{"product_id":"water-pump-impeller-kit-fits-mercury-marine-2-cycle-outboards-30-70-hp-replaces-mercury-46-77177a3-sierra-18-3324","title":"Water Pump Impeller Kit – Fits Mercury Marine 2-Cycle Outboards 30-70 HP (Replaces Mercury 46-77177A3, Sierra 18-3324)","description":"\u003csection\u003e\n\u003c!-- 🔧 Table Styles (include only once per page) --\u003e\n\u003cstyle\u003e\n  \/* Outer container allows horizontal scrolling (with iOS momentum) *\/\n  .ss-table-wrap { overflow-x:auto; -webkit-overflow-scrolling:touch; }\n\n  \/* Base table styles *\/\n  table.ss-table { width:100%; border-collapse:collapse; min-width:640px; }\n  table.ss-table th, table.ss-table td {\n    padding:10px 12px; border:1px solid #e5e7eb; text-align:left; vertical-align:top;\n  }\n\n  \/* Key: prevent wrapping, word breaks, and vertical text in headers *\/\n  table.ss-table th {\n    white-space:nowrap;       \/* Do not wrap *\/\n    word-break:normal;        \/* Don’t break words *\/\n    letter-spacing:normal;    \/* Prevent theme styles from stretching letters *\/\n    font-weight:600;\n    background:#f8fafc;\n  }\n\n  \/* Small screen optimization *\/\n  @media (max-width:480px){\n    table.ss-table th, table.ss-table td { padding:8px 10px; font-size:14px; }\n  }\n\u003c\/style\u003e\n\n\u003ch2\u003eProduct Details\u003c\/h2\u003e\n\u003cp\u003eThis \u003cstrong\u003eWater Pump Impeller Kit\u003c\/strong\u003e is a complete assembly designed to restore the cooling system on Mercury and Mariner 2-cycle outboards from 30 to 70 HP (1977–1997). The kit includes the impeller, housing, gaskets, and all necessary hardware for a full replacement, ensuring your engine maintains proper operating temperature.\u003c\/p\u003e\n\u003cp\u003eIt serves as a direct replacement for Mercury parts 46-77177A3\/77177A3 and interchanges with Sierra 18-3324, GLM 12100, and Mallory 9-48312, among others.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eInstalls as a direct replacement for original OEM components.\u003c\/li\u003e\n\u003cli\u003eEngineered with a durable neoprene rubber impeller and a robust PA66 nylon housing.\u003c\/li\u003e\n\u003cli\u003eIncludes all essential gaskets, o-rings, and seals for a complete rebuild.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003ePart Number Matrix\u003c\/h2\u003e\n\u003cp\u003eUse this matrix to confirm equivalent references across OEM and aftermarket.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Part Number Matrix\"\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\u003eMercury\u003c\/td\u003e\n        \u003ctd\u003e46-77177A3\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\u003c\/td\u003e\n        \u003ctd\u003e77177A3\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eSierra\u003c\/td\u003e\n        \u003ctd\u003e18-3324\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eGLM\u003c\/td\u003e\n        \u003ctd\u003e12100\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMallory\u003c\/td\u003e\n        \u003ctd\u003e9-48312\u003c\/td\u003e\n      \u003c\/tr\u003e\n       \u003ctr\u003e\n        \u003ctd\u003eUanofCn\u003c\/td\u003e\n        \u003ctd\u003e18-3324\u003c\/td\u003e\n      \u003c\/tr\u003e\n       \u003ctr\u003e\n        \u003ctd\u003eNorthBoat\u003c\/td\u003e\n        \u003ctd\u003e77177A3\u003c\/td\u003e\n      \u003c\/tr\u003e\n       \u003ctr\u003e\n        \u003ctd\u003eTutor Auto\u003c\/td\u003e\n        \u003ctd\u003e77177A3\u003c\/td\u003e\n      \u003c\/tr\u003e\n       \u003ctr\u003e\n        \u003ctd\u003eSeaSierra\u003c\/td\u003e\n        \u003ctd\u003e77177A3\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eEngine \u0026amp; Model Compatibility\u003c\/h2\u003e\n\u003cp\u003eConfirm your engine model\/year in the table below.\u003c\/p\u003e\n\u003cp\u003eFor Mercury\/Mariner models, verify your engine's serial number falls within the specified range for a guaranteed fit.\u003c\/p\u003e\n\u003cdiv class=\"ss-table-wrap\"\u003e\n  \u003ctable class=\"ss-table\" aria-label=\"Engine \u0026amp; Model Compatibility\"\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\u003eOEM Part No.\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\u003eMercury\u003c\/td\u003e\n        \u003ctd\u003eJet\u003c\/td\u003e\n        \u003ctd\u003e30\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1989–1997\u003c\/td\u003e\n        \u003ctd\u003e46-77177A3\u003c\/td\u003e\n        \u003ctd\u003e4 cylinders, 0C159200 through 0G589999\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n        \u003ctd\u003e[Multiple]\u003c\/td\u003e\n        \u003ctd\u003e35\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1984–1989\u003c\/td\u003e\n        \u003ctd\u003e46-77177A3\u003c\/td\u003e\n        \u003ctd\u003e2 cylinders, 6445653 through 0B110788\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n        \u003ctd\u003e402\u003c\/td\u003e\n        \u003ctd\u003e40\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1978–1979\u003c\/td\u003e\n        \u003ctd\u003e46-77177A3\u003c\/td\u003e\n        \u003ctd\u003e2 cylinders\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n        \u003ctd\u003e[Multiple]\u003c\/td\u003e\n        \u003ctd\u003e40\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1980–1983\u003c\/td\u003e\n        \u003ctd\u003e46-77177A3\u003c\/td\u003e\n        \u003ctd\u003e2 cylinders\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n        \u003ctd\u003e[Multiple]\u003c\/td\u003e\n        \u003ctd\u003e40\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1989 \u0026amp; Up\u003c\/td\u003e\n        \u003ctd\u003e46-77177A3\u003c\/td\u003e\n        \u003ctd\u003e4 cylinders\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n        \u003ctd\u003e[Multiple]\u003c\/td\u003e\n        \u003ctd\u003e45\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1986 \u0026amp; Up\u003c\/td\u003e\n        \u003ctd\u003e46-77177A3\u003c\/td\u003e\n        \u003ctd\u003e4 cylinders\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n        \u003ctd\u003e[Multiple]\u003c\/td\u003e\n        \u003ctd\u003e50\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1978–1985\u003c\/td\u003e\n        \u003ctd\u003e46-77177A3\u003c\/td\u003e\n        \u003ctd\u003e4 cylinders\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n        \u003ctd\u003e[Multiple]\u003c\/td\u003e\n        \u003ctd\u003e50\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1984–1990\u003c\/td\u003e\n        \u003ctd\u003e46-77177A3\u003c\/td\u003e\n        \u003ctd\u003e3 cylinders\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n        \u003ctd\u003e[Multiple]\u003c\/td\u003e\n        \u003ctd\u003e60\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1984–1990\u003c\/td\u003e\n        \u003ctd\u003e46-77177A3\u003c\/td\u003e\n        \u003ctd\u003e3 cylinders\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n        \u003ctd\u003e[Multiple]\u003c\/td\u003e\n        \u003ctd\u003e65\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1976\u003c\/td\u003e\n        \u003ctd\u003e46-77177A3\u003c\/td\u003e\n        \u003ctd\u003e3 cylinders\u003c\/td\u003e\n      \u003c\/tr\u003e\n      \u003ctr\u003e\n        \u003ctd\u003eMercury\/Mariner\u003c\/td\u003e\n        \u003ctd\u003e[Multiple]\u003c\/td\u003e\n        \u003ctd\u003e70\u003c\/td\u003e\n        \u003ctd\u003e2-Stroke\u003c\/td\u003e\n        \u003ctd\u003e1977–1983\u003c\/td\u003e\n        \u003ctd\u003e46-77177A3\u003c\/td\u003e\n        \u003ctd\u003e3 cylinders\u003c\/td\u003e\n      \u003c\/tr\u003e\n    \u003c\/tbody\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eTechnical Specs\u003c\/h2\u003e\n\u003cdl\u003e\n  \u003cdt\u003eProduct Type\u003c\/dt\u003e\n\u003cdd\u003eWater Pump Impeller Repair Kit with Housing\u003c\/dd\u003e\n  \u003cdt\u003eInstallation\u003c\/dt\u003e\n\u003cdd\u003eDirect replacement for OEM components\u003c\/dd\u003e\n  \u003cdt\u003eMaterial\u003c\/dt\u003e\n\u003cdd\u003eNeoprene marine rubber impeller and O-rings, nylon PA66 plastic water pump housing, stainless steel components\u003c\/dd\u003e\n  \u003cdt\u003eHousing Material\u003c\/dt\u003e\n\u003cdd\u003eNylon PA66 plastic\u003c\/dd\u003e\n  \u003cdt\u003eHousing Color\u003c\/dt\u003e\n\u003cdd\u003eBlack\u003c\/dd\u003e\n  \u003cdt\u003eWeight\u003c\/dt\u003e\n\u003cdd\u003e0.31 kg (10.8 oz)\u003c\/dd\u003e\n  \u003cdt\u003eRecommended Service Interval\u003c\/dt\u003e\n\u003cdd\u003eOnce per year or every 100 hours of operation\u003c\/dd\u003e\n  \u003cdt\u003eWarranty\u003c\/dt\u003e\n\u003cdd\u003eVaries by manufacturer (Tutor Auto offers lifetime warranty)\u003c\/dd\u003e\n  \u003cdt\u003eOther Technical Attributes\u003c\/dt\u003e\n\u003cdd\u003ePre-assembled water pump kit contains all necessary components for complete rebuild\u003c\/dd\u003e\n\u003c\/dl\u003e\n\n\u003ch2\u003eWhat’s in the Box\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e1 x Impeller (89983T)\u003c\/li\u003e\n  \u003cli\u003e1 x Upper Pump Housing (77822A1)\u003c\/li\u003e\n  \u003cli\u003e1 x Water Pump Base\/Lower Housing\u003c\/li\u003e\n  \u003cli\u003e1 x Face Plate (32768)\u003c\/li\u003e\n  \u003cli\u003e1 x Upper Water Pump Gasket (19551)\u003c\/li\u003e\n  \u003cli\u003e1 x Lower Water Pump Gasket (19553)\u003c\/li\u003e\n  \u003cli\u003e2 x Gasket (19552)\u003c\/li\u003e\n  \u003cli\u003e1 x Drain Gasket\u003c\/li\u003e\n  \u003cli\u003e1 x Lower Water Pump Base to Face Plate Gasket\u003c\/li\u003e\n  \u003cli\u003e1 x Upper Face Plate to Body Gasket\u003c\/li\u003e\n  \u003cli\u003e1 x Water Pump Base Gasket\u003c\/li\u003e\n  \u003cli\u003e1 x Drain Plug Gasket\u003c\/li\u003e\n  \u003cli\u003e1 x O-Ring (25-26722)\u003c\/li\u003e\n  \u003cli\u003e2 x Drain Plug Seal (26-830749)\u003c\/li\u003e\n  \u003cli\u003e2 x O-Ring (805726)\u003c\/li\u003e\n  \u003cli\u003e1 x Key\/Drive Key (8M0032837)\u003c\/li\u003e\n  \u003cli\u003e1 x Rubber (25-20273)\u003c\/li\u003e\n  \u003cli\u003e1 x Shift Bracket Seal (37721001)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\n\u003col\u003e\n  \u003cli\u003eDisconnect the negative battery terminal.\u003c\/li\u003e\n  \u003cli\u003ePlace a drain pan under the lower unit and remove the gear lube drain\/fill screws to drain the oil.\u003c\/li\u003e\n  \u003cli\u003eRemove the bolts securing the lower unit (gearcase) to the upper leg.\u003c\/li\u003e\n  \u003cli\u003eCarefully separate the lower unit from the driveshaft housing. Note the position of the shift shaft.\u003c\/li\u003e\n  \u003cli\u003eUnbolt and remove the old water pump housing.\u003c\/li\u003e\n  \u003cli\u003eSlide the old impeller, key, wear plate, and gaskets off the driveshaft.\u003c\/li\u003e\n  \u003cli\u003eThoroughly clean all mating surfaces, removing any old gasket material or sealant.\u003c\/li\u003e\n  \u003cli\u003eInstall the new lower gasket, wear plate, and drive key. Slide the new impeller onto the driveshaft, turning it clockwise to seat the vanes correctly.\u003c\/li\u003e\n  \u003cli\u003eInstall the upper gasket and new housing, securing it with the original bolts torqued to manufacturer specs.\u003c\/li\u003e\n  \u003cli\u003eRe-install the lower unit, ensuring the driveshaft, water tube, and shift shaft align properly.\u003c\/li\u003e\n  \u003cli\u003eRefill the lower unit with fresh gear lube from the bottom hole until it flows from the top hole, then replace both screw seals and screws.\u003c\/li\u003e\n  \u003cli\u003eReconnect the battery and test the engine using a water supply (flushing muffs) to confirm cooling system function.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003ch2\u003eTroubleshooting \u0026amp; FAQ\u003c\/h2\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow do I know if this kit fits my engine?\u003c\/summary\u003e\n  \u003cp\u003eThe best way to confirm fitment is to check your engine's model, horsepower, and year against the compatibility table. For Mercury\/Mariner engines, also verify your serial number is within the range listed in the notes column.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat are common signs of a failing water pump impeller?\u003c\/summary\u003e\n  \u003cp\u003eSymptoms include the engine running hotter than normal (overheating), a weak or non-existent water stream from the \"telltale\" outlet, and visible cracks, stiffness, or damage to the old impeller vanes during inspection.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow often should I replace the water pump impeller kit?\u003c\/summary\u003e\n  \u003cp\u003eFor preventative maintenance, we recommend replacing the entire water pump kit, including the housing, once per year or every 100 hours of operation, whichever comes first. This is especially important if you operate in saltwater or debris-heavy water.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhy is my engine overheating after installing the new kit?\u003c\/summary\u003e\n  \u003cp\u003eCommon causes include: incorrect impeller installation (vanes folded the wrong way), a blocked water intake or outlet tube, air leaks from improperly seated gaskets, or a thermostat that is stuck closed. Double-check that all components were installed correctly and that there are no blockages in the cooling system.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eDoes this kit include the upper and lower housing?\u003c\/summary\u003e\n  \u003cp\u003eYes, this is a complete kit that includes the upper pump housing, water pump base (lower housing), face plate, impeller, and all required gaskets and seals for a full rebuild.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat is the difference between an OEM and an aftermarket part?\u003c\/summary\u003e\n  \u003cp\u003eThis listing is an aftermarket replacement (not OEM). It is built to OEM-level specifications with comparable materials, often offering better value. Our parts are manufactured in an ISO 9001 certified facility and are batch-inspected for quality and consistency.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eHow fast is shipping and what does it cost?\u003c\/summary\u003e\n  \u003cp\u003eWe ship worldwide quickly—typical transit time is 5–15 days. Standard shipping is free to most regions, with expedited options available at checkout where applicable.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails\u003e\n  \u003csummary\u003eWhat is the warranty and return policy?\u003c\/summary\u003e\n  \u003cp\u003eThis product is covered by a 1-year warranty against manufacturing defects under normal use. If you encounter any issues, please contact our support team with your order details. Returns are accepted within our standard window for unused items in their original condition. See our policy page or reach out for instructions.\u003c\/p\u003e\n\u003c\/details\u003e\n\n\u003ch2\u003eSafety \u0026amp; Important Info\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eVerify images\/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.\u003c\/li\u003e\n  \u003cli\u003eThis is an aftermarket replacement, not an OEM component.\u003c\/li\u003e\n  \u003cli\u003eProfessional installation is recommended for safety and performance.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eAbout Sea Sierra\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePro-Grade Standards\u003c\/strong\u003e — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFast Global Fulfillment\u003c\/strong\u003e — Free standard delivery to most regions in 5–15 days.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer-Direct Value\u003c\/strong\u003e — Fair pricing without compromising on materials or QC.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003c\/section\u003e","brand":"SeaSierra","offers":[{"title":"Default Title","offer_id":50723964846395,"sku":"LQ-PF3G-5LLB","price":29.89,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0826\/8673\/8747\/files\/LQ-PF3G-5LLB.png?v=1763038561","url":"https:\/\/seasierra.com\/products\/water-pump-impeller-kit-fits-mercury-marine-2-cycle-outboards-30-70-hp-replaces-mercury-46-77177a3-sierra-18-3324","provider":"SeaSierra","version":"1.0","type":"link"}