Water Pump Impeller Kit – Fits Johnson/Evinrude 40-75 HP (Replaces 389133, 387326, 18-3325)

$56.90

Shipping calculated at checkout.

Water Pump Impeller Kit – Fits Johnson/Evinrude 40-75 HP (Replaces 389133, 387326, 18-3325) is backordered and will ship as soon as it is back in stock.

Worry-free returns

You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).

If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.

Delivery and Shipping

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This Water Pump Impeller Kit is designed for Johnson/Evinrude 40-75 HP 2-stroke outboard engines, covering models from 1960–1997. It is particularly suited for 2-cylinder and 3-cylinder Loopcharged models manufactured between 1975–1988.

This kit serves as a direct interchange for Johnson/Evinrude part numbers 389133, 387326, and 387217, as well as aftermarket references like GLM 12232 and Sierra 18-3325.

Direct OEM replacement for straightforward installation.
Manufactured in an ISO9002 certified factory to meet or exceed original equipment specifications.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand	Part Number
Johnson/Evinrude	389133
Johnson/Evinrude	387326
Johnson/Evinrude	387217
GLM	12232
Sierra	18-3325
Aftermarket	AM389133

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This kit is designed for a wide range of Johnson/Evinrude 2-stroke outboards, with specific applications for 2-cylinder and 3-cylinder Loopcharged models from 1975–1988.

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Johnson/Evinrude	Outboard	40	2-Stroke	1960–1997	389133, 387326
Johnson/Evinrude	Outboard	45	2-Stroke	1960–1997	389133, 387326
Johnson/Evinrude	Outboard	48	2-Stroke	1960–1997	389133, 387326
Johnson/Evinrude	Outboard	50	2-Stroke	1960–1997	389133, 387326
Johnson/Evinrude	Outboard	55	2-Stroke	1960–1997	389133, 387326
Johnson/Evinrude	Outboard	60	2-Stroke	1960–1997	389133, 387326
Johnson/Evinrude	Outboard	65	2-Stroke	1971–1978	389133, 387326	2-cyl models
Johnson/Evinrude	Outboard	70	2-Stroke	1971–1978	389133, 387326	3-cyl models
Johnson/Evinrude	Outboard	75	2-Stroke	1971–1978	389133, 387326	3-cyl models

Technical Specs

Product Type: Water Pump Impeller Kit
Installation: Direct OEM replacement
Other Technical Attributes: Manufactured to OEM specifications in ISO9002 certified factory

What’s in the Box

1 x Water Pump Impeller (389133)

Installation Notes

Disconnect the battery and remove the engine cover.
Locate and unbolt the lower unit (gearcase) from the upper engine casing.
Carefully lower the gearcase to access the water pump housing.
Remove the water pump housing cover to expose the impeller.
Note the orientation of the old impeller fins before removing it.
Clean all component surfaces and install the new impeller and any included gaskets or seals.
Reassemble the water pump housing and torque bolts to manufacturer specifications.
Reinstall the lower unit, ensuring the driveshaft and water tube align correctly.
After reassembly, test the engine in a suitable water source and verify a strong, steady stream from the water pump indicator (tell-tale).

Troubleshooting & FAQ

How do I know if this kit fits my specific engine model?

This kit fits most Johnson/Evinrude 40-75 HP 2-stroke outboards from 1960–1997. It is specifically designed for 2-cylinder (40-60 HP) and 3-cylinder (60-75 HP) Loopcharged models from 1975–1988. The most reliable method is to match your engine's original part number to one listed in our Part Number Matrix, such as 389133 or 387326.

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 port, frequent engine overheating alarms, or, in severe cases, a melted water pump housing. Reduced engine performance at high RPMs can also indicate poor cooling.

How often should I replace my impeller?

For preventative maintenance, we recommend inspecting and/or replacing the impeller every 1-2 years or every 100-200 hours of operation. Service intervals should be shorter if you operate primarily in saltwater or sandy/silty conditions.

Is this kit difficult to install?

Installation is straightforward for those with mechanical experience but requires removing the lower unit (gearcase). If you are not comfortable with this process, we recommend professional installation to ensure correct assembly and function.

What’s the difference between OEM and this aftermarket part?

This listing is an aftermarket replacement (not OEM). It's built to OEM-level specifications with comparable materials. All our parts are manufactured in an ISO 9002 facility and are batch-inspected for quality and consistency.

How fast is shipping?

We ship worldwide quickly—typical transit is 5–15 days. Standard shipping is free to most regions, and expedited options will appear at checkout if available for your location.

What is your warranty and return policy?

This part is covered by a 1-year warranty against manufacturing defects under normal use. If you encounter an issue, please contact our support team with your order details. Returns are accepted within our standard window for unused items in their original condition. See our full policy page or reach out for instructions.

Safety & Important Info

Verify images and specifications against your original part. If anything differs—even if your model appears compatible—do not purchase.
This is an aftermarket replacement, not an OEM component.
Professional installation is recommended for safety and performance.

About Sea Sierra

Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
Manufacturer-Direct Value — Fair pricing without compromising on materials or quality control.

Payment & Security

Payment methods

Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.