Water Pump Impeller Kit – Fits Kohler Marine Generators 4–7.3 HP (Replaces Kohler 359978)
Water Pump Impeller Kit – Fits Kohler Marine Generators 4–7.3 HP (Replaces Kohler 359978) is backordered and will ship as soon as it is back in stock.
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Water Pump Impeller Kit – Fits Kohler Marine Generators 4–7.3 HP (R...
Water Pump Impeller Kit – Fits Kohler Marine Generators 4–7.3 HP (Replaces Kohler 359978) is backordered and will ship as soon as it is back in stock.
Product Details
This water pump impeller kit is an aftermarket replacement for the seawater pump used on selected Kohler marine generators. Catalog information identifies the application as the Kohler GM28487 pump and lists Kohler 359978 as the replacement reference. The catalog describes the supplied service item as the impeller itself; no pump housing or complete water pump is included.
Use the fitment information below to confirm that your generator model and pump match before ordering. Model names, horsepower ratings, and pump applications must be considered together.
- For selected Kohler marine generator models 4EF, 5E, 6EF, 7.3E, 4EFCD, 5ECD, 6EFCD, and 7.3ECD.
- Application: Kohler GM28487 seawater pump.
- Service replacement for a worn, cracked, brittle, or damaged impeller.
- Aftermarket replacement part; verify the original impeller and pump configuration before installation.
Part Number References
The following manufacturer reference is provided for identification and cross-checking only. It does not mean that the replacement is manufactured by Kohler.
| Brand | Part Number | Reference Type |
|---|---|---|
| Kohler | 359978 | Replacement reference |
Engine & Model Compatibility
Catalog fitment identifies this impeller kit for the Kohler GM28487 pump on the following generator models. Confirm the pump identification and compare the original part before purchase.
| Brand | Model | Rated HP | Stroke | Pump | Replacement Reference |
|---|---|---|---|---|---|
| Kohler | 4EF | 4 | Not specified | GM28487 | 359978 |
| Kohler | 5E | 5 | Not specified | GM28487 | 359978 |
| Kohler | 6EF | 6 | Not specified | GM28487 | 359978 |
| Kohler | 7.3E | 7.3 | Not specified | GM28487 | 359978 |
| Kohler | 4EFCD | 4 | Not specified | GM28487 | 359978 |
| Kohler | 5ECD | 5 | Not specified | GM28487 | 359978 |
| Kohler | 6EFCD | 6 | Not specified | GM28487 | 359978 |
| Kohler | 7.3ECD | 7.3 | Not specified | GM28487 | 359978 |
Important: The catalog evidence reviewed for this product establishes Kohler GM28487 applications. Onan, Sherwood pump-model, and other generator fitments are not included here because they were not confirmed for this specific application.
Technical Specifications
- Product Type
- Water pump impeller kit; impeller service replacement
- Application
- Kohler GM28487 seawater pump
- Replacement Reference
- Kohler 359978
- Fitment
- Selected Kohler 4EF, 5E, 6EF, 7.3E, 4EFCD, 5ECD, 6EFCD, and 7.3ECD marine generators
- Construction
- Confirm material, hub design, blade count, dimensions, and drive configuration against the original impeller before installation.
- Included Pump Hardware
- No pump housing, cover plate, shaft, or complete pump assembly is included.
What’s in the Box
- 1 x Water pump impeller
The catalog identifies the replacement as an impeller-only service item. A gasket, O-ring, key, cover plate, or other installation hardware is not confirmed as included.
Installation Notes
- Shut down the generator, disconnect the power source, and close the appropriate seawater inlet or seacock.
- Place a suitable collection pan beneath the pump to catch residual water.
- Remove the pump cover plate according to the generator or pump service instructions.
- Before removing the old impeller, note the direction in which its blades are bent.
- Remove the old impeller using an appropriate impeller puller or suitable removal method. Avoid damaging the pump housing or shaft.
- Inspect the pump housing, cover plate, shaft, seal surfaces, and drive interface for wear or damage.
- Lubricate the new impeller with a lubricant approved for the pump manufacturer and impeller material. Do not run the pump dry.
- Install the impeller with the blades oriented in the same direction as the removed impeller and reinstall the cover plate using the correct sealing method for the pump.
- Open the seacock, restore power, start the generator, and immediately check seawater flow and the pump area for leaks.
Troubleshooting & FAQ
How do I know if this impeller will fit my generator?
Confirm that your generator is one of the listed Kohler models and that it uses the GM28487 seawater pump. Also compare the old impeller, drive interface, and pump cover configuration before ordering. Horsepower alone is not sufficient to establish fitment.
What are the signs of a worn impeller?
Common symptoms include reduced seawater flow, higher-than-normal operating temperature, an overheating alarm, or little to no water discharge. Inspect for cracked, hardened, distorted, or missing blades.
How often should the impeller be inspected?
Inspect the impeller during scheduled maintenance and whenever cooling-water flow decreases. Replacement timing depends on operating hours, storage conditions, water quality, and manufacturer recommendations. Saltwater exposure and extended periods without operation can accelerate deterioration.
Is this an OEM part?
No. This is an aftermarket replacement. The Kohler number shown on this page is a manufacturer reference used for identification and compatibility checking.
Does the package include an O-ring or gasket?
No additional seal or installation hardware is confirmed for this listing. The documented package is one impeller, so obtain any required gasket or O-ring separately if the pump service procedure calls for one.
Safety & Important Information
- Verify the generator model, pump number, original impeller, and drive configuration before purchase.
- Do not operate the seawater pump dry; dry running can damage the impeller and pump.
- Inspect the pump housing and cover plate whenever the impeller is replaced.
- This is an aftermarket impeller replacement, not an OEM Kohler component.
- Follow the generator and pump manufacturer’s service instructions. Professional installation is recommended when the correct procedure is uncertain.
About Sea Sierra
- Marine Replacement Parts — Replacement components for routine marine maintenance and repair.
- Application-Focused Listings — Product references and fitment information are provided to help you compare the original part and pump configuration.
- Global Fulfillment — Shipping options and delivery estimates are shown during checkout based on destination and availability.
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