Water Pump Impeller Repair Kit with Housing – Fits Johnson/Evinrude 40–55 HP 2-Stroke Outboards (Replaces 439077, 396933)
Water Pump Impeller Repair Kit with Housing – Fits Johnson/Evinrude 40–55 HP 2-Stroke Outboards (Replaces 439077, 396933) is backordered and will ship as soon as it is back in stock.
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Water Pump Impeller Repair Kit with Housing – Fits Johnson/Evinrude...
Water Pump Impeller Repair Kit with Housing – Fits Johnson/Evinrude 40–55 HP 2-Stroke Outboards (Replaces 439077, 396933) is backordered and will ship as soon as it is back in stock.
Product Details
This water pump impeller repair kit with housing is designed for selected Johnson/Evinrude 2-stroke outboard applications using the small gearcase and plastic wedge key water-pump configuration. Catalog references place this application in the 1984–1994 range and include selected 40, 45, 50, and 55 HP models. Confirm the exact model, year, gearcase configuration, and original part number before ordering.
The kit replaces Johnson/Evinrude OEM references 439077, 0439077, and 396933. Sierra reference 18-3399 is an aftermarket cross-reference for a water pump kit with housing. These numbers are reference identifiers only; they do not replace model-specific fitment verification.
- Complete water pump service kit with replacement housing.
- Includes an impeller, housing, wear plate, seals, gaskets, grommets, keys, and mounting hardware as listed below.
- Designed for selected Johnson/Evinrude 2-stroke outboards with the applicable small-gearcase water pump configuration.
Part Number Matrix
Use the following references to compare your original component and confirm compatibility.
| Brand | Part Number | Reference |
|---|---|---|
| Johnson/Evinrude | 439077 / 0439077 | OEM replacement reference |
| Johnson/Evinrude | 396933 | OEM replacement reference |
| Sierra | 18-3399 | Aftermarket water pump kit with housing reference |
Engine & Model Compatibility
The compatibility range below reflects the available catalog application information for the 439077 water-pump configuration. Because Johnson/Evinrude fitment depends on gearcase and water-pump design as well as horsepower and year, verify the complete model number before installation.
| Brand | Engine application | Rated HP | Stroke | Years | OEM reference | Configuration note |
|---|---|---|---|---|---|---|
| Johnson/Evinrude | Selected 2- and 3-cylinder loop-charged outboards | 40 | 2-Stroke | 1984–1994 application range | 439077 / 0439077 | Small gearcase with small water pump and plastic wedge key; verify exact model. |
| Johnson/Evinrude | Selected 2- and 3-cylinder loop-charged outboards | 45 | 2-Stroke | 1984–1994 application range | 439077 / 0439077 | Small gearcase with small water pump and plastic wedge key; verify exact model. |
| Johnson/Evinrude | Selected 2- and 3-cylinder loop-charged outboards | 50 | 2-Stroke | 1984–1994 application range | 439077 / 0439077 | Small gearcase with small water pump and plastic wedge key; verify exact model. |
| Johnson/Evinrude | Selected 2- and 3-cylinder loop-charged outboards | 55 | 2-Stroke | 1984–1994 application range | 439077 / 0439077 | Small gearcase with small water pump and plastic wedge key; verify exact model. Some model-year configurations may differ. |
Technical Specs
- Product Type
- Water pump impeller repair kit with housing
- Application
- Selected Johnson/Evinrude 2-stroke outboards
- Installation
- Direct replacement when the original water-pump configuration and part number match
- Water Pump Configuration
- Small gearcase, small water pump, plastic wedge key application
- Housing Material
- Metal alloy housing with neoprene rubber components
- Housing Color
- Silver/black
- Fitting Type
- Direct fit for listed applications after model verification
What’s in the Box
- 1 x Water pump impeller (777214/396809)
- 2 x Impeller key wedge
- 1 x Water pump housing (384087/18-3336)
- 1 x Liner (320775)
- 1 x Plate (320776)
- 1 x Wear plate (320981/18-3343)
- 1 x Gasket (336530/18-2709)
- 1 x O-ring (339543/303059/18-7134)
- 1 x Water-tube grommet (315837/18-3337)
- 1 x Housing grommet (341732)
- 1 x Seal (315788)
- 1 x Bracket (315838)
- 2 x Short screw (319126/18-3369)
- 2 x Long screw (909533/18-3365)
Installation Notes
- Disconnect the battery cables and allow the engine to cool completely.
- Remove the lower unit or gearcase according to the engine service procedure.
- Remove the old water-pump housing and expose the impeller and related components.
- Note the orientation of the old components and the position of the impeller key before disassembly.
- Clean all mating surfaces and remove old gasket material, debris, and corrosion.
- Install the new plate, wear plate, seals, gaskets, grommets, and other supplied components in the correct order.
- Install the impeller on the driveshaft, align the keyway, and use the key that matches the engine configuration.
- Lubricate the impeller and housing with a lubricant suitable for marine water-pump service.
- Install the new housing and tighten fasteners to the engine manufacturer’s specified torque.
- Reinstall the lower unit and reconnect the battery only after the assembly is complete.
- Run the engine using the proper test procedure and confirm a strong, steady tell-tale stream. Stop immediately if the engine overheats or water flow is abnormal.
Troubleshooting & FAQ
How do I confirm that this kit fits my engine?
Compare your complete engine model number, year, horsepower, stroke, gearcase configuration, and original water-pump part number with the compatibility information on this page. The 439077 application is associated with a small gearcase, small water pump, and plastic wedge key. Do not rely on horsepower alone.
What are the signs of a failing water-pump impeller?
Common signs include weak or absent tell-tale water flow, overheating, an overheating alarm, or reduced cooling performance. A removed impeller may show cracked, brittle, distorted, or missing vanes.
How often should the impeller be inspected?
Inspect the water-pump components during scheduled maintenance and whenever cooling performance changes. Replacement intervals depend on operating hours, storage conditions, and exposure to saltwater, sand, or silt.
Is this a complete kit with a housing?
Yes. This listing is for a water pump repair kit with a replacement housing and the components listed in the “What’s in the Box” section.
Why are two impeller key wedges included?
The supplied kit includes two key wedges as listed. Before installation, compare them with the original key and use the component that matches the engine’s driveshaft and impeller configuration.
Is this an OEM part?
No. This is an aftermarket replacement kit intended to replace the listed Johnson/Evinrude OEM references. Johnson/Evinrude, OMC, Sierra, and other referenced names and numbers are used only for identification and compatibility comparison.
Safety & Important Information
- Confirm the complete model number, year, horsepower, stroke, gearcase configuration, and original part number before purchase.
- Do not install the kit if the original housing, key, impeller, or water-pump layout differs from the supplied components.
- Follow the engine manufacturer’s service instructions and torque specifications.
- Professional installation is recommended if you are not experienced with outboard lower-unit service.
About Sea Sierra
- Marine Replacement Parts — Replacement components for selected outboard maintenance and repair applications.
- Application-Focused Listings — Compatibility information is organized by engine brand, horsepower, stroke, year, and component configuration.
- Support for Installation Verification — Compare your original part and complete engine model before ordering or installing.
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