Water Pump Repair Kit - Fits Yamaha 4.2L V6 225HP-300HP (Replaces 6CE-W0078-01-00, 6CE-W0078-02-00)

Water Pump Repair Kit - Fits Yamaha 4.2L V6 225HP-300HP (Replaces 6CE-W0078-01-00, 6CE-W0078-02-00)

This water pump repair kit is designed for Yamaha 4-Stroke 4.2L V6 outboard engines, including 225HP, 250HP, 300HP, and 350HP models from 2007 to 2015. It also fits the VF250 SHO model from 2015. The kit provides all the necessary components for a complete and reliable service of your lower unit's water pump.

It serves as a direct replacement for Yamaha part numbers 6CE-W0078-01-00 and 6CE-W0078-02-00, as well as Sierra equivalents 18-3470 and 18-3471.

• Includes all required gaskets, seals, impeller, and hardware for a full rebuild.
• Engineered to meet or exceed OEM specifications for fit and performance.
• Installs in the lower unit to restore cooling system efficiency.

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.

Technical Specifications

Package Contents

• 1 x Impeller (6CE-44352-00-00)
• 1 x Key/Woodruff Key (90280-04M05-00/90280-04002-00)
• 1 x O-Ring (93210-94003-00)
• 4 x Bolt (97095-08045-00/90119-08191-00)
• 2 x Seal, Oil (93104-22M07-00)
• 1 x Insert/Cartridge (6AW-44322-00-00)
• 1 x Outer Plate/Cartridge Plate (6CE-44323-01-00)
• 1 x Water Pump Gasket (6CE-44315-00-00)
• 2 x Dowel Pin (93606-12019-00)
• 1 x O-Ring (93210-37M67-00)

Installation Guide

1. Disconnect the battery and shift the outboard into neutral. Drain the gearcase oil from the lower unit.
2. Remove the bolts securing the lower unit to the midsection and carefully detach the lower unit.
3. Unbolt and remove the water pump housing to access the old impeller and other components.
4. Thoroughly clean the mating surfaces of the housing and lower unit, removing any old gasket material or debris.
5. Install the new water pump gasket, outer plate, woodruff key, and impeller onto the driveshaft.
6. Lubricate the inside of the new insert/cartridge and slide the housing over the impeller, ensuring the impeller vanes are oriented correctly.
7. Install the new seals in the housing and tighten the bolts to the manufacturer's specified torque.
8. Reinstall the lower unit, ensuring the driveshaft, shift shaft, and water tube are properly aligned.
9. Refill the lower unit with the correct type and amount of gearcase lubricant.
10. Reconnect the battery and test the engine's cooling system using a flush attachment, checking for a strong, steady stream of water.

Troubleshooting & FAQ

How do I confirm this kit fits my specific engine?
First, check your engine's model and year against the "Compatible Engine Models" table. For Yamaha owners, we provide a Serial Number Guide and Parts Diagrams to help you verify part numbers and compatibility with absolute certainty.

What are the common signs that my water pump needs replacement?
The most common symptoms of a failing water pump are an overheating engine alarm and a weak or inconsistent stream of water from the "tell-tale" outlet. Reduced engine performance at high RPMs can also indicate a cooling problem.

How often should I replace the water pump or impeller?
For preventative maintenance, it is recommended to inspect and likely replace the water pump impeller every 1 to 2 years or every 100-200 hours of use, especially if operating frequently in saltwater or sandy/silty conditions. This complete kit ensures all wear items are replaced at once.

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.