Raw Water Pump Impeller – Fits Yanmar 2GM, 3GM, 2GM20F, 3GM30F Series
This raw water pump impeller is a direct replacement for a wide range of Yanmar marine engines and Kohler marine generators. It is designed to fit Yanmar 2GM, 3GM, 2GM20F, and 3GM30F series engines, among others, manufactured between 1980 and 2005.
It directly replaces Yanmar part numbers 128296-42070, 124223-42091, 124223-42092, and others, along with multiple aftermarket equivalents from brands like Jabsco, Johnson, Kohler, and Sierra.
- Installation Method: Direct replacement
- Connection Type: Key drive
- Includes impeller and, in the JMP kit, a gasket and lubricant.
Part Number Cross-Reference
Use this table to confirm equivalent part numbers across OEM and aftermarket brands.
| 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 |
Compatible Engine Models
Confirm your engine model/year in the table below.
Yanmar Marine Engines
| 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 Marine Generators
| Brand |
Model |
OEM Part No. |
Notes |
| 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 Specifications
| Specification |
Value |
| 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) |
Package Contents
- 1 × Flexible Impeller (Replaces 124223-42091, 128296-42070, 124223-42092)
- 1 × Gasket (GAK0031) (Included with JMP kit only)
- 1 × Lubricant (Included with JMP kit only)
Installation Guide
-
Safety First: Close the seacock and ensure the engine is off and cool. Place an absorbent pad under the pump to catch any spillage.
-
Access the Pump: Locate the raw water pump. Remove the screws holding the pump cover plate in place.
-
Remove the Old Impeller: Carefully pry off the cover plate. Use impeller pullers or two screwdrivers to gently lever the old impeller out of the housing. Note the direction the blades are bent.
-
Clean and Inspect: Clean the inside of the pump housing and the cover plate. Check for scoring, cracks, or wear. Replace the pump if significant wear is found.
-
Install the New Impeller: Lubricate the inside of the housing and the new impeller with the provided lubricant or a bit of dish soap. Insert the new impeller, bending the blades in the same direction as the old one.
-
Reassemble and Test: Install the new gasket, replace the cover plate, and tighten the screws. Re-open the seacock, start the engine, and check for leaks and proper water flow.
Troubleshooting & FAQ
Q: How do I confirm this impeller fits my Yanmar engine?
A: Check your engine model and year against the compatibility table. This impeller fits many GM and HM series engines but specifically excludes European-made Yanmar models from 1997 and later. Always verify by cross-referencing your existing part number with those listed on our page.
Q: My Yanmar is a 1998 European model. Will this fit?
A: No. Based on available data, this impeller will not fit Yanmar engines made in Europe from 1997 onwards. You will need to find an alternative part for those models.
Q: How often should I replace my raw water pump impeller?
A: For optimal engine protection, we recommend inspecting your impeller annually and replacing it every 1-2 years, depending on usage hours and water conditions (e.g., sandy or silty water may require more frequent changes).
Q: What are the signs of a failing impeller?
A: Common signs include engine overheating, reduced water flow from the exhaust, visible cracks or missing blades on the impeller, or a stiff and brittle feel to the rubber.
Q: OEM vs. Aftermarket?
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?
-
Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
-
Fast Global Shipping: Free delivery worldwide in 5–15 days.
-
Direct from Manufacturer: Competitive pricing without compromising quality.