Thermostat Gasket – Fits Yanmar 6LY Series Marine Diesel Engines (Replaces 119593-49291)
Thermostat Gasket – Fits Yanmar 6LY Series Marine Diesel Engines (Replaces 119593-49291) 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
Thermostat Gasket – Fits Yanmar 6LY Series Marine Diesel Engines (R...
Product Details
This replacement Thermostat Gasket ensures a reliable, leak-free seal for the cooling system on Yanmar 6LY Series marine diesel engines. It is designed for 6-cylinder, 315–440 HP, 4-stroke models produced between 1992 and 1996.
It serves as a direct replacement for Yanmar part number 119593-49291.
- Installs between the thermostat and its housing to create a secure seal.
- Engineered from heat-resistant composite materials for durability in marine environments.
- Package includes one gasket for a complete installation.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Yanmar | 119593-49291 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Yanmar engines, this part is documented for the 6LY series. Please verify your specific model is listed.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Yanmar | 6LY-UTE | 315 | 4-Stroke | 1992–1996 | 119593-49291 | Used with thermostat 119593-49550 |
| Yanmar | 6LY Series | 315-440 | 4-Stroke | 1992–1996 | 119593-49291 |
Technical Specs
- Product Type
- Thermostat Gasket
- Installation
- Positioned between thermostat and housing
- Fuel Type
- Diesel
- Housing Material
- Heat-resistant composite
- Dimensions
- 9.5" x 9.5" x 0.1"
- Operating Temperature
- Rated for high-temperature cooling system operation
- Warranty
- 6 months
- Other Technical Attributes
- Designed for 6LY Series marine engines
What’s in the Box
- 1 x Thermostat Gasket (119593-49291)
Installation Notes
- Disconnect the battery and ensure the engine has completely cooled.
- Drain the engine coolant to a level below the thermostat housing.
- Carefully remove the bolts securing the thermostat housing cover.
- Remove the old housing, thermostat, and gasket. Note the thermostat's orientation.
- Thoroughly clean any old gasket material from both the housing and engine mating surfaces.
- Install the new thermostat in the correct orientation, followed by the new gasket.
- Re-secure the housing cover, tightening bolts to the manufacturer-specified torque.
- Refill the cooling system with the appropriate coolant.
- Reconnect the battery, start the engine, and carefully inspect for any leaks as it reaches operating temperature.
Troubleshooting & FAQ
How do I know if this gasket fits my Yanmar engine?
This gasket is specifically for the Yanmar 6LY Series (315-440 HP) manufactured between 1992 and 1996. Always verify your engine model and confirm the part number is 119593-49291 before ordering.
What are the signs of a failing thermostat gasket?
Common symptoms include visible coolant leaks or residue around the thermostat housing, engine overheating due to coolant loss, or an erratic engine temperature gauge.
Can I reuse my old gasket?
No. Thermostat gaskets are single-use components designed to crush and seal under pressure. Always use a new gasket when replacing a thermostat to ensure a proper, leak-free seal.
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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