Water Pump Impeller Kit – Fits Mercury Marine 2-Cycle Outboards 30-70 HP (Replaces 46-77177A3, Sierra 18-3324)

Water Pump Impeller Kit – Fits Mercury Marine 2-Cycle Outboards 30-70 HP (Replaces 46-77177A3, Sierra 18-3324)

This water pump impeller kit is designed for Mercury/Mariner 2-cycle outboard engines ranging from 30 to 70 horsepower produced between 1977 and 1997. It suits various models including 30 Jet, 35, 40, 45, 50, 60, 65, and 70 HP engines.

The kit is a direct replacement for several OEM components, providing a comprehensive solution for maintaining water pump performance and ensuring reliable cooling functionality.

• Complete water pump repair kit including impeller, housings, gaskets, seals, and hardware
• Compatible with 2-stroke Mercury/Mariner engines listed in specifications
• Installation as a direct replacement for OEM parts to fit precisely

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Compatible Engine Models

Confirm your engine model/year in the table below. For Mercury owners, here’s a guide to help you identify your engine’s serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.

Technical Specifications

Package Contents

• Impeller (89983T)
• Upper Pump Housing (77822A1)
• Water Pump Base/Lower Housing
• Face Plate (32768)
• Upper Water Pump Gasket (19551)
• Lower Water Pump Gasket (19553)
• 2 x Gasket (19552)
• Drain Gasket
• Lower Water Pump Base to Face Plate Gasket
• Upper Face Plate to Body Gasket
• Water Pump Base Gasket
• Drain Plug Gasket
• O-Ring (25-26722)
• 2 x Drain Plug Seal (26-830749)
• 2 x O-Ring (805726)
• Key/Drive Key (8M0032837)
• Rubber (25-20273)
• Shift Bracket Seal (37721001)

Installation Guide

1. Drain the cooling system and remove the lower unit from the outboard engine.
2. Disassemble the water pump housing from the lower unit carefully.
3. Remove the old impeller and all worn gaskets or seals.
4. Clean mating surfaces to remove debris and old gasket material.
5. Install the new impeller ensuring blades face the correct direction for proper water flow.
6. Replace all gaskets, seals, and O-rings included in the kit to ensure a watertight fit.
7. Reassemble the water pump housing and lower unit, tightening fasteners to manufacturer specifications.
8. Reinstall the lower unit onto the engine securely.
9. Refill the cooling system with proper water and check for leaks.
10. Run the engine briefly to confirm water flow and proper cooling operation.
11. Inspect the installation for any signs of leaks or improper fit.
12. Perform routine maintenance checks per service interval recommendations.

Troubleshooting & FAQ

• How do I confirm this fits my engine? Confirm your engine model and year against the compatibility table. Refer to the Mercury Serial Number Guide for serial/model identification and cross-check part numbers using diagrams.
• What are the differences compared to OEM parts? This listing is an aftermarket replacement built to OEM specifications with comparable-grade materials produced in an ISO9002-certified facility.
• How often should I replace the impeller kit? It is recommended to service or replace the water pump impeller kit once per year or every 100 hours of operation.
• What are common signs of water pump failure? Overheating, reduced water flow, and visible leaks or damage to pump components are typical indicators that the impeller or related parts may need replacement.
• OEM vs. Aftermarket? 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.
• How fast do you ship and how much does it cost? We offer fast global shipping typically 5 615 days worldwide 6 and standard shipping is free. Expedited options are available at checkout depending on your location.
• What is your warranty and return policy? 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 & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify 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.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5 615 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.