{"product_id":"sierra-18-2013-oil-seal-for-mercury-outboard-powerhead-replaces-mercury-marine-26-16977-crankshaft-seal","title":"Sierra Oil Seal 18-2013, Replaces Mercury Marine 26-16977, MerCruiser Alpha I SS and Stern Drive I","description":"\u003cp\u003eThe Sierra 18-2013 is a white oil seal built for MerCruiser stern drive applications, sealing against oil and water intrusion at the drive unit. It is a direct cross-reference to Mercury Marine part 26-16977, making it a straightforward replacement when the original seal fails or wears out during routine drive maintenance.\u003c\/p\u003e\u003cp\u003eThis seal fits the MerCruiser Alpha I SS stern drive (all serial numbers) at the water pump base\/upper location, and the MerCruiser Stern Drive Model I (serial number range 1534570 to 1684187) at the water pump location. Confirm your drive model and serial number range before ordering, since stern drive seals are serial-number specific and installing the wrong seal can lead to leaks or premature failure.\u003c\/p\u003e\u003cp\u003eThe seal is round in shape and finished in white. It ships in compact packaging (2.5 H x 1.3 L x 2.5 W centimeters) and weighs 0.01 pounds, reflecting its small, single-component size. As with any drive seal, replacement is typically done during a water pump service or lower-unit rebuild, and Sierra recommends replacing seals rather than reusing old ones whenever the drive is opened up.\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 18-2013\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eColor:\u003c\/strong\u003e White\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShape:\u003c\/strong\u003e Round\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.01 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePackage Dimensions:\u003c\/strong\u003e 2.5 H x 1.3 L x 2.5 W centimeters\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCountry of Origin:\u003c\/strong\u003e Taiwan\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 030999309594\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM Cross Reference:\u003c\/strong\u003e Mercury Marine 26-16977\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eMerCruiser Alpha I SS Stern Drive (all serial numbers)\u003c\/li\u003e\n\u003cli\u003eMerCruiser Stern Drive Model I, serial numbers 1534570 to 1684187\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\u003cli\u003eMercury Marine 26-16977\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat does the Sierra 18-2013 oil seal fit?\u003c\/strong\u003e The Sierra 18-2013 fits the MerCruiser Alpha I SS stern drive across all serial numbers, and the MerCruiser Stern Drive Model I within serial number range 1534570 to 1684187.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the Sierra 18-2013 the same as Mercury Marine 26-16977?\u003c\/strong\u003e Yes, the Sierra 18-2013 is a direct cross-reference to Mercury Marine part number 26-16977 and can be used in its place.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat color is the 18-2013 oil seal?\u003c\/strong\u003e It is white, and round in shape.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the Sierra 18-2013 oil seal weigh?\u003c\/strong\u003e 0.01 pounds, consistent with its small, single-piece seal design.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWill the 18-2013 seal work on any MerCruiser stern drive?\u003c\/strong\u003e No. It is specific to the MerCruiser Alpha I SS (all serial numbers) and Stern Drive Model I within the 1534570 to 1684187 serial number range; buyers should confirm their drive's serial number before ordering.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhere on the drive does the 18-2013 seal install?\u003c\/strong\u003e On the Alpha I SS it installs at the water pump base\/upper location, and on the Stern Drive Model I it installs at the water pump location.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is included when ordering part 18-2013?\u003c\/strong\u003e One Sierra 18-2013 oil seal is included per unit ordered.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs Sierra 18-2013 a genuine Sierra part or aftermarket?\u003c\/strong\u003e It is a Sierra-branded oil seal manufactured as a replacement part, cross-referenced to Mercury Marine 26-16977.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat are the package dimensions of the 18-2013 seal?\u003c\/strong\u003e The packaged seal measures 2.5 H x 1.3 L x 2.5 W centimeters.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhere is the Sierra 18-2013 oil seal made?\u003c\/strong\u003e It is made in Taiwan.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhen should the 18-2013 oil seal be replaced?\u003c\/strong\u003e This seal is typically replaced during water pump service or a lower-unit rebuild on the applicable MerCruiser stern drive, rather than reusing the old seal.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988090368219,"sku":"SIE-18-2013","price":12.63,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/SIE-18-2013__17433.1780061442.500.750.jpg?v=1785188237","url":"https:\/\/www.goodvibesmarina.com\/products\/sierra-18-2013-oil-seal-for-mercury-outboard-powerhead-replaces-mercury-marine-26-16977-crankshaft-seal","provider":"Good Vibes Marina","version":"1.0","type":"link"}