Water Pump Repair Kit – Fits Johnson/Evinrude 35-60 HP (Replaces 439077, 396933, 18-3399)

Product Details

This Water Pump Repair Kit restores cooling system performance on the Johnson and Evinrude 35–60 HP 2-stroke outboard applications listed below. Fitment varies by horsepower and year, with listed applications spanning 1979–1994.

It replaces Johnson/Evinrude OEM references 439077, 396933, 777808, 396932, 391635, and 390770. Aftermarket references include Sierra 18-3399, GLM 12210, SEI 96-365-01BK, OBR JE-204, and Mallory 9-48207 / 9-48204.

• Engineered as a direct OEM-equivalent fit for the listed applications.
• Includes the pump housing, impeller, wear plate, and service hardware.
• Designed for the small water pump configuration with a plastic wedge-key impeller.
• Requires lubrication with silicone grease, glycerin, or dish soap during installation to ensure proper function (lubricant not included).

Part Number Matrix

Use this matrix to check OEM and aftermarket references. Compare the pump configuration and kit contents when replacing a kit supplied with or without a housing.

Engine & Model Compatibility

Confirm your engine model/year in the table below.

This kit is designed for specific Johnson and Evinrude 2-stroke outboards. Match the original part number, water pump configuration, and impeller key type before ordering.

Important: Match the small water pump and plastic wedge-key impeller configuration. For 3-cylinder loopcharged applications, the small gearcase is required. Horsepower and year alone do not confirm the pump configuration.

Technical Specs

Product Type

Water Pump Repair Kit with Housing

Installation

Direct-fit aftermarket replacement

Pump Configuration

Small water pump with plastic wedge-key impeller

Impeller Material

High-performance neoprene rubber

Product Dimensions

16.0" L × 12.5" W × 12.5" H

Other Technical Attributes

Requires lubrication with silicone grease, glycerin, or dish soap during installation (not included)

What’s in the Box

• 1 × Water pump housing assembly
• 1 × Impeller
• 1 × Wear plate
• 1 × Wear plate gasket
• Water tube grommet and sealing components
• Pump insert, mounting hardware, and small service components

Installation Notes

1. Disconnect the negative battery cable for safety.
2. Remove the lower unit (gearcase) from the outboard motor. This typically involves unbolting it from the driveshaft housing.
3. Unscrew the bolts securing the water pump housing and remove the old housing, impeller, and gaskets.
4. Thoroughly clean the mating surfaces, removing any old gasket material or sealant.
5. Lightly lubricate the new impeller and the inside of the new housing with a lubricant specified for impeller installation.
6. Install the new components in the reverse order of removal, ensuring the plastic wedge key is correctly seated and engaged with the impeller.
7. Re-install the lower unit, reconnect the battery, and test the engine using a water supply (flushing muffs) to confirm water is pumping correctly.

Troubleshooting & FAQ

How do I confirm this kit fits my specific engine model?

Match your engine's original part number with the Part Number Matrix, then check the horsepower and year range in the compatibility table. Confirm that your engine uses the small water pump with a plastic wedge-key impeller. For 3-cylinder loopcharged applications, also confirm the small gearcase configuration.

What are the signs of a failing water pump?

Common symptoms include the engine overheating at idle or low speeds, a weak or non-existent stream of water from the tell-tale outlet, and in severe cases, an engine alarm. The impeller is a wear item and can become brittle or lose blades over time, reducing its ability to pump water.

How often should a water pump impeller be replaced?

As a general maintenance rule, it is recommended to inspect the impeller annually and replace it every 1–2 years (or every 100–200 hours of use), regardless of its visible condition. Replacement frequency depends on usage (freshwater vs. saltwater) and operating conditions.

Why is lubrication necessary during installation?

Lubrication helps protect the impeller during assembly and initial operation. Use a lubricant suitable for impeller installation, and always provide cooling water before starting the engine. Do not run the pump dry.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

• Verify images/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 QC.