{"product_id":"6g8-11181-a1-cylinder-head-gasket-for-yamaha-f8-f9-9-jlm-marine","title":"6G8-11181-A1 Cylinder Head Gasket for Yamaha F8 F9.9 | JLM Marine","description":"\u003ch2\u003eCylinder Head Gasket for Yamaha F8 F9.9 Outboard – OEM 6G8-11181-A1\u003c\/h2\u003e\n\n\u003cp\u003eThis cylinder head gasket is engineered to fit \u003cstrong\u003eYamaha F8 and F9.9 four-stroke outboard engines\u003c\/strong\u003e manufactured between 1985 and 1996, specifically models with \u003cstrong\u003e6G8 and 6G9 serial numbers\u003c\/strong\u003e. It provides a critical seal between the cylinder head and engine block, ensuring proper compression and preventing coolant or oil leaks.\u003c\/p\u003e\n\n\u003cp\u003eThis gasket directly replaces Yamaha OEM part number \u003cstrong\u003e6G8-11181-A1\u003c\/strong\u003e, offering a precise fit for reliable engine performance and longevity.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eDesigned for Yamaha 4-stroke 8 HP and 9.9 HP outboards\u003c\/li\u003e\n  \u003cli\u003ePrecision-cut for exact OEM specifications\u003c\/li\u003e\n  \u003cli\u003eEssential component for engine rebuilds and head service\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Number Cross-Reference\u003c\/h2\u003e\n\n\u003cp\u003eUse this table to confirm equivalent part numbers across OEM and aftermarket brands.\u003c\/p\u003e\n\n\u003ctable border=\"1\" cellpadding=\"8\" cellspacing=\"0\"\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n      \u003cth\u003eBrand\u003c\/th\u003e\n      \u003cth\u003ePart Number\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eYamaha\u003c\/td\u003e\n      \u003ctd\u003e6G8-11181-A1\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eCompatible Engine Models\u003c\/h2\u003e\n\n\u003cp\u003eConfirm your engine model\/year in the table below. For Yamaha owners, here's a guide to help you identify your engine's serial\/model: \u003ca href=\"https:\/\/jlmmarine.com\/blogs\/serial-number-guide\/yamaha-outboard-serial-number-guide-2025\" rel=\"nofollow noopener\" target=\"_blank\"\u003eYamaha Serial Number Guide\u003c\/a\u003e. You can also review exploded diagrams to verify part numbers: \u003ca href=\"https:\/\/jlmmarine.com\/blogs\/serial-number-guide\/yamaha-outboard-parts-diagrams-catalog\" rel=\"nofollow noopener\" target=\"_blank\"\u003eYamaha Parts Diagrams \u0026amp; Catalog\u003c\/a\u003e.\u003c\/p\u003e\n\n\u003ctable border=\"1\" cellpadding=\"8\" cellspacing=\"0\"\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n      \u003cth\u003eBrand\u003c\/th\u003e\n      \u003cth\u003eModel\u003c\/th\u003e\n      \u003cth\u003eRated HP\u003c\/th\u003e\n      \u003cth\u003eStroke\u003c\/th\u003e\n      \u003cth\u003eYears\u003c\/th\u003e\n      \u003cth\u003eNotes\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eYamaha\u003c\/td\u003e\n      \u003ctd\u003eF8\u003c\/td\u003e\n      \u003ctd\u003e8 HP\u003c\/td\u003e\n      \u003ctd\u003e4-Stroke\u003c\/td\u003e\n      \u003ctd\u003e1985-1996\u003c\/td\u003e\n      \u003ctd\u003eModels with 6G8, 6G9 serial number\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eYamaha\u003c\/td\u003e\n      \u003ctd\u003eF9.9\u003c\/td\u003e\n      \u003ctd\u003e9.9 HP\u003c\/td\u003e\n      \u003ctd\u003e4-Stroke\u003c\/td\u003e\n      \u003ctd\u003e1985-1996\u003c\/td\u003e\n      \u003ctd\u003eModels with 6G8, 6G9 serial number\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\n\u003ctable border=\"1\" cellpadding=\"8\" cellspacing=\"0\"\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n      \u003cth\u003eSpecification\u003c\/th\u003e\n      \u003cth\u003eValue\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd\u003ePart Type\u003c\/td\u003e\n      \u003ctd\u003eCylinder Head Gasket\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eOEM Part Number\u003c\/td\u003e\n      \u003ctd\u003e6G8-11181-A1\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eCompatible Brand\u003c\/td\u003e\n      \u003ctd\u003eYamaha\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eEngine Type\u003c\/td\u003e\n      \u003ctd\u003e4-Stroke Outboard\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eHorsepower Range\u003c\/td\u003e\n      \u003ctd\u003e8 HP - 9.9 HP\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eApplicable Years\u003c\/td\u003e\n      \u003ctd\u003e1985-1996\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eSerial Number Compatibility\u003c\/td\u003e\n      \u003ctd\u003e6G8, 6G9\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003ePackage Contents\u003c\/h2\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003e1 × Cylinder Head Gasket\u003c\/strong\u003e (6G8-11181-A1)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Guide\u003c\/h2\u003e\n\n\u003col\u003e\n  \u003cli\u003eDisconnect the battery and allow the engine to cool completely before starting any work.\u003c\/li\u003e\n  \u003cli\u003eRemove the engine cowling and disconnect fuel lines, electrical connections, and coolant hoses as necessary to access the cylinder head.\u003c\/li\u003e\n  \u003cli\u003eUnbolt and carefully remove the cylinder head from the engine block, taking care not to damage the mating surfaces.\u003c\/li\u003e\n  \u003cli\u003eThoroughly clean both the cylinder head and engine block mating surfaces, removing all traces of old gasket material, oil, and debris. Use a gasket scraper and solvent as needed.\u003c\/li\u003e\n  \u003cli\u003eInspect both surfaces for warping, cracks, or damage; resurface or replace components if necessary.\u003c\/li\u003e\n  \u003cli\u003ePosition the new cylinder head gasket onto the engine block, aligning all bolt holes and coolant\/oil passages precisely.\u003c\/li\u003e\n  \u003cli\u003eCarefully place the cylinder head back onto the engine block, ensuring the gasket remains properly aligned.\u003c\/li\u003e\n  \u003cli\u003eInstall cylinder head bolts hand-tight in a crisscross pattern, starting from the center and working outward.\u003c\/li\u003e\n  \u003cli\u003eTorque the head bolts to the manufacturer's specified torque settings in the proper sequence (refer to your service manual).\u003c\/li\u003e\n  \u003cli\u003eReconnect all coolant hoses, fuel lines, and electrical connections that were removed earlier.\u003c\/li\u003e\n  \u003cli\u003eRefill coolant and check all fluid levels before reinstalling the cowling.\u003c\/li\u003e\n  \u003cli\u003eStart the engine and inspect for leaks around the cylinder head gasket area; re-torque head bolts after initial operation if recommended by the service manual.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: How do I confirm this gasket fits my Yamaha outboard?\u003c\/strong\u003e\u003cbr\u003e\nA: Verify that your engine is an F8 or F9.9 four-stroke model manufactured between 1985 and 1996 with a 6G8 or 6G9 serial number. Cross-check your existing gasket or OEM part number against 6G8-11181-A1 to ensure compatibility.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: What are the signs that my cylinder head gasket needs replacement?\u003c\/strong\u003e\u003cbr\u003e\nA: Common symptoms include coolant or oil leaks around the cylinder head, overheating, white smoke from the exhaust, loss of compression, rough idling, or mixing of oil and coolant. If you observe any of these issues, inspect and replace the gasket as needed.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: Do I need to replace other components when changing the cylinder head gasket?\u003c\/strong\u003e\u003cbr\u003e\nA: While replacing the gasket, it's a good opportunity to inspect the cylinder head for warping or cracks, check head bolts for stretching, and replace valve cover gaskets or seals if they show wear. Always follow your service manual's recommendations.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: Can I reuse the old cylinder head gasket?\u003c\/strong\u003e\u003cbr\u003e\nA: No, cylinder head gaskets are designed for single use only. Once compressed and heated during engine operation, they lose their sealing properties and cannot be reused. Always install a new gasket when removing the cylinder head.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: What is the difference between OEM and aftermarket gaskets?\u003c\/strong\u003e\u003cbr\u003e\nA: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: How fast do you ship and how much does it cost?\u003c\/strong\u003e\u003cbr\u003e\nA: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: What is your warranty and return policy?\u003c\/strong\u003e\u003cbr\u003e\nA: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused \u0026amp; in original condition); please see our policy page or reach out for instructions.\u003c\/p\u003e\n\n\u003ch2\u003eImportant Notes\u003c\/h2\u003e\n\n\u003cul\u003e\n  \u003cli\u003eVerify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.\u003c\/li\u003e\n  \u003cli\u003eThis product is an aftermarket replacement part and is not an OEM component.\u003c\/li\u003e\n  \u003cli\u003eProfessional installation is recommended to ensure safety and optimal performance.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhy Choose JLM MARINE?\u003c\/h2\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eQuality Assured:\u003c\/strong\u003e As a trusted manufacturer for over 20 years, we supply top marine brands globally.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFast Global Shipping:\u003c\/strong\u003e Free delivery worldwide in 5–15 days.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDirect from Manufacturer:\u003c\/strong\u003e Competitive pricing without compromising quality.\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"JLM Marine","offers":[{"title":"Default Title","offer_id":51981000343865,"sku":"23GT289","price":19.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0885\/0433\/6697\/files\/12_6daad420-012e-40ba-833f-8f8712f02799.jpg?v=1772414159","url":"https:\/\/jlmmarine.com\/products\/6g8-11181-a1-cylinder-head-gasket-for-yamaha-f8-f9-9-jlm-marine","provider":"JLM Marine Boat Parts Limited","version":"1.0","type":"link"}