Water Pump Impeller Repair Kit – Fits Yamaha F50A 4-Stroke 50HP (Replaces 6BG-W0078-01)

Water Pump Impeller Repair Kit – Fits Yamaha F50A 4-Stroke 50HP (Replaces 6BG-W0078-01)

This water pump impeller repair kit is designed for Yamaha 4-Stroke 50 HP F50A models (1991–2007). It also serves as a compatible service part for select Yamaha E40X, 40X (2-Stroke), and F30A/F40B 4-Stroke models.

Engineered as a direct replacement for original equipment, this kit ensures proper fit and function, restoring your engine's cooling system performance. It is manufactured to meet or exceed OEM specifications.

• Installation: Direct OEM replacement parts for straightforward installation.
• Quality Standard: Produced in an ISO9002 certified factory to ensure reliable performance.
• Primary Components: Includes the essential impeller and gaskets for a standard service.

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

This kit contains the primary components required for a water pump service.

• 1 x Impeller (6H4-44352-02)
• 1 x Water Pump Repair Kit (6BG-W0078-00-00)

Note: When purchased as part of the comprehensive Yamaha Maintenance Kit for F50A (1991-2007), the following additional items are included:

• 2 x Drain Gaskets (90430-08020)
• 4 x Anodes (PAF4-04070003)
• 4 x Spark Plugs (NGKDPR6EB-9)
• 1 x Anode (62Y-11325-00A)
• 1 x Anode (67C-45251-00A)
• 1 x Anode (67C-45371-00A)
• 1 x Anode (688-45251-01A)
• 1 x Anode (6E0-45251-11A)
• 1 x Cotter Pin (91490-30025)
• 1 x Fuel Filter VST (6BG-13915-00)
• 1 x Fuel Filter (6C5-24251-00)
• 1 x Fuel Filter (6D8-WS24A-00)
• 1 x Gasket (PAF15-07010022)
• 1 x Oil Filter (5GH-13440-60)
• 1 x O-Ring (PAGB/T3452.1-32.5X1.8)
• 1 x Thermostat (PAF15-07000031)
• 1 x Washer (PAF15-04000003)

Installation Guide

1. Disconnect the negative battery cable and remove the engine cover.
2. Loosen the bolts securing the lower unit (gearcase) and carefully let it slide down.
3. Unscrew the bolts on the water pump housing cover to access the impeller.
4. Take note of the old impeller's vane direction before carefully prying it out.
5. Clean the housing interior and mating surfaces, removing any old gasket material or debris.
6. Install the new gasket, wear plate, and impeller, ensuring the impeller key is aligned.
7. Rotate the driveshaft clockwise while pushing the housing down to seat the impeller vanes correctly.
8. Secure the housing with its bolts and re-attach the lower unit to the engine.
9. Once assembled, use a water source (flushing muffs) to test for a strong water stream from the tell-tale outlet.

Troubleshooting & FAQ

Q: How do I confirm this kit fits my engine?

A: This kit is specified for Yamaha F50A models from 1991-2007. The best way to ensure compatibility is to verify your original part number against our cross-reference list (6BG-W0078-00-00, 6BG-W0078-01-00). You can also use the official Yamaha guides linked above to identify your exact model and required parts.

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

A: Key symptoms include the engine overheating, a weak or inconsistent water stream from the "tell-tale" outlet, or a melted water pump housing. Upon inspection, a worn impeller may have brittle, cracked, or missing vanes.

Q: How often should I replace the impeller?

A: As a general rule for preventative maintenance, we recommend replacing the impeller every 1 to 2 years or every 100-200 hours of operation. More frequent replacement may be necessary if you operate in sandy, silty, or saltwater conditions.

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.