{"product_id":"mercury-merccruiser-alpha-gear-set-18411a2","title":"Mercury MerCruiser Alpha Upper Gear Set 22\/20T 1.50 Ratio 18411A2","description":"\u003cp\u003eMercury MerCruiser 18411A2 is a genuine OEM \u003cstrong\u003eupper gear set\u003c\/strong\u003e for Alpha-family sterndrives. Current Mercury dealer references identify it as an \u003cstrong\u003eupper gear kit\u003c\/strong\u003e with \u003cstrong\u003e22\/20 teeth\u003c\/strong\u003e and a \u003cstrong\u003e1.50\/1.47 ratio\u003c\/strong\u003e, used in the upper drive gear section rather than as a general lower-unit gear set.\u003c\/p\u003e\n\u003ch2\u003e\u003cstrong\u003eKey Features\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eGenuine Mercury MerCruiser OEM part number \u003cstrong\u003e18411A2\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e22\/20 tooth\u003c\/strong\u003e upper gear set.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e1.50\/1.47 gear ratio\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003eCurrent dealer listing shows \u003cstrong\u003eGTIN 745061123625\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003eCurrent dealer shipping specs are approximately \u003cstrong\u003e4.90 lb\u003c\/strong\u003e, \u003cstrong\u003e7.30 in. x 4.80 in. x 4.60 in.\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003e\u003cstrong\u003eEngine Compatibility\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cp\u003eThe strongest supportable fitment for 18411A2 is \u003cstrong\u003eMerCruiser MC-I, R, MR, Alpha One, and Alpha One Gen II\u003c\/strong\u003e sterndrives with serial coverage shown as \u003cstrong\u003e0K999999 and below\u003c\/strong\u003e, across model years commonly listed from \u003cstrong\u003e1971-1997\u003c\/strong\u003e. This is a \u003cstrong\u003edrive application\u003c\/strong\u003e part, so the sterndrive family matters more than the engine model alone.\u003c\/p\u003e\n\u003ch2\u003e\u003cstrong\u003eSerial Number Fitment Notice\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cp\u003eVerify fitment by exact \u003cstrong\u003edrive model\u003c\/strong\u003e, \u003cstrong\u003eserial number\u003c\/strong\u003e, and the correct \u003cstrong\u003edriveshaft housing \/ drive gears\u003c\/strong\u003e parts diagram before ordering. This gear set spans several older MerCruiser Alpha-family drive applications, so serial-based confirmation is the safest way to match the correct ratio and tooth count.\u003c\/p\u003e\n\u003ch2\u003e\u003cstrong\u003eWhen This Part Needs Replacement\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cp\u003eThis gear set is typically replaced during upper-drive rebuilds when the original gears are worn, chipped, pitted, noisy, or damaged from gearcase failure. Because 18411A2 is the matched upper gear set, it should be selected by the correct ratio and drive family rather than by appearance alone. This is a practical service inference supported by its documented upper-gear-kit application.\u003c\/p\u003e\n\u003ch2\u003e\u003cstrong\u003eInstallation Notes\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cp\u003eInstall 18411A2 only after confirming the correct Alpha-family drive application and ratio requirement. Current parts references place it in the \u003cstrong\u003edriveshaft housing and drive gears\u003c\/strong\u003e section, so it should be matched to the exact upper-drive gear layout during rebuild or reseal work.\u003c\/p\u003e\n\u003ch2\u003e\u003cstrong\u003eAlternate\/Superseded Part Numbers\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cp\u003eCurrent cross-reference sources connect \u003cstrong\u003e59832A2\u003c\/strong\u003e, \u003cstrong\u003e18410A2\u003c\/strong\u003e, and \u003cstrong\u003e59832A4\u003c\/strong\u003e as earlier superseded OEM numbers associated with \u003cstrong\u003e18411A2\u003c\/strong\u003e.\u003c\/p\u003e\n\u003ch2\u003e\u003cstrong\u003eParts Desk Insight\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cp\u003eWith Alpha gear sets, the important match is the \u003cstrong\u003eexact ratio, tooth count, and drive family\u003c\/strong\u003e. A quick serial-number and ratio check usually saves a lot of trouble, especially on older MC-I, MR, Alpha One, and Gen II drives where several gear sets can seem close on paper.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eShipping:\u003c\/strong\u003e Ships same or next day for fast Canada wide shipping. ⚓\u003c\/p\u003e","brand":"MERC","offers":[{"title":"Default Title","offer_id":43563839094820,"sku":"18411A2","price":953.48,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0743\/5799\/7604\/files\/3d6d7f28-1c5c-4abb-8d8c-462ed92d1d81.png?v=1773267108","url":"https:\/\/marisolmarine.com\/products\/mercury-merccruiser-alpha-gear-set-18411a2","provider":"Marisol Marine Company","version":"1.0","type":"link"}