Water Pump Impeller Repair Kit – Fits Yamaha Outboard 4-5 HP (Replaces 68D-WG078-00-00, 6E0-W0078-A2-00)

Water Pump Impeller Repair Kit – Fits Yamaha Outboard 4-5 HP (Replaces 68D-WG078-00-00, 6E0-W0078-A2-00)

This water pump impeller repair kit is designed for select Yamaha and Mariner outboard motors. It provides a complete solution for servicing and restoring the engine's cooling system to prevent overheating and ensure reliable performance.

This kit is a direct replacement for Yamaha OEM part numbers 68D-WG078-00-00, 6E0-W0078-00, 6E0-W0078-A2-00, 6E0-W0078-A3-00, 6E0-W0078-A4-00, and 6E0-W0078-A5-00.

• Fits Yamaha 4-5 HP 2-Stroke (1984–2002) and F4 4-Stroke (1999–2008) models.
• Also compatible with Mariner 4-5 HP 2-Stroke outboards with serial numbers 6E0 & 6E3.
• Includes all necessary components for a full water pump rebuild: impeller, housing, plate, insert, gasket, and seals.

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 Outboard Motors

Mariner Outboard Motors

Technical Specifications

Package Contents

• 1 x Water Pump Impeller (6E0-44352-00-00)
• 1 x Water Pump Housing (68D-G4311-01-00)
• 1 x Cartridge Insert (6E0-44322-02-00)
• 1 x Outer Plate (6E0-44323-00-00)
• 1 x Gasket, Water Pump (68D-G4315-A0-00)
• 2 x Dowel Pin (93604-18080-00)
• 1 x Water Damper Seal (67D-44366-00-00)
• 4 x Bolt (97095-06045-00)

Installation Guide

1. Safety First: Disconnect the battery and ensure the engine is securely mounted in an upright position.
2. Access the Lower Unit: Locate and remove the bolts securing the lower unit (gearcase) to the engine's upper section.
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: The water pump housing is located on top of the gearcase. Remove the four bolts to lift the housing off.
5. Inspect and Replace Components: Remove the old impeller, gasket, wear plate, and seals. Note their orientation before removal.
6. Install New Parts: Clean all contact surfaces. Install the new components from the kit in the reverse order of removal. Lubricate the new impeller and housing interior with a light marine grease.
7. Align and Secure Housing: Ensure the impeller vanes are oriented correctly (in the direction of engine rotation) as you slide the housing down. Secure it with the new bolts and tighten to the manufacturer's specified torque.
8. Reinstall Lower Unit: Carefully guide the driveshaft back into the powerhead, ensuring the water tube aligns correctly. Secure the lower unit with its bolts.
9. Final Checks: Reconnect the battery and start the engine in a water source (using "ear muffs" or in a test tank). Check for a steady stream of water from the tell-tale outlet, indicating proper pump function.

Troubleshooting & FAQ

Q: How can I be sure this kit fits my Mariner engine?
A: For Mariner models, fitment depends on the engine's serial number. This kit is specifically for 4 HP models with serial number 6E0 and 5 HP models with serial number 6E3. Please verify your serial number before ordering to ensure compatibility.

Q: What are the signs that my water pump is failing?
A: Common symptoms of a failing water pump include a weak or non-existent water stream from the tell-tale outlet, engine overheating alarms, or a noticeable drop in engine performance. A worn impeller is the most common cause of these issues.

Q: How often should a water pump impeller be replaced?
A: As a preventative maintenance item, it is generally recommended to replace the water pump impeller every 1-2 years or every 100-200 hours of use, depending on operating conditions. More frequent replacement may be necessary if you operate in sandy or silty water.

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.