Raw Water Pump Impeller – Fits Yanmar 2GM, 3GM Series (Replaces 128296-42070, 124223-42091)
Raw Water Pump Impeller – Fits Yanmar 2GM, 3GM Series (Replaces 128296-42070, 124223-42091) is backordered and will ship as soon as it is back in stock.
Worry-free returns
Worry-free returns
Shop with confidence. If you’re not completely satisfied, eligible items may be returned within the return window, provided they are unused and in original packaging.
If the return is due to our error or a defective item, we’ll make it right.
Please contact us before returning any item.
Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
International delivery times may vary due to customs processing.
Tracking information will be provided once your order ships.
Raw Water Pump Impeller – Fits Yanmar 2GM, 3GM Series (Replaces 128...
Raw Water Pump Impeller – Fits Yanmar 2GM, 3GM Series (Replaces 128296-42070, 124223-42091) is backordered and will ship as soon as it is back in stock.
Product Details
This is a direct replacement Raw Water Pump Impeller – Fits Yanmar 2GM, 3GM, 2GM20F, 3GM30F Series (Replaces 128296-42070, 124223-42091), engineered for reliable performance in various Yanmar marine engines and Kohler marine generators. It's designed for Yanmar models including the 2GM, 3GM, 2GM20F, 3GM30F, 2QM, 3QM, and 3HM series, as well as Kohler generator models 8E, 10E, 12.5E, and 12.5CF (SN 296898 and below).
This impeller serves as an aftermarket equivalent for numerous part numbers, including Yanmar 128296-42070 and 124223-42091, Jabsco 22799-0001, Johnson 09-824P-9, and Kohler 250872.
- Installs as a direct replacement for compatible models.
- Features a durable key drive insert for secure shaft engagement.
- JMP kits include a gasket and lubricant for a complete installation.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yanmar | 128296-42070 |
| Yanmar | 124223-42091 |
| Yanmar | 124223-42092 |
| Yanmar | 124223-42090 |
| Yanmar | 128296-42040 |
| Jabsco | 22799-0001 |
| Johnson | 09-824P-9 |
| Johnson | 09-827 |
| Johnson | 09-827B |
| Kohler | 250872 |
| Kohler | 229955 |
| Kohler | 229955KIT |
| Kohler | 252475 |
| Sierra | 18-8950 |
| Sierra | 23-2003 |
| Sierra | 23-3304 |
| CEF | 500129 |
| CEF | 500238 |
| VETUS | IMP00101 |
| ANCOR | J050016 |
| JMP | 7052-01 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Yanmar engines, note that this impeller will not fit European-made models manufactured in 1997 or later.
For Kohler generators, compatibility is limited to units with a serial number of 296898 and below.
| Brand | Model | Rated HP | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|
| Yanmar | 2GM, 2GMF | 1980–1983 | 124223-42091 | ||
| Yanmar | 3GM, 3GMF, 3GMDF | 1980–1983 | 124223-42091 | ||
| Yanmar | 2GM20F, 2GM20FVE | 20 | 1983–2005 | 124223-42091 | Will not fit 1997 and later European made models |
| Yanmar | 3GM30F, 3GM30FVE | 30 | 1983–2005 | 124223-42091 | Will not fit 1997 and later European made models |
| Yanmar | 2QM, 2QM20 | 128296-42070 | |||
| Yanmar | 3QM, 3QM30 | 128296-42070 | |||
| Yanmar | 3HM, 3HMF | 1980–1983 | 128296-42070 | ||
| Yanmar | 3HM35, 3HM35F, 3HM35C | 1983–1992 | 128296-42070 | ||
| Kohler | 8E | 250872/229955 | SN 296898 and below | ||
| Kohler | 10E | 250872/229955 | SN 296898 and below | ||
| Kohler | 12.5E | 250872/229955 | SN 296898 and below | ||
| Kohler | 12.5CF | 250872/229955 | SN 296898 and below |
Technical Specs
- Product Type
- Marine Raw Water Pump Impeller
- Installation
- Direct replacement
- Connection
- Key drive
- Dimensions
- 51 mm diameter × 22 mm width (2" × 7/8")
- Shaft Diameter
- 12.7 mm
- Number of Blades
- 6
- Insert Type
- Key drive
- Key Width
- 5.25 mm (approximate)
- Insert Material
- Brass (JMP version)
- Impeller Material
- Neoprene or Nitrile (varies by brand)
- Weight
- 0.15 lbs (0.068 kg)
- Warranty
- 1-2 years (varies by manufacturer)
What’s in the Box
- 1 × Flexible Impeller (Replaces Yanmar 124223-42091/128296-42070/124223-42092)
- 1 × Gasket (GAK0031) (JMP kit only)
- 1 × Lubricant (JMP kit only)
Installation Notes
- Close the raw water seacock to prevent water from entering the vessel.
- Access the raw water pump housing and remove the cover plate screws.
- Carefully remove the old impeller. Use impeller pullers or two screwdrivers to gently pry it out. Avoid scoring the housing.
- Clean the inside of the pump housing, removing any old debris or impeller fragments.
- Apply a small amount of the supplied lubricant to the inside of the housing and to the new impeller.
- Insert the new impeller, bending the blades in the correct direction of the pump's rotation.
- Install the new gasket (if included) and replace the pump cover plate, tightening the screws evenly.
- Open the raw water seacock.
- Start the engine and immediately check the pump and exhaust for proper water flow and for any leaks.
Troubleshooting & FAQ
How do I confirm this impeller fits my engine?
The best way is to cross-reference your existing impeller's part number with the numbers in our Part Number Matrix. Also, verify your engine model and year falls within the ranges listed in the compatibility table. Be aware this part does not fit Yanmar models made in Europe from 1997 onwards.
What are the signs of a failing water pump impeller?
Common symptoms include the engine running hotter than normal, a complete overheating alarm, or a noticeable reduction in water flow from the exhaust outlet. A visual inspection may reveal cracked, brittle, or missing blades.
How often should I replace my impeller?
As a preventative maintenance item, most marine mechanics and engine manufacturers recommend replacing the raw water pump impeller annually or every 200-300 hours of use, whichever comes first. Always consult your engine's service manual for specific intervals.
What's the difference between Neoprene and Nitrile impellers?
Neoprene is the most common material and is suitable for most raw water cooling applications where only trace amounts of oil are present. Nitrile impellers offer superior resistance to oil, fuel, and chemicals, making them ideal for bilge pumps or in engine cooling systems where contamination is a risk.
Does this kit include a gasket and lubricant?
The package contents vary by brand. The JMP branded kits include one impeller, one gasket, and a packet of lubricant. For other brands, please check the "What's in the Box" section for specific inclusions.
Is this an OEM part or aftermarket?
This listing is for an aftermarket replacement part, not an original equipment manufacturer (OEM) component. It has been engineered to meet or exceed OEM specifications using comparable materials and is manufactured in an ISO 9002 certified facility with batch inspections for quality assurance.
What are the shipping speed and cost?
We ship worldwide quickly, with typical transit times of 5–15 days for most regions. Standard shipping is free. Expedited shipping options, if available for your location, will be presented at checkout.
What is the warranty and return policy?
This product is covered by a 1-year warranty against manufacturing defects under normal marine use. If you encounter an issue, please contact our support team with your order details. Returns are accepted within our standard window for items that are unused and in their original condition. See our full policy page or contact us for instructions.
Safety & Important Info
- Verify images/specifications vs 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.
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
