{"product_id":"697-11181-a1-cylinder-head-gasket-for-yamaha-48hp-50hp-55hp-jlm-marine","title":"697-11181-A1 Cylinder Head Gasket for Yamaha 48HP 50HP 55HP | JLM Marine","description":"\u003ch2\u003eCylinder Head Gasket – Fits Yamaha 2-Stroke 48HP, 50HP, 55HP Outboards (1976–2000)\u003c\/h2\u003e\n\n\u003cp\u003eThis cylinder head gasket is engineered for \u003cstrong\u003eYamaha 2-stroke outboard engines rated 48HP, 50HP, and 55HP\u003c\/strong\u003e, spanning model years \u003cstrong\u003e1976 through 2000\u003c\/strong\u003e. It provides a reliable seal between the cylinder head and engine block, essential for maintaining compression and preventing coolant or oil leaks in high-performance marine environments.\u003c\/p\u003e\n\n\u003cp\u003eThis gasket directly replaces OEM part numbers \u003cstrong\u003e697-11181-A1-00\u003c\/strong\u003e, 697-11181-00-00, 697-11181-01-00, 697-11181-A0-00, 697-11181-A2-00, 663-11181-00-00, and Mariner part number 27-81252M, ensuring broad cross-compatibility across multiple Yamaha and Mariner model series.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eDesigned for \u003cstrong\u003e2-cylinder, 2-stroke Yamaha outboards\u003c\/strong\u003e\n\u003c\/li\u003e\n  \u003cli\u003eCritical seal component for maintaining engine compression and preventing leaks\u003c\/li\u003e\n  \u003cli\u003ePrecision-cut to OEM specifications for reliable fitment\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      \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\u003e697-11181-A1-00\u003c\/td\u003e\n      \u003ctd\u003ePrimary OEM reference\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eYamaha\u003c\/td\u003e\n      \u003ctd\u003e697-11181-00-00\u003c\/td\u003e\n      \u003ctd\u003eSuperseded\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eYamaha\u003c\/td\u003e\n      \u003ctd\u003e697-11181-01-00\u003c\/td\u003e\n      \u003ctd\u003eSuperseded\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eYamaha\u003c\/td\u003e\n      \u003ctd\u003e697-11181-A0-00\u003c\/td\u003e\n      \u003ctd\u003eSuperseded\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eYamaha\u003c\/td\u003e\n      \u003ctd\u003e697-11181-A2-00\u003c\/td\u003e\n      \u003ctd\u003eSuperseded\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eYamaha\u003c\/td\u003e\n      \u003ctd\u003e663-11181-00-00\u003c\/td\u003e\n      \u003ctd\u003eSuperseded\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eMariner\u003c\/td\u003e\n      \u003ctd\u003e27-81252M\u003c\/td\u003e\n      \u003ctd\u003eDirect equivalent\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\u003cdiv style=\"overflow-x:auto;\"\u003e\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\u003e48A (S\/N 670-up)\u003c\/td\u003e\n        \u003ctd\u003e48HP\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1976–2000\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003e50C, 50CE, 50CM\u003c\/td\u003e\n        \u003ctd\u003e50HP\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003e55A, 55AM (S\/N 663-up)\u003c\/td\u003e\n        \u003ctd\u003e55HP\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1976–1995\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eE48MLHV\u003c\/td\u003e\n        \u003ctd\u003e48HP\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1997\u003c\/td\u003e\n        \u003ctd\u003eCylinder Crankcase \/ Repair Kit 1\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eE48MLHW\u003c\/td\u003e\n        \u003ctd\u003e48HP\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1998\u003c\/td\u003e\n        \u003ctd\u003eCylinder Crankcase \/ Repair Kit 1\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eE48MLHX\u003c\/td\u003e\n        \u003ctd\u003e48HP\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1999\u003c\/td\u003e\n        \u003ctd\u003eCylinder Crankcase \/ Repair Kit 1\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eYamaha\u003c\/td\u003e\n        \u003ctd\u003eE48MLHY\u003c\/td\u003e\n        \u003ctd\u003e48HP\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e2000\u003c\/td\u003e\n        \u003ctd\u003eCylinder Crankcase \/ Repair Kit 1\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMariner\u003c\/td\u003e\n        \u003ctd\u003e48HP, 55HP\u003c\/td\u003e\n        \u003ctd\u003e48HP \/ 55HP\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e\u003c\/td\u003e\n        \u003ctd\u003e2-Cylinder models\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\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\u003eOEM Part Number\u003c\/td\u003e\n      \u003ctd\u003e697-11181-A1\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eType\u003c\/td\u003e\n      \u003ctd\u003eCylinder Head Gasket\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eApplication\u003c\/td\u003e\n      \u003ctd\u003eYamaha \/ Mariner 2-Stroke Outboards\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eHorsepower Range\u003c\/td\u003e\n      \u003ctd\u003e48HP, 50HP, 55HP\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eCylinder Configuration\u003c\/td\u003e\n      \u003ctd\u003e2-Cylinder\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eMaterial\u003c\/td\u003e\n      \u003ctd\u003eHigh-temperature composite gasket material\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\u003cspan style=\"color:red;\"\u003e\u003cstrong\u003e1 × Cylinder Head Gasket\u003c\/strong\u003e\u003c\/span\u003e (OEM 697-11181-A1)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Guide\u003c\/h2\u003e\n\n\u003col\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDisconnect the battery\u003c\/strong\u003e and ensure the engine is cool before beginning work.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRemove the engine cowling\u003c\/strong\u003e and any components obstructing access to the cylinder head.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDisconnect fuel lines, electrical connectors, and coolant hoses\u003c\/strong\u003e attached to the cylinder head. Label connections for reassembly.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eUnbolt and remove the cylinder head\u003c\/strong\u003e following the manufacturer's torque sequence in reverse.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eClean all mating surfaces\u003c\/strong\u003e on the cylinder head and engine block thoroughly. Remove all traces of old gasket material using a gasket scraper; avoid scratching the aluminum surfaces.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInspect the cylinder head and block\u003c\/strong\u003e for warping, cracks, or damage. Machine or replace components as necessary.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePosition the new gasket\u003c\/strong\u003e on the engine block, aligning all bolt holes and coolant passages precisely.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCarefully lower the cylinder head\u003c\/strong\u003e onto the gasket, ensuring it seats evenly without shifting the gasket.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInstall cylinder head bolts\u003c\/strong\u003e finger-tight, then torque in the correct sequence (typically center-out in a cross pattern) to manufacturer specifications.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eReconnect all coolant hoses, fuel lines, and electrical connections\u003c\/strong\u003e in reverse order of removal.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eReinstall the engine cowling\u003c\/strong\u003e and reconnect the battery.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eStart the engine and check for leaks\u003c\/strong\u003e around the cylinder head. Monitor engine temperature and performance during initial operation.\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 specific Yamaha or Mariner engine?\u003c\/strong\u003e\u003cbr\u003e\nA: Cross-reference your engine's model number and year with the compatibility table above. You can also verify your engine's serial number using the Yamaha Serial Number Guide linked in the compatibility section, or check exploded parts diagrams to confirm the OEM part number matches 697-11181-A1 or its superseded equivalents.\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 loss of compression, rough idling, white smoke from the exhaust (indicating coolant burning), coolant or oil leaks around the cylinder head, overheating, or mixing of oil and coolant. If you notice any of these issues, inspect the gasket promptly.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: Can I reuse the old gasket if it looks undamaged?\u003c\/strong\u003e\u003cbr\u003e\nA: No. Cylinder head gaskets are designed for one-time use and compress permanently during initial installation. Reusing a gasket—even if it appears intact—will likely result in leaks and loss of compression.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: Do I need to use sealant or gasket dressing with this gasket?\u003c\/strong\u003e\u003cbr\u003e\nA: Generally, no additional sealant is required if the mating surfaces are clean and flat. However, consult your engine's service manual; some applications may recommend a light coat of non-hardening gasket dressing on specific areas.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: What torque specifications should I use for the cylinder head bolts?\u003c\/strong\u003e\u003cbr\u003e\nA: Torque specifications vary by engine model. Refer to your Yamaha or Mariner service manual for the exact torque values and tightening sequence. Typical values for these engines range from 18–22 ft-lbs, applied in a cross-pattern from the center outward.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: Is this an OEM gasket or an aftermarket replacement?\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":51981000311097,"sku":"23GT288","price":29.59,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0885\/0433\/6697\/files\/12_e15808de-82fa-4ae3-ba60-1b2e45ae8f34.jpg?v=1772414157","url":"https:\/\/jlmmarine.com\/products\/697-11181-a1-cylinder-head-gasket-for-yamaha-48hp-50hp-55hp-jlm-marine","provider":"JLM Marine Boat Parts Limited","version":"1.0","type":"link"}