Water Pump Impeller – Fits Yamaha 6HP & 8HP 2-Stroke Outboards (Replaces 6G1-44352-00-00)

Water Pump Impeller – Fits Yamaha 6HP & 8HP 2-Stroke Outboards

This water pump impeller is designed for Yamaha 6HP and 8HP 2-stroke outboard engines manufactured from 1984 to 2009. It also fits select Mariner 6C, 6D, and 8C 2-stroke models.

This component serves as a direct replacement for multiple OEM and aftermarket part numbers, including Yamaha 6G1-44352-00-00, Sierra 18-3066, and Mercury/Mariner 47-11590M.

• Engineered for direct installation.
• Constructed from durable neoprene rubber with a hardened nylon hub.
• Includes one water pump impeller.

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 Yamaha owners, here’s a guide to help you identify your engine’s serial/model: Yamaha Serial Number Guide. You can also review exploded diagrams to verify part numbers: Yamaha Parts Diagrams & Catalog.

Yamaha Outboards

Confirm your engine model/year in the table below.

Mariner Outboards

Technical Specifications

Package Contents

• 1 x Water Pump Impeller (6G1-44352-00-00/47-11590M)

Installation Guide

1. Disconnect the Battery: Ensure the engine is off and disconnect the battery terminals to prevent accidental starting.
2. Access the Lower Unit: Remove the bolts securing the lower unit (gearcase) to the upper driveshaft housing.
3. Remove the Lower Unit: Carefully lower the gearcase away from the engine. The driveshaft will disengage from the powerhead.
4. Open the Water Pump Housing: Locate the water pump housing on top of the gearcase and remove its mounting bolts.
5. Remove the Old Impeller: Lift the housing cover to expose the impeller. Note the rotational direction of the old impeller blades before removing it from the driveshaft.
6. Clean and Inspect: Clean any debris or corrosion from the housing, wear plate, and cup. Inspect for deep grooves or damage.
7. Prepare for Installation: Apply a light coat of silicone grease, glycerine, or dish soap to the inside of the pump housing and to the new impeller.
8. Install the New Impeller: Slide the new impeller onto the driveshaft. Rotate the driveshaft in its normal operating direction (usually clockwise) to fold the blades into the correct orientation as you push the housing down over it.
9. Reassemble the Housing: Secure the water pump housing with its bolts, ensuring a proper seal.
10. Reattach the Lower Unit: Raise the lower unit back into place, aligning the driveshaft, shift shaft, and water tube. Reinstall and tighten the mounting bolts.
11. Test the System: Reconnect the battery. Start the engine in a test tank or with a water flusher to verify that water is exiting the "telltale" outlet.

Troubleshooting & FAQ

How do I confirm this impeller fits my engine?
First, check the "Compatible Engine Models" tables on this page. For Yamaha and Mariner owners, we provide links to serial number guides that can help you verify your engine's model and year. Cross-referencing your existing part number with our "Part Number Cross-Reference" table is the most reliable method.

How often should a water pump impeller be replaced?
As a general maintenance guideline, impellers should be inspected annually and replaced every 1-2 years, or every 100-200 hours of use, depending on operating conditions. Operation in sandy or silty water may require more frequent replacement.

What are the signs of a failing water pump impeller?
The most common symptoms include engine overheating at idle or low speeds, a weak or non-existent water stream from the telltale outlet, and in severe cases, a high-temperature alarm from your engine's monitoring system.

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.