{"product_id":"merc-477","title":"Mercury Water Pump Screw 74191","description":"\u003cp\u003eMercury MerCruiser 74191 is a genuine OEM \u003cstrong\u003escrew\u003c\/strong\u003e sized \u003cstrong\u003e.312-18 x 3.250\u003c\/strong\u003e. Current Mercury dealer references list it as \u003cstrong\u003e10-74191 Screw (.312-18 x 3.250)\u003c\/strong\u003e and show it superseded to current replacement part number \u003cstrong\u003e8M0204669\u003c\/strong\u003e. It is commonly used in MerCruiser sea water pump service, including pump body \/ impeller kit applications where this screw secures the pump assembly.\u003c\/p\u003e\n\u003ch2\u003e\u003cstrong\u003eKey Features\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eGenuine Mercury Marine OEM part number \u003cstrong\u003e74191 \/ 10-74191\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003eCurrent replacement part number is \u003cstrong\u003e8M0204669\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003eSize listed by Mercury as \u003cstrong\u003e.312-18 x 3.250\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003eCurrent dealer listing shows \u003cstrong\u003eGTIN \/ UPC 745061175501\u003c\/strong\u003e.\u003c\/li\u003e\n\u003cli\u003eCurrent dealer shipping specs are approximately \u003cstrong\u003e0.06 lb\u003c\/strong\u003e, \u003cstrong\u003e3.50 in. x 0.50 in. x 0.50 in.\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli\u003eCurrent Mercury kit references show this screw used in \u003cstrong\u003e46-807151A14 water pump body and impeller kit\u003c\/strong\u003e contents.\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 74191 is \u003cstrong\u003eMerCruiser sea water pump service\u003c\/strong\u003e, especially applications using the plastic one-piece body sea water pump found across Alpha engines with closed cooling and internal pump, Bravo, Ski, Inboard, 330 B-W TR\/TRS, and high-performance engines without a solid plate front mount, as shown in the Mercury water pump body and impeller kit reference.\u003c\/p\u003e\n\u003ch2\u003e\u003cstrong\u003eSerial Number Fitment Notice\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cp\u003eVerify fitment by exact \u003cstrong\u003eengine or drive serial number\u003c\/strong\u003e and the correct \u003cstrong\u003esea water pump \/ pump body\u003c\/strong\u003e parts diagram before ordering. This screw is a specific size and application hardware item, so serial-based confirmation is the safest way to match the correct water pump fastener and current replacement number.\u003c\/p\u003e\n\u003ch2\u003e\u003cstrong\u003eWhen This Part Needs Replacement\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cp\u003eReplace this screw when the original is corroded, rounded, seized, stretched, missing, or removed during sea water pump service and no longer suitable for reuse. Since this screw is part of the pump-body fastening hardware, correct thread, length, and condition matter during impeller or pump-body reassembly.\u003c\/p\u003e\n\u003ch2\u003e\u003cstrong\u003eInstallation Notes\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cp\u003eInstall 74191 or current replacement \u003cstrong\u003e8M0204669\u003c\/strong\u003e only after confirming the correct MerCruiser sea water pump layout. Current Mercury kit contents list this screw with the water pump assembly, O-ring, impeller, quad ring, wear plate, and related washers, so it should be matched to the exact pump stack during service.\u003c\/p\u003e\n\u003ch2\u003e\u003cstrong\u003eAlternate\/Superseded Part Numbers\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cp\u003eCurrent Mercury references show \u003cstrong\u003e8M0204669\u003c\/strong\u003e as the active replacement for \u003cstrong\u003e74191 \/ 10-74191\u003c\/strong\u003e.\u003c\/p\u003e\n\u003ch2\u003e\u003cstrong\u003eParts Desk Insight\u003c\/strong\u003e\u003c\/h2\u003e\n\u003cp\u003eWith sea water pump hardware, the important match is the \u003cstrong\u003ethread size, length, and pump-body layout\u003c\/strong\u003e. A quick parts-diagram check helps avoid mixing this \u003cstrong\u003e3-1\/4 inch\u003c\/strong\u003e screw with shorter pump screws used in the same service area.\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":43563870486564,"sku":"74191","price":6.36,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0743\/5799\/7604\/files\/264ec1d7-f2bb-4156-98e4-a73a756e7b41.png?v=1777070802","url":"https:\/\/marisolmarine.com\/products\/merc-477","provider":"Marisol Marine Company","version":"1.0","type":"link"}