Water Pump Impeller Kit – Fits Mercury Marine 6-15 HP Outboards (Replaces 47-42038-2, 42038Q02, Sierra 18-3062)

Water Pump Impeller Kit – Fits Mercury Marine 6-15 HP Outboards (Replaces 47-42038-2, 42038Q02, Sierra 18-3062)

This water pump impeller kit is designed for Mercury Marine 6-15 HP 2-Stroke outboards (serial 0A197112 & up), 8-9.9 HP 4-Stroke models (2004 & prior), and 15 HP 4-Stroke models (323cc, 2008 & prior). It also fits select Force/Chrysler 9.9-15 HP outboards.

This kit serves as a direct replacement for Mercury Marine part numbers 47-42038-2, 47-420381, 47-42038Q02; GLM 89451; Mallory 9-45309/9-45309-10; and Sierra 18-3062.

• Installation Type: Direct OEM Replacement
• Impeller Material: Durable neoprene rubber compound for reliable performance
• Complete Kit: Includes the impeller, necessary gaskets, and an impeller key for a full-service replacement.

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 Neoprene Impeller (47-42038)
• 1 x Gasket (27-19202)
• 1 x Gasket (27-19204)
• 1 x Impeller Key

Installation Guide

1. Disconnect the battery and shift the outboard into neutral.
2. Remove the lower unit mounting bolts and carefully separate the lower casing from the upper housing.
3. Unbolt and remove the water pump housing cover to access the old impeller.
4. Note the rotational direction of the old impeller's vanes before removing it.
5. Remove the old impeller, impeller key, gaskets, and wear plate.
6. Thoroughly clean all mating surfaces, removing any old gasket material or debris.
7. Install the new gaskets and wear plate, ensuring they are correctly aligned.
8. Slide the new impeller key into the slot on the driveshaft.
9. Install the new impeller by pushing down while turning the driveshaft clockwise. This will help fold the vanes in the correct direction.
10. Reinstall the water pump housing and tighten its bolts to the manufacturer's specified torque.
11. Carefully reattach the lower unit to the upper engine housing, ensuring the driveshaft and shift shaft align properly.
12. Reconnect the battery. Before starting the engine, use a garden hose with an appropriate flush attachment to supply water to the lower unit. Check for a steady water stream from the engine's tell-tale port.

Troubleshooting & FAQ

Q: How do I confirm this fits my engine?

A: Check your engine's serial number. This kit is specified for Mercury 2-stroke outboards with serial numbers 0A197112 and up, and specific 4-stroke models by year. Always refer to our compatibility table and cross-reference your original part number to ensure a correct fit.

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, a melted water pump housing, or discovering a brittle, cracked, or deformed impeller during a visual inspection.

Q: How often should I replace the impeller?

A: For preventative maintenance, we recommend inspecting and/or replacing your water pump impeller every 1 to 2 years or every 100-200 hours of operation. This interval may be shorter depending on usage conditions (e.g., frequent use in sandy/silty water vs. clear 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.