Water Pump Impeller Kit – Fits Mercury Marine 30-70 HP Outboards (Replaces 46-60366A1, 46-32767A1)

Water Pump Impeller Kit – Fits Mercury Marine 30-70 HP Outboards

This water pump impeller service kit is designed for a wide range of Mercury Marine outboard motors from 30 to 70 HP, covering various 2-stroke and 4-stroke models manufactured from the 1960s through the 1980s. It provides a direct replacement solution for maintaining your engine's cooling system.

This kit directly replaces Mercury part numbers 46-60366A1, 46-32767A1, 46-60366Q1, and 46-60366T1, as well as several aftermarket equivalents.

• Core Components: Includes a durable Neoprene marine rubber impeller and a Nylon PA66 plastic water pump housing.
• Installation: Mounts directly to the engine's lower unit.
• Engine Compatibility: Fits various Mercury outboards up to a maximum of 70 HP.

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

• 1 x Upper Pump Housing (46-77822A1)
• 1 x Impeller (47-89983)
• 2 x Drain Gasket (12-20260/12-19183)
• 1 x Lower Water Pump Base to Face Plate Gasket (27-32769/27-19553)
• 1 x Upper Face Plate to Pump Body Gasket (27-32770)
• 1 x Water Pump Base Gasket (27-32771/27-19551)
• 1 x Water Pump Base Gasket (27-77417/27-19552)
• 1 x Rubber Washer (12-49221-1)
• 1 x Plate (54705)
• 1 x O-Ring (25-26855)
• 1 x O-Ring (25-45711)
• 1 x O-Ring (25-26722)

Installation Guide

1. Safety First: Disconnect the battery and ensure the engine is turned off and cool to the touch.
2. Access the Lower Unit: Place the outboard motor in a secure position and drain the gearcase oil from the lower unit.
3. Remove Lower Unit: Unbolt and carefully detach the lower unit (gearcase) from the upper engine housing.
4. Disassemble Pump: Locate the water pump assembly on top of the lower unit. Remove the bolts securing the water pump housing.
5. Remove Old Components: Take out the old housing, impeller, gaskets, and wear plate. Note the orientation of the impeller vanes.
6. Clean Surfaces: Thoroughly clean all mating surfaces, removing any old gasket material or corrosion.
7. Install New Components: Place the new gaskets, wear plate, and O-rings. Slide the new impeller into the housing while turning the driveshaft clockwise to bend the vanes correctly.
8. Reassemble Pump: Secure the new housing with its gasket and torque the bolts to the manufacturer's specification.
9. Reattach Lower Unit: Reinstall the lower unit to the engine, ensuring the driveshaft and water tube align correctly.
10. Final Checks: Refill the gearcase with fresh oil. Reconnect the battery.
11. Test Operation: Start the engine in a water supply (using "ear muffs" or in the water) and confirm a steady stream of water from the "tell-tale" cooling outlet.

Troubleshooting & FAQ

Q: How do I confirm this fits my engine?

A: The most reliable method is to match your engine's serial number to the ranges listed in the compatibility table. If you are unsure of your serial number, use the linked Mercury Serial Number Guide to locate it. Cross-referencing the OEM part number stamped on your old part with those listed is also a great way to confirm fitment.

Q: What are the common signs of a failing water pump impeller?

A: The most common sign is engine overheating, especially at low speeds or idle. Other indicators include a weak or non-existent water stream from the "tell-tale" outlet, or finding brittle, cracked, or deformed impeller vanes during a visual inspection.

Q: How often should I replace the impeller?

A: For preventative maintenance, it is recommended to inspect your water pump impeller annually and replace it every 1-2 years or every 100-200 hours of engine use. Service intervals should be shorter for boats operating in saltwater or sandy/silty conditions.

Q: OEM vs. Aftermarket?

A: 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.

Q: How fast do you ship and how much does it cost?

A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

Q: What is your warranty and return policy?

A: 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 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.