Water Pump Impeller Kit – Fits Mercury/Mariner 6-15 HP Outboards (Replaces 47-42038-2, 47-42038Q02)

Water Pump Impeller Kit – Fits Mercury/Mariner 6-15 HP Outboards (Replaces 47-42038-2, 47-42038Q02)

This water pump impeller is designed for a range of Mercury/Mariner outboard motors, including 2-Stroke 6-15 HP models (1986 and up) and 4-Stroke 8-15 HP models (up to 2005) that have a standard gearcase.

It serves as a direct replacement for multiple OEM and aftermarket part numbers, including Mercury 47-42038-2 / 47-42038Q02, Sierra 18-3062, Mallory 9-45039, and CEF 500318.

• Engineered with a durable neoprene marine rubber compound for reliable performance.
• Features a 6-blade design with a plastic hub for efficient water circulation.
• Installation is straightforward as a direct OEM-equivalent 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.

Technical Specifications

Package Contents

• 1 x Neoprene Impeller (Replaces 47-42038-2)
• 1 x Gasket (Replaces 27-19202)
• 1 x Gasket (Replaces 27-19204-3)
• 1 x Impeller Key

Installation Guide

Professional installation is recommended. The following are general, non-comprehensive steps:

1. Disconnect the battery and remove the engine cover.
2. Shift the outboard into neutral.
3. Remove the bolts securing the lower unit (gearcase) to the engine.
4. Carefully lower and separate the gearcase from the upper housing. Be mindful of the shift shaft.
5. Locate the water pump housing on top of the gearcase and remove its mounting bolts.
6. Slide the housing up to expose the old impeller. Note the orientation of the old impeller's blades.
7. Remove the old impeller, key, gaskets, and wear plate. Clean all surfaces thoroughly.
8. Install the new gasket, wear plate, and impeller key.
9. Slide the new impeller onto the drive shaft while turning the shaft clockwise to bed the vanes properly.
10. Apply a light marine lubricant to the inside of the housing and reinstall it.
11. Reassemble the gearcase to the engine, ensuring the water tube and shift shaft align correctly.
12. Test the engine using a water source (flusher or test tank) to confirm proper water flow.

Troubleshooting & FAQ

Q: How do I confirm this impeller fits my specific engine?

A: The best way to confirm fitment is by checking your original part number. This impeller replaces Mercury part numbers 47-42038-2 and 47-42038Q02, among others. You should also cross-reference your engine's model, year, and serial number against our compatibility table. When in doubt, consult your service manual or a professional mechanic.

Q: What are the signs of a worn or failing water pump impeller?

A: Common signs include the engine overheating at idle or low speeds, a weak or non-existent stream of water from the "tell-tale" port, and visible damage to the old impeller upon inspection (e.g., cracked, brittle, or missing blades).

Q: How often should I replace the water pump impeller?

A: For preventative maintenance, it is recommended to inspect the impeller annually and replace it every 1-2 years, depending on usage (hours) and operating conditions (saltwater vs. freshwater). An impeller that has been sitting dry for a long period may also become stiff and should be replaced.

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.