Water Pump Impeller 388702 – Fits Johnson/Evinrude 20HP 25HP 28HP 30HP 35HP Outboard Motors
This high-performance water pump impeller is engineered for Johnson/Evinrude 2-stroke outboard motors rated 20HP, 25HP, 28HP, 30HP, and 35HP. Designed to deliver reliable cooling performance, this impeller ensures proper water circulation through your engine's cooling system, protecting against overheating and extending motor life.
This aftermarket replacement impeller directly replaces OEM part numbers 388702, 395289, 395265, 47-89982, and 47-65958, providing a cost-effective alternative without compromising quality or performance.
- Constructed from scientifically engineered high-performance neoprene rubber for superior durability and marine corrosion resistance
- Includes impeller with key/pin for complete installation
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6-blade design optimized for efficient water flow and cooling
Part Number Cross-Reference
Use this table to confirm equivalent part numbers across OEM and aftermarket brands.
| Brand |
Part Number |
| Johnson/Evinrude |
388702 |
| Johnson/Evinrude |
395289 |
| Johnson/Evinrude |
395265 |
| Johnson/Evinrude |
47-89982 |
| Johnson/Evinrude |
47-65958 |
| Sierra |
18-3051 |
| CEF |
500370 |
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.
| Brand |
Rated HP |
Stroke |
| Johnson/Evinrude |
20HP |
2-Stroke |
| Johnson/Evinrude |
25HP |
2-Stroke |
| Johnson/Evinrude |
28HP |
2-Stroke |
| Johnson/Evinrude |
30HP |
2-Stroke |
| Johnson/Evinrude |
35HP |
2-Stroke |
Technical Specifications
| Specification |
Value |
| Material |
High-performance neoprene rubber |
| Number of Blades |
6 |
| External Impeller Overall Diameter |
51.00 mm |
| Internal Shaft Insert Diameter |
16.00 mm |
| Item Weight |
Approximately 37 g |
Package Contents
- 1 × Outboard Rubber Impeller with Key/Pin
Installation Guide
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Disconnect the fuel line and remove the engine cowling to access the lower unit. Ensure the engine is off and cool before starting.
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Remove the water pump housing by unscrewing the mounting bolts that secure it to the lower unit gearcase.
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Extract the old impeller from the pump housing carefully, noting the direction of the blade curvature for proper installation.
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Inspect the pump housing and plate for cracks, corrosion, or wear. Replace any damaged components before continuing.
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Lubricate the new impeller blades with a marine-grade water-resistant grease or glycerin to prevent tearing during installation.
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Install the key/pin into the impeller shaft slot as indicated, ensuring it is seated properly to engage with the drive shaft.
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Insert the new impeller into the housing with blades oriented in the correct rotation direction (typically curved in the direction of shaft rotation).
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Reinstall the pump housing onto the lower unit, aligning all bolt holes and gasket surfaces carefully.
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Torque mounting bolts to manufacturer specifications in a crisscross pattern to ensure even sealing and prevent leaks.
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Reattach the engine cowling and reconnect the fuel line securely.
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Run the engine in a test tank or on muffs and confirm strong water flow from the telltale outlet. Monitor engine temperature during the first few minutes of operation.
Troubleshooting & FAQ
Q: How do I confirm this impeller fits my Johnson/Evinrude engine?
A: Cross-reference your engine's horsepower and model year with the compatibility table above. If your engine originally used OEM part numbers 388702, 395289, 395265, 47-89982, or 47-65958, this impeller is the correct replacement.
Q: How often should I replace my water pump impeller?
A: Most manufacturers recommend replacing the impeller every 2–3 years or 200–300 hours of operation, whichever comes first. If you operate in sandy, silty, or debris-heavy water, inspect and replace it more frequently.
Q: What are the signs that my impeller is failing?
A: Common symptoms include weak or no water flow from the telltale, engine overheating, steam from the engine, or reduced performance. Inspect the impeller immediately if you notice any of these signs.
Q: Can I install this impeller myself or do I need a mechanic?
A: If you have basic mechanical skills and the right tools, you can install this impeller yourself by following the installation guide. However, professional installation is recommended if you're unfamiliar with outboard motor servicing to ensure proper fit and function.
Q: What's the difference between this aftermarket impeller and the OEM version?
A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.
Q: How fast do you ship and how much does it cost?
A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.
Q: What is your warranty and return policy?
A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.
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.
Why Choose JLM MARINE?
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Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
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Fast Global Shipping: Free delivery worldwide in 5–15 days.
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Direct from Manufacturer: Competitive pricing without compromising quality.