Water Pump Impeller – Fits Mercury Marine 30-300 HP & MerCruiser Alpha One Gen 2 (Replaces 47-43026T2)

Water Pump Impeller – Fits Mercury Marine 30-300 HP & MerCruiser Alpha One Gen 2 (Replaces 47-43026T2)

This water pump impeller is designed for a wide range of Mercury Marine outboards from 30 to 300 HP, including 4-stroke Bigfoot models and 3.0L engines (1990s–present). It also fits MerCruiser Alpha One Generation 2 stern drives (S/N D494569 & above, 1991–present) and select Chrysler/Force 75-120 HP outboards (1995-1999).

As a direct replacement for multiple OEM and aftermarket part numbers, this impeller ensures reliable performance for your engine's cooling system. It is engineered to meet or exceed original equipment specifications.

• Installation Method: Direct Replacement
• Material: Durable neoprene rubber compound (Marine Grade CR Rubber) with 6 blades.
• Package Includes: 1x Impeller, 1x Impeller Key, 2x Gaskets.

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.

Mercury Marine Outboards

MerCruiser Stern Drives

Chrysler/Force Outboards

Technical Specifications

Package Contents

• 1 x Water Pump Impeller (47-43026T2)
• 1 x Impeller Key (28-43037)
• 2 x Gaskets (Seals)

Installation Guide

1. Disconnect Power: Disconnect the engine's battery cables to prevent accidental starting.
2. Remove Lower Unit: Unbolt and carefully lower the gearcase (lower unit) from the outboard leg or sterndrive.
3. Access Pump Housing: Locate and remove the bolts securing the water pump housing. Slide the housing up and off the driveshaft.
4. Inspect and Remove Old Impeller: Note the rotational direction of the old impeller's blades. Remove the old impeller, the impeller key, and the upper/lower gaskets.
5. Clean Surfaces: Thoroughly clean the inside of the pump housing and the wear plate. Inspect for scoring or warping; replace if significant wear is found.
6. Install New Components: Place the new lower gasket and wear plate. Insert the new impeller key into the driveshaft slot.
7. Install New Impeller: Align the keyway in the new impeller with the key on the driveshaft. Push the impeller down while turning the driveshaft clockwise to correctly bend the blades inside the housing.
8. Reassemble Pump: Apply the new upper gasket and reinstall the water pump housing. Tighten the bolts to the torque specified by the manufacturer.
9. Reinstall Lower Unit: Guide the lower unit back into position, ensuring the driveshaft, shift shaft, and water tube are properly aligned. Securely fasten the mounting bolts.
10. Test Operation: Reconnect the battery, start the engine in water, and confirm a steady stream of water is exiting the "tell-tale" port.

Troubleshooting & FAQ

How do I confirm this fits my engine?
To ensure compatibility, check your engine's model, year, and serial number against our "Compatible Engine Models" tables. For MerCruiser Alpha One Gen 2 drives, this part is specifically for units with serial numbers D494569 and above. We strongly recommend cross-referencing your old part number with the list in the "Part Number Cross-Reference" section.

What are the signs of a failing water pump impeller?
Common symptoms include the engine overheating at idle or low speeds, a weak or intermittent water stream from the "tell-tale" outlet, and a melted water pump housing. Upon inspection, a failed impeller may have brittle, cracked, or missing blades.

How often should I replace the impeller?
As a preventative maintenance measure, we recommend inspecting the impeller annually and replacing it every 1-2 years or every 100-200 hours of use. Replacement frequency should be increased if you operate in saltwater or water with high levels of sand or silt.

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