{"product_id":"yamaha-outboard-powerhead-gasket-set-head-gasket-o-rings-thermostat-exhaust-cover-gaskets-replaces-688-11181-02-00-6h1-w0001-00-00-sierra-18-3805","title":"Sierra Head Gasket 18-3805, Replaces Yamaha 6H1-W0001-00-00, for Yamaha Outboard Engines","description":"\u003cp\u003eThe Sierra 18-3805 is a head gasket engineered as a direct replacement for Yamaha outboard engines. It seals the mating surface between the cylinder head and the powerhead block, maintaining compression and preventing coolant or combustion leaks at this critical joint. As a precision-fit replacement part, it is built to the same sealing tolerances as the original equipment it replaces, making it a straightforward swap when servicing a Yamaha outboard head gasket that has failed or is being replaced as routine maintenance during a top-end rebuild.\u003c\/p\u003e\u003cp\u003eThis head gasket is cataloged under the Yamaha Outboard Head Gaskets category and cross-references directly to Yamaha OEM part numbers, so it can be ordered with confidence as an equivalent to the factory gasket. It is a lightweight, single-component part designed for straightforward removal and installation using standard outboard service procedures and correct torque specifications.\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 18-3805\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Type:\u003c\/strong\u003e Head Gasket\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e Yamaha Outboard Head Gaskets\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.21 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 030999316561\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cp\u003eDesigned for Yamaha outboard engines; specific model, horsepower, and year fitment should be confirmed against the OEM cross-reference numbers below.\u003c\/p\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e6H1-W0001-00-00\u003c\/li\u003e\n\u003cli\u003e6H1-W0001-01-00\u003c\/li\u003e\n\u003cli\u003e6H1-W0001-A0-00\u003c\/li\u003e\n\u003cli\u003e688-11181-02-00\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat does the Sierra 18-3805 head gasket fit?\u003c\/strong\u003e The Sierra 18-3805 is designed for Yamaha outboard engines and is cataloged as a Yamaha Outboard Head Gasket, cross-referencing directly to Yamaha OEM part numbers.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat OEM Yamaha part numbers does 18-3805 replace?\u003c\/strong\u003e Part 18-3805 replaces Yamaha OEM numbers 6H1-W0001-00-00, 6H1-W0001-01-00, 6H1-W0001-A0-00, and 688-11181-02-00.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the Sierra 18-3805 a genuine Yamaha part or aftermarket?\u003c\/strong\u003e The 18-3805 is a Sierra-branded replacement gasket, not an OEM Yamaha part, but it is built to match the OEM Yamaha specifications and cross-references directly to the Yamaha part numbers it replaces.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the 18-3805 head gasket weigh?\u003c\/strong\u003e The Sierra 18-3805 head gasket weighs 0.21 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the UPC for the Sierra 18-3805 head gasket?\u003c\/strong\u003e The UPC for the Sierra 18-3805 head gasket is 030999316561.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhere does the 18-3805 gasket install on the engine?\u003c\/strong\u003e It installs between the cylinder head and the powerhead block on a Yamaha outboard, sealing that joint to maintain compression and prevent coolant or combustion leaks.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I use the 18-3805 gasket for a top-end rebuild?\u003c\/strong\u003e Yes, the Sierra 18-3805 head gasket is suitable for use during a Yamaha outboard top-end rebuild or whenever the head gasket needs replacing due to a failed seal.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat product category does 18-3805 belong to?\u003c\/strong\u003e Sierra part 18-3805 is listed under the Yamaha Outboard Head Gaskets category.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the 18-3805 head gasket come with other gaskets or seals?\u003c\/strong\u003e The 18-3805 is sold as the head gasket itself; it is a single-item part identified by its own Yamaha OEM cross-reference (688-11181-02-00) rather than a multi-piece kit.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow do I confirm the 18-3805 is correct for my Yamaha outboard?\u003c\/strong\u003e Match the OEM number stamped or listed for your Yamaha outboard against the cross-references for 18-3805: 6H1-W0001-00-00, 6H1-W0001-01-00, 6H1-W0001-A0-00, or 688-11181-02-00.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988165898459,"sku":"SIE-18-3805","price":43.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/SIE-18-3805_lg__66508.1558125561.500.750.jpg?v=1785329163","url":"https:\/\/www.goodvibesmarina.com\/products\/yamaha-outboard-powerhead-gasket-set-head-gasket-o-rings-thermostat-exhaust-cover-gaskets-replaces-688-11181-02-00-6h1-w0001-00-00-sierra-18-3805","provider":"Good Vibes Marina","version":"1.0","type":"link"}