Water Pump Impeller – Fits Johnson/Evinrude 10-35 HP (Replaces 375638, 775518)

Water Pump Impeller – Fits Johnson/Evinrude 10-35 HP (Replaces 375638, 775518)

This water pump impeller is designed for a wide range of Johnson/Evinrude 10-35 HP 2-stroke outboard engines manufactured between 1949 and 1978. It covers specific models including 10 HP (1949–1957), 15/18 HP (1953–1973), 20/25 HP (1966–1978), and 35 HP (1970–1978).

It serves as a direct replacement for multiple OEM and aftermarket part numbers, ensuring broad compatibility for engine maintenance and repair.

• Engineered for direct, hassle-free installation.
• Constructed with a durable neoprene impeller and a solid brass hub.
• Designed to meet or exceed original equipment specifications for reliable cooling performance.

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 Serial Number Guide.

Technical Specifications

Package Contents

1 x Water Pump Impeller (375638/775518)

Installation Guide

1. Disconnect the negative battery cable and shift the outboard into the neutral position.
2. Unbolt and remove the lower unit (gearcase) from the upper engine housing.
3. Locate the water pump, which is typically on top of the lower unit, and remove its housing bolts.
4. Carefully lift the pump housing and slide the old impeller off the drive shaft. Note the rotational direction of the old impeller's blades.
5. Clean the inside of the housing and the base plate, inspecting for any scoring, warping, or corrosion.
6. Lightly lubricate the new impeller with marine grease and slide it onto the drive shaft.
7. Turn the drive shaft clockwise while pressing down on the impeller to correctly seat the blades inside the housing.
8. Reinstall the water pump housing, ensuring a proper seal, and tighten the bolts to the manufacturer's specified torque.
9. Reattach the lower unit to the engine, making sure the drive shaft and water tube align correctly, and secure the bolts.
10. Reconnect the battery and test the engine using a water supply (flushing muffs or in water) to verify a strong stream from the tell-tale port.

Troubleshooting & FAQ

How do I confirm this fits my engine?
This impeller fits a wide range of Johnson/Evinrude 10-35 HP 2-stroke outboards from 1949–1978. To ensure a correct fit, please check the "Compatible Engine Models" table and cross-reference your engine's model and year. Verifying your original part number against our "Part Number Cross-Reference" list is the most reliable method.

What are the signs of a failing water pump impeller?
Common signs include a weak or non-existent water stream from the engine's tell-tale outlet, engine overheating alarms, steam from the exhaust, or a noticeable decrease in engine performance.

How often should I replace the water pump impeller?
For preventative maintenance, it is recommended to inspect and replace the impeller annually or every 100 hours of use, whichever comes first. This interval may be shorter if you frequently operate in sandy, silty, or saltwater conditions.

Is this an OEM part?
This listing is for an aftermarket replacement part, not an OEM component. We build our parts to meet or exceed OEM specifications using high-grade materials. Production is completed in an ISO9001-certified facility, and each batch is inspected to ensure consistent quality and performance.

How fast do you ship and how much does it cost?
We offer fast global shipping, with most orders arriving within 5–15 days worldwide. Standard shipping is free for all orders. Expedited options are available at checkout and vary by location.

What is your warranty and return policy?
This product includes a 1-year warranty against manufacturing defects under normal use. If you encounter an issue, contact our support team with your order details. Returns are accepted within our standard return window for unused items in their original condition; please see our official policy page or reach out for instructions.

Important Notes

• Before purchasing, please verify that the product images, specifications, and listed part numbers 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 manufactured by the original equipment manufacturer (OEM).
• Professional installation is recommended to ensure safety, proper function, and optimal performance. Damage from improper installation is not covered by the warranty.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply leading marine service brands globally with parts they can rely on.
• Fast Global Shipping: We provide free delivery worldwide from our international warehouses, typically within 5–15 days.
• Direct from Manufacturer: By cutting out the middleman, we offer competitive pricing without ever compromising on quality or performance.