{"product_id":"sierra-18-3802-powerhead-mounting-twin-gasket-for-johnson-evinrude-outboards-replaces-omc-326468-351018","title":"Sierra 18-3802 Head Gasket for Johnson\/Evinrude 40 HP and 45 HP Outboard Motors","description":"\u003cp\u003eThe Sierra 18-3802 is a marine head gasket built for Johnson\/Evinrude outboard motors, sold as a direct-fit replacement for the original equipment gasket on the power head. It seals the joint between the cylinder head and the engine block, maintaining proper compression and preventing coolant or combustion leaks that can lead to overheating or power loss. The gasket is engineered to meet or exceed original equipment quality, making it a reliable choice for a power head rebuild or a routine gasket replacement.\u003c\/p\u003e\u003cp\u003eThe 18-3802 is finished in white and is fit-specific to the outboard models it covers, so buyers should confirm their engine's horsepower rating and model year before ordering. It is designed as a drop-in match for the factory gasket location, requiring no modification to install. Because head gaskets are wear items exposed to heat cycling and combustion pressure, replacing this gasket during a top-end service helps restore proper sealing and compression on applicable Johnson\/Evinrude power heads.\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 18-3802\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCategory:\u003c\/strong\u003e Evinrude Outboard Power Head Gasket\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor:\u003c\/strong\u003e White\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.13 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 030999316530\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eJohnson\/Evinrude 40 HP outboard, 1984-97\u003c\/li\u003e\n\u003cli\u003eJohnson\/Evinrude 40 HP Commercial outboard, 1994-97\u003c\/li\u003e\n\u003cli\u003eJohnson\/Evinrude 45 HP Commercial outboard, 1985-97\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e335359\u003c\/li\u003e\n\u003cli\u003e327795\u003c\/li\u003e\n\u003cli\u003e320658\u003c\/li\u003e\n\u003cli\u003eGLM 34250\u003c\/li\u003e\n\u003cli\u003eMallory 9-63833\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat is the Sierra 18-3802 head gasket used for?\u003c\/strong\u003e The Sierra 18-3802 seals the joint between the cylinder head and the power head block on Johnson\/Evinrude outboard motors, maintaining compression and preventing coolant or combustion leaks.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhich Johnson\/Evinrude outboards fit the 18-3802 head gasket?\u003c\/strong\u003e The 18-3802 fits the Johnson\/Evinrude 40 HP outboard (1984-97), the 40 HP Commercial outboard (1994-97), and the 45 HP Commercial outboard (1985-97).\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the 18-3802 gasket a genuine OEM part or aftermarket?\u003c\/strong\u003e The 18-3802 is a Sierra-brand replacement gasket manufactured to meet or exceed original equipment quality; it is not an OEM Johnson\/Evinrude branded part but is built as a direct equivalent.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat OEM part numbers does the Sierra 18-3802 replace?\u003c\/strong\u003e The Sierra 18-3802 head gasket cross-references to OEM and interchange numbers 335359, 327795, and 320658, as well as GLM 34250 and Mallory 9-63833.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the 18-3802 head gasket weigh?\u003c\/strong\u003e The Sierra 18-3802 head gasket weighs 0.13 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat color is the 18-3802 head gasket?\u003c\/strong\u003e This head gasket is white.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill the 18-3802 fit a Johnson\/Evinrude engine outside the listed HP and years?\u003c\/strong\u003e The 18-3802 is fit-specific to the Johnson\/Evinrude 40 HP (1984-97), 40 HP Commercial (1994-97), and 45 HP Commercial (1985-97) outboards; buyers should check their engine's HP and model year against these listings before ordering.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow do I know if I need to replace my head gasket?\u003c\/strong\u003e Signs that a power head gasket like the 18-3802 needs replacement include coolant leaks at the cylinder head joint, loss of compression, or overheating on the applicable Johnson\/Evinrude outboard.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs installation of the 18-3802 gasket straightforward?\u003c\/strong\u003e The 18-3802 is a direct-fit replacement gasket for the factory location on covered Johnson\/Evinrude power heads, requiring no modification to install during a head or top-end service.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the UPC for the Sierra 18-3802 head gasket?\u003c\/strong\u003e The UPC for the Sierra 18-3802 head gasket is 030999316530.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988165963995,"sku":"SIE-18-3802","price":30.41,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/SIE-18-3802_lg__20816.1558125375.500.750.jpg?v=1785187990","url":"https:\/\/www.goodvibesmarina.com\/products\/sierra-18-3802-powerhead-mounting-twin-gasket-for-johnson-evinrude-outboards-replaces-omc-326468-351018","provider":"Good Vibes Marina","version":"1.0","type":"link"}