Impeller Pump Cover O-Ring – Fits Yanmar 3JH/4JH/6LP Series Engines (Replaces 119773-42570)
Impeller Pump Cover O-Ring – Fits Yanmar 3JH/4JH/6LP Series Engines (Replaces 119773-42570) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Impeller Pump Cover O-Ring – Fits Yanmar 3JH/4JH/6LP Series Engines...
Product Details
This aftermarket Impeller Pump Cover O-Ring is designed to fit a wide range of Yanmar 3JH, 4JH, and 6LP series diesel marine engines, from 39 to 315 HP, manufactured between 1990 and the present day. It ensures a proper seal for the sea water pump cover, preventing leaks and maintaining cooling system efficiency.
This part is a direct replacement for Yanmar part numbers 119773-42570 and its superseded predecessor, X0506590-01.
- Engineered for manual installation in the sea water pump cover.
- Designed to be used with Impeller Pump Cover 129670-42520.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Superseded By |
|---|---|---|
| Yanmar | X0506590-01 | 119773-42570 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Yanmar Marine Engines, please ensure your model is listed. This part is critical for maintaining the integrity of the raw water cooling circuit.
| Brand | Model | Rated HP | Stroke | OEM Part No. |
|---|---|---|---|---|
| Yanmar | 3JH3E | 40 | 4-Stroke | 119773-42570 |
| Yanmar | 3JH4E | 39 | 4-Stroke | 119773-42570 |
| Yanmar | 3JH5E | 39 | 4-Stroke | 119773-42570 |
| Yanmar | 3JH40-CR | 40 | 4-Stroke | 119773-42570 |
| Yanmar | 4JH3E EU | 56 | 4-Stroke | 119773-42570 |
| Yanmar | 4JH3TE | 75 | 4-Stroke | 119773-42570 |
| Yanmar | 4JH3HTE | 100 | 4-Stroke | 119773-42570 |
| Yanmar | 4JH3DTE | 125 | 4-Stroke | 119773-42570 |
| Yanmar | 4JH4E | 54 | 4-Stroke | 119773-42570 |
| Yanmar | 4JH4AE | 54 | 4-Stroke | 119773-42570 |
| Yanmar | 4JH4TE | 75 | 4-Stroke | 119773-42570 |
| Yanmar | 4JH4HTE | 110 | 4-Stroke | 119773-42570 |
| Yanmar | 4JH5E | 54 | 4-Stroke | 119773-42570 |
| Yanmar | 4JH45-CR | 45 | 4-Stroke | 119773-42570 |
| Yanmar | 4JH57-CR | 57 | 4-Stroke | 119773-42570 |
| Yanmar | 4JH80-CR | 80 | 4-Stroke | 119773-42570 |
| Yanmar | 4JH110-CR | 110 | 4-Stroke | 119773-42570 |
| Yanmar | 6LP-DTE | 250 | 4-Stroke | 119773-42570 |
| Yanmar | 6LP-STE | 300 | 4-Stroke | 119773-42570 |
| Yanmar | 6LPA-DTE | 250 | 4-Stroke | 119773-42570 |
| Yanmar | 6LPA-DTP | 260 | 4-Stroke | 119773-42570 |
| Yanmar | 6LPA-STE | 300 | 4-Stroke | 119773-42570 |
| Yanmar | 6LPA-STP | 315 | 4-Stroke | 119773-42570 |
| Yanmar | 6LPA-STP2 | 315 | 4-Stroke | 119773-42570 |
Technical Specs
- Product Type
- Pump Cover O-Ring
- Installation
- Manual installation in sea water pump cover
- Housing Material
- Rubber/Elastomer
- Housing Color
- Black
- Dimensions
- 6.5" L x 6.5" W x 0.1" H
- Fitting Type
- O-Ring
- Other Technical Attributes
- Used with Impeller Pump Cover 129670-42520
What’s in the Box
- 1 x O-Ring (119773-42570/X0506590-01)
Installation Notes
- Turn off the engine and close the raw water intake seacock.
- Loosen and remove the screws or bolts securing the sea water pump cover plate.
- Carefully pry off the cover plate. The old o-ring should be seated in a groove on the plate or the pump housing.
- Remove the old o-ring and thoroughly clean the groove and mating surfaces, ensuring they are free of salt, debris, and corrosion.
- Seat the new o-ring into the groove. A light application of silicone grease can help hold it in place.
- Reinstall the pump cover, making sure it is aligned correctly.
- Tighten the cover screws in a crisscross pattern to apply even pressure. Do not overtighten.
- Open the seacock, start the engine, and immediately check the pump cover for any signs of water leakage.
Troubleshooting & FAQ
How do I know if this o-ring will fit my engine?
This o-ring is specifically designed for Yanmar 3JH, 4JH, and 6LP series engines. To ensure a perfect match, please compare your engine model and year to the detailed compatibility table on this page. Verifying the part number 119773-42570 against your service manual is also recommended.
What are the signs of a failing pump cover o-ring?
The most common sign of a worn or damaged o-ring is a water leak or steady drip from the seam of the sea water pump cover, which may be more noticeable when the engine is running. A compromised seal can lead to cooling inefficiency and potential water damage to surrounding components.
How often should this o-ring be replaced?
It is standard practice to replace the pump cover o-ring whenever you replace the flexible impeller. This preventative maintenance ensures a reliable, leak-free seal and is a low-cost way to protect your engine's cooling system.
Is any sealant required during installation?
No, this o-ring is designed to create a seal on its own. The use of additional liquid sealant is not recommended as it can interfere with the seal or contaminate the cooling system. Ensure the mating surfaces are clean, dry, and smooth before installation.
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.
Payment & Security
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