u003c\/strong\u003e The 18-3714 is a Sierra-branded replacement part manufactured to replace the listed Mercury OEM castle washers.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the UPC for the Sierra 18-3714 castle washer?\u003c\/strong\u003e The UPC for the Sierra 18-3714 brass castle washer is 030999755902.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan the 18-3714 washer be used on any outboard propeller?\u003c\/strong\u003e The 18-3714 castle washer is intended for 135-275 HP V6 2 cycle outboards and the specific Mercury hub hardware it cross-references; it should be matched to that fitment before ordering.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the 18-3714 come as a single washer or multiple?\u003c\/strong\u003e The Sierra 18-3714 brass castle washer is supplied as an individual replacement washer.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988162326747,"sku":"SIE-18-3714","price":9.3,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/SIE-18-3714_lg__34480.1558126527.500.750.jpg?v=1785188275","url":"https:\/\/www.goodvibesmarina.com\/products\/brass-spline-washer-for-mercury-prop-hardware-replaces-12-31211a2-sierra-18-3714","provider":"Good Vibes Marina","version":"1.0","type":"link"}