Water Pump Impeller for Evinrude Johnson V4 V6 V8 | 85HP-235HP Outboard Motors
This high-quality aftermarket water pump impeller is designed to fit Evinrude Johnson V4, V6, and V8 outboard motors ranging from 85HP to 235HP. Engineered to meet OEM specifications, this impeller ensures reliable cooling system performance for your outboard engine, preventing overheating and maintaining optimal operating temperatures during operation.
This impeller directly replaces OEM part numbers 389642, 777212, and 0777212, as well as aftermarket equivalent Sierra 18-3043. It is specifically compatible with Evinrude Johnson V4 and V6 outboard motors manufactured between 1973 and 1978.
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6-blade design for efficient water flow and cooling performance
- Precision-molded to OEM dimensions for reliable fitment
- Direct replacement for multiple OEM and aftermarket part numbers
Part Number Cross-Reference
Use this table to confirm equivalent part numbers across OEM and aftermarket brands.
| Brand |
Part Number |
| Johnson/Evinrude/OMC/BRP |
389642 |
| Johnson/Evinrude/OMC/BRP |
777212 |
| Johnson/Evinrude/OMC/BRP |
0777212 |
| Sierra |
18-3043 |
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.
| Brand |
Model |
Rated HP |
Years |
| Evinrude Johnson |
V4 / V6 |
85HP |
1973-1978 |
| Evinrude Johnson |
V4 / V6 |
115HP |
1973-1978 |
| Evinrude Johnson |
V4 / V6 |
135HP |
1973-1976 |
| Evinrude Johnson |
V4 / V6 |
140HP |
1977-1978 |
| Evinrude Johnson |
V4 / V6 |
150HP |
1976-1978 |
| Evinrude Johnson |
V4 / V6 |
175HP |
1976-1978 |
| Evinrude Johnson |
V4 / V6 / V8 |
200HP |
1976-1978 |
| Evinrude Johnson |
V8 |
235HP |
1978 |
Technical Specifications
| Specification |
Value |
| Number of Blades |
6 |
| Depth / Height / Width |
32 mm |
| Outer / External Diameter |
89.66 mm |
| Internal Shaft Insert / Hub Diameter |
22.32 mm |
| Net Weight |
149 g |
Package Contents
- 1 × Outboard Water Pump Impeller
Installation Guide
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Disconnect the spark plug wires to prevent accidental engine start during installation.
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Remove the lower unit from the outboard motor following your engine's service manual.
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Locate and access the water pump housing by removing the necessary bolts and covers.
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Remove the old impeller from the pump housing, noting the direction of the blade orientation.
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Clean the pump housing thoroughly, removing any debris, old gasket material, or corrosion.
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Lubricate the new impeller with a water-resistant marine grease or glycerin before installation.
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Install the new impeller into the housing with blades oriented in the correct rotation direction.
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Replace the pump housing gaskets and seals with new components to ensure proper sealing.
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Reassemble the water pump housing, securing all bolts to the manufacturer's torque specifications.
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Reinstall the lower unit onto the outboard motor, ensuring proper alignment and secure fastening.
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Reconnect the spark plug wires and perform a water pump function test.
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Run the engine in water and verify that water flows properly from the tell-tale indicator.
Troubleshooting & FAQ
Q: How do I confirm this impeller fits my Evinrude Johnson engine?
A: Check the Compatible Engine Models table above to match your engine's horsepower and model year (1973-1978 for V4/V6/V8 models from 85HP to 235HP). You can also verify by cross-referencing the OEM part numbers 389642 or 777212 with your engine's parts diagram.
Q: How often should I replace my water pump impeller?
A: It's recommended to replace your impeller every 2-3 years or every 200-300 hours of operation, whichever comes first. If you notice overheating, reduced water flow from the tell-tale, or run the engine dry even briefly, inspect and replace the impeller immediately.
Q: What are the signs that my impeller is failing?
A: Common symptoms include engine overheating, weak or no water flow from the tell-tale indicator, steam from the engine, reduced performance, and the high-temperature warning alarm activating. Inspect your impeller if you experience any of these issues.
Q: What's the difference between this aftermarket impeller and the OEM version?
A: This aftermarket impeller is manufactured to meet OEM specifications with the same dimensions (6 blades, 89.66mm outer diameter, 22.32mm hub diameter, 32mm height) and comparable materials. It offers reliable performance at a more competitive price point than OEM parts.
Q: Can I install this impeller myself or do I need a professional?
A: While experienced boaters with mechanical skills can replace an impeller following the service manual, professional installation is recommended if you're unfamiliar with lower unit removal and reassembly. Proper installation is critical for cooling system performance and engine safety.
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.