Water Pump Impeller – Fits Mercury Marine 2/2.5/3/3.3/4/5/6 HP Outboards (Replaces 47-16154, 47-161543)

Water Pump Impeller – Fits Mercury Marine 2/2.5/3/3.3/4/5/6 HP Outboards (Replaces 47-16154, 47-161543)

This aftermarket water pump impeller is a direct replacement for several Mercury and Mariner outboard models. It is designed to fit specific 2-stroke engines from 3.3 HP to 5 HP (1987 and newer) and 4-stroke engines from 4 HP to 6 HP (1999 and newer).

It cross-references with multiple OEM and aftermarket part numbers, including Mercury 47-16154 and 47-161543, Sierra 18-3098, and Mallory 9-45302, ensuring broad compatibility for maintenance and repair.

• Installation Method: Direct replacement for the original impeller.
• Build Quality: The Sierra version (18-3098) is made in Italy and comes with a Limited Lifetime Warranty.
• Included Parts: Please see the "Package Contents" section for details, as included accessories may vary by brand.

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 Impeller (Replaces OEM 47-161543 / 47-16154)
• Please Note: The QuickMarine kit version is confirmed to include 1 x Gasket and 1 x Key Pin. It is not guaranteed that other aftermarket versions or the original OEM package include these additional components.

Installation Guide

1. Safety First: Disconnect the engine's battery before starting any work.
2. Remove Lower Unit: Unbolt and carefully detach the lower unit (gearcase) from the outboard's midsection.
3. Access the Pump: Locate and remove the bolts securing the water pump housing cover.
4. Remove Old Impeller: Take out the old impeller. Pay close attention to the orientation of the vanes as you remove it.
5. Clean and Inspect: Thoroughly clean the inside of the pump housing and inspect it for scoring, cracks, or heat damage.
6. Install New Impeller: Slide the new impeller onto the driveshaft. You may need to turn the shaft clockwise while pushing down to correctly bend the vanes into place.
7. Reassemble Pump: Replace any gaskets or seals, then reinstall the water pump housing and tighten the bolts to the manufacturer's specified torque.
8. Reinstall Lower Unit: Guide the lower unit back into place, ensuring the driveshaft and water tube align correctly, then secure it.
9. Test Operation: Reconnect the battery, start the engine in the water, and verify there is a strong, steady stream of water from the tell-tale outlet.

Troubleshooting & FAQ

How do I confirm this fits my engine?

First, check your engine's model, horsepower, and year against the "Compatible Engine Models" table. For Mercury engines, you can use the linked serial number guide to verify your exact model. Second, compare the part numbers in the "Part Number Cross-Reference" table with the number on your existing part if possible.

What are the signs of a failing impeller?

Common signs of a worn or failed impeller include the engine overheating, a weak or nonexistent water stream from the "tell-tale" cooling outlet, or, in severe cases, a melted water pump housing.

How often should I replace my water pump impeller?

For preventative maintenance, it is recommended to replace the impeller every 1-2 years or every 100-200 hours of use. Replacement frequency should be increased if you primarily operate in sandy, silty, or saltwater conditions.

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.