Water Pump Impeller – Fits Johnson/Evinrude 9.5/10 HP (Replaces 377178, 775519)

Water Pump Impeller – Fits Johnson/Evinrude 9.5/10 HP (Replaces 377178, 775519)

This high-quality water pump impeller is engineered for Johnson/Evinrude 9.5 HP (1964–1973) and 10 HP (1958–1963) 2-Stroke outboard engines. It ensures reliable water circulation to prevent engine overheating and maintain optimal performance.

It serves as a direct replacement for multiple OEM and aftermarket part numbers, including Johnson/Evinrude 377178, 775519, 777833, Sierra 18-3003, and others, guaranteeing a precise fit and function.

• Installation: Designed for a direct OEM replacement fit.
• Durable Construction: Made from high-quality neoprene rubber with a brass hub for corrosion resistance and longevity.
• Included Component: Package contains one water pump impeller.

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 Johnson/Evinrude owners, here’s a guide to help you identify your engine’s serial/model: Johnson/Evinrude Serial Number Guide.

Technical Specifications

Package Contents

• 1 x Water Pump Impeller (Replaces 377178/775519)

Installation Guide

1. Disconnect the battery and carefully remove the lower unit from the outboard motor.
2. Locate and unbolt the water pump housing.
3. Remove the old impeller, taking note of the original blade orientation. Clean any debris from the housing.
4. Inspect the housing, wear plate, and seals for damage or excessive wear.
5. Apply a light coat of marine-grade grease to the new impeller and the interior of the housing.
6. Install the new impeller into the housing, rotating the driveshaft clockwise to bend the blades into the correct position.
7. Reinstall the water pump housing and tighten the bolts to the manufacturer's recommended torque.
8. Reattach the lower unit to the outboard motor.
9. Once the engine is in water, start it and verify there is a steady stream of water from the cooling system's tell-tale outlet.

Troubleshooting & FAQ

How do I know if this impeller fits my Johnson/Evinrude engine?
This impeller is specifically designed for Johnson/Evinrude 9.5 HP (1964–1973) and 10 HP (1958–1963) 2-stroke models. The best way to confirm fitment is to check the "Compatible Engine Models" table and cross-reference your engine's model or original OEM part number (e.g., 377178, 775519).

What are the signs of a failed water pump impeller?
Common signs include the engine overheating, an alarm sounding, a weak or non-existent water stream from the "tell-tale" outlet, or finding cracked, brittle, or missing blades upon inspection.

How often should I replace my water pump impeller?
For preventative maintenance, it is recommended to inspect the impeller annually and replace it every 1-2 years. If you frequently operate in saltwater or sandy/silty conditions, more frequent replacement is advised to prevent unexpected engine overheating.

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.