Water Pump Impeller – Fits Mercury/Mariner 6-15 HP Outboards (Replaces 47-42038Q02, 42038Q02)

Water Pump Impeller – Fits Mercury/Mariner 6-15 HP Outboards

This water pump impeller is a direct replacement for various Mercury and Mariner outboard engines. It is designed to fit 2-stroke outboards from 6 to 15 HP (1986-2005, serial number 0A197112 & up) and 4-stroke outboards including 8/9.9 HP (2004 & prior) and 15 HP (323cc, MY2008 & prior).

This component is a direct replacement for Mercury part numbers 47-42038-2, 47-42038Q02, and 47-42038Q03, as well as several aftermarket equivalents.

• Features a durable neoprene rubber housing with a metal hub for reliable performance.
• Engineered with a 6-blade design for efficient water circulation.
• Installs in a standard gearcase.

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.

Mercury/Mariner Outboards

Force Outboards

Technical Specifications

Package Contents

Package contents depend on the option selected:

• Impeller Only (47-42038Q02):
  1 x Neoprene Impeller
• Repair Kit (47-42038Q03/47-42038T3):
  1 x Neoprene Impeller (47-42038-2)
  1 x Gasket (27-19202)

Installation Guide

1. Disconnect the spark plug wires and the battery.
2. Shift the outboard into the neutral position.
3. Remove the bolts securing the lower unit (gearcase) to the upper leg.
4. Carefully lower and remove the gearcase from the driveshaft housing.
5. Unbolt and remove the water pump housing cover to access the impeller.
6. Take note of the rotational direction of the existing impeller blades before removing it.
7. Thoroughly clean the inside of the pump housing and the wear plate.
8. Install the new impeller, twisting it in the direction of normal engine rotation to seat the blades correctly.
9. Install the new gaskets and reassemble the pump housing.
10. Tighten the housing bolts to the manufacturer's specified torque.
11. Reinstall the lower unit, ensuring the driveshaft, shift shaft, and water tube are correctly aligned.
12. Once assembled, test the engine in water to confirm proper water flow from the tell-tale outlet.

Troubleshooting & FAQ

How do I confirm this impeller fits my Mercury engine?
First, check the compatibility tables on this page. For these Mercury/Mariner models, verifying the serial number is critical. The impeller fits 2-Stroke models (6-15 HP) with serial number 0A197112 & up and specific 4-Stroke models within the listed year and serial ranges. To be certain, use our Mercury Serial Number Guide to identify your engine.

What are the signs of a failing water pump impeller?
Common symptoms include the engine overheating, a weak or intermittent water stream from the tell-tale (pee) outlet, or a complete lack of water flow. A visual inspection may reveal cracked, brittle, or worn-down rubber blades.

How often should I replace the impeller?
For preventative maintenance, it is recommended to inspect the impeller annually and replace it every 1-2 years or after every 100-200 hours of operation. Replacement frequency should be increased if you operate in saltwater or in water with heavy sediment.

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.