Water Pump Impeller – Fits Mercury/Mariner/Honda 40-300HP (Replaces 47-43026T2)

Water Pump Impeller – Fits Mercury/Mariner/Honda 40-300HP (Replaces 47-43026T2)

This water pump impeller is designed for a wide range of Mercury/Mariner/Honda 40-300HP outboards and MerCruiser sterndrives with applicable water pumps. It serves as a reliable replacement to maintain your engine's cooling system performance.

This part is a direct replacement for Mercury 47-43026T2, Sierra 18-3056, Mallory 9-45037, and EMP 47-01814.

• Easy to install as a direct replacement part.
• Features a 6-blade design constructed from durable, heat-resistant rubber.
• Requires drive key P/N 28-32833 for installation (not included).

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.

Confirm your engine model/year in the table below.

Technical Specifications

Package Contents

• 1 x Water Pump Impeller (Replaces 47-43026T2)

Installation Guide

1. Disconnect Power: Disconnect the negative battery cable before starting work.
2. Access Lower Unit: Remove the bolts securing the lower unit (gearcase) and carefully lower it from the engine's midsection.
3. Remove Pump Housing: Locate and unbolt the water pump housing cover.
4. Inspect and Remove Old Impeller: Note the rotational direction of the old impeller's blades before pulling it off the driveshaft. Remove the old drive key.
5. Clean Surfaces: Thoroughly clean the inside of the pump housing and the base plate, removing any old gasket material or debris.
6. Install New Impeller: Insert the new drive key into the driveshaft keyway. Lubricate the new impeller with a marine-safe lubricant and slide it onto the shaft, rotating it in the direction of engine operation to correctly orient the blades.
7. Reassemble Pump: Reinstall the housing and tighten the bolts to the manufacturer's recommended torque.
8. Reinstall Lower Unit: Carefully guide the lower unit back into place, ensuring the driveshaft, shift shaft, and water tube align correctly. Secure it with the bolts.
9. Test Operation: Reconnect the battery. With the engine in a water source (using flush muffs or in the water), start it and confirm a steady stream of water is exiting the tell-tale port.

Troubleshooting & FAQ

Q: How can I be sure this impeller fits my specific engine model?

A: Check the compatibility table and cross-reference your engine's original part number with the numbers listed (Mercury 47-43026T2, Sierra 18-3056). For Mercury engines, use the serial number guide linked above to verify your model and year range.

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

A: Common signs include the engine overheating, a weak or non-existent water stream from the "tell-tale" outlet, and a dry, cracked, or brittle appearance on the old impeller upon inspection.

Q: How often should I replace the water pump impeller?

A: For preventative maintenance, it is best practice to replace the impeller every 1-2 years or every 100-200 hours of use, depending on operating conditions (e.g., saltwater vs. freshwater).

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.