O-Ring – Fits Yanmar Marine Diesel Engines (Replaces 119574-42570)
O-Ring – Fits Yanmar Marine Diesel Engines (Replaces 119574-42570) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
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O-Ring – Fits Yanmar Marine Diesel Engines (Replaces 119574-42570)
Product Details
This OEM-style O-Ring – Fits Yanmar Marine Diesel Engines provides a reliable seal for cooling system applications. It is compatible with multiple Yanmar marine diesel engine series and is primarily used in sea water pump assemblies, particularly on 6LY series engines.
This part is a direct replacement for Yanmar OEM part number 119574-42570.
- Provides a crucial seal for the sea water cooling pump.
- Engineered to meet OEM specifications for fit and function.
- Designed for use in marine saltwater environments.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yanmar | 119574-42570 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
Compatible with the following Yanmar marine diesel engines.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yanmar | 6LY2-STE | 4-Stroke | 119574-42570 | For cooling sea water pump | ||
| Yanmar | 6LY2-ST | 4-Stroke | 119574-42570 | For cooling sea water pump | ||
| Yanmar | 6LY2-STVY | 4-Stroke | 119574-42570 | For cooling sea water pump | ||
| Yanmar | 6LY2-WDT | 4-Stroke | 119574-42570 | For cooling sea water pump | ||
| Yanmar | 6LY2-WDTZY | 4-Stroke | 119574-42570 | For cooling sea water pump | ||
| Yanmar | 6LY2-WST | 4-Stroke | 119574-42570 | For cooling sea water pump | ||
| Yanmar | 6LY2A-STP | 4-Stroke | 119574-42570 | For cooling sea water pump | ||
| Yanmar | 6LY2A-UTP | 4-Stroke | 119574-42570 | For cooling sea water pump | ||
| Yanmar | 6LY2M-WDT | 4-Stroke | 119574-42570 | For cooling pump (sea water) | ||
| Yanmar | 6LY2M-WST | 4-Stroke | 119574-42570 | For cooling pump (sea water) | ||
| Yanmar | 6LYA-STE | 4-Stroke | 119574-42570 | For cooling sea water pump | ||
| Yanmar | 6LYA-STE(P) | 4-Stroke | 119574-42570 | For cooling sea water pump | ||
| Yanmar | 6LYA-STP | 4-Stroke | 119574-42570 | For cooling sea water pump | ||
| Yanmar | 6LYA-UTE | 4-Stroke | 119574-42570 | For cooling sea water pump | ||
| Yanmar | 6LYA-UTE(P) | 4-Stroke | 119574-42570 | For cooling sea water pump | ||
| Yanmar | 6LY400 | 4-Stroke | 119574-42570 | For cooling pump (sea water) | ||
| Yanmar | 6LY400CN | 4-Stroke | 119574-42570 | For cooling pump (sea water) | ||
| Yanmar | 6LY440 | 4-Stroke | 119574-42570 | For cooling pump (sea water) | ||
| Yanmar | 6LY440CN | 4-Stroke | 119574-42570 | For cooling pump (sea water) |
Technical Specs
- Product Type
- O-Ring Gasket
- Application
- Sea Water Cooling Pump
- Dimensions
- 7.0" L x 7.0" W x 0.1" H
- OEM Part Number
- 119574-42570
What’s in the Box
- 1 x O-Ring (119574-42570)
Installation Notes
- Ensure the engine is off and the sea cock is closed before beginning installation.
- Remove the screws from the sea water pump's end cover plate.
- Carefully pry off the end cover and remove the old O-ring, noting its exact position.
- Thoroughly clean the groove where the O-ring sits and the mating surface of the end cover.
- Apply a light coat of waterproof grease or soap to the new O-ring to aid sealing.
- Seat the new O-ring firmly and evenly into its groove.
- Reattach the end cover, ensuring it is aligned correctly, and tighten the screws in a star pattern.
- Once secure, open the sea cock, start the engine, and immediately check for any leaks around the pump housing.
Troubleshooting & FAQ
How do I know if this o-ring fits my engine?
This o-ring is designed for many Yanmar 6LY series engines. The most reliable method is to confirm the part number 119574-42570 is listed in your engine's service manual. You can also use the compatibility table on this page to check your specific model.
What are the signs of a failing sea water pump o-ring?
Common signs include visible water leaks or drips from the sea water pump housing, particularly around the end cover. An unexplained loss of cooling performance or engine overheating can also indicate a seal failure.
How often should this o-ring be replaced?
For preventative maintenance, it is best practice to replace the sea water pump o-ring whenever you replace the pump's impeller, typically as part of your annual service schedule.
Is this an impeller o-ring or an end cover o-ring?
This part is often referred to by both names depending on the retailer. It is the o-ring that creates a seal for the end cover of the sea water pump, inside which the impeller is housed.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.
Shipping speed & cost
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
Warranty & returns
Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out 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.
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