Water Pump Gasket – Fits Yamaha 6HP & 8HP Outboards (Replaces 6G1-44315-A0-00)
Water Pump Gasket – Fits Yamaha 6HP & 8HP Outboards (Replaces 6G1-44315-A0-00) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
Worry-free returns
You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.
Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Product Details
This Water Pump Gasket – Fits Yamaha 6HP & 8HP Outboards provides a reliable seal for the water pump housing. It is designed for various Yamaha 2-stroke models from 1984 to 2009 and select 4-stroke models up to 2009, ensuring proper cooling system function.
It serves as a direct interchange for Yamaha part numbers 6G1-44315-A0-00 and 6G1-44315-00-00, as well as Sierra 18-0753 and Mariner 27-11591 / 11591M.
- Engineered as a direct replacement for the OEM gasket.
- Seals the connection between the water pump housing and lower unit components.
- Crafted from durable green gasket material for a secure fit.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Notes |
|---|---|---|
| Yamaha | 6G1-44315-A0-00 | Current OEM Part Number |
| Yamaha | 6G1-44315-00-00 | Superseded by 6G1-44315-A0-00 |
| Mariner | 27-11591 | Aftermarket Replacement |
| Mariner | 11591M | Aftermarket Replacement |
| Sierra | 18-0753 | Aftermarket Replacement |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Yamaha applications, this gasket fits specific 6HP and 8HP two-stroke models manufactured between 1984 and 2009. Please verify your model code and year.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. |
|---|---|---|---|---|---|
| Yamaha | 6C/MSH/CMH/CWH | 6 | 2-Stroke | 1986–1999 | 6G1-44315-A0-00 |
| Yamaha | 6MBK'07/D/DMH/DWH | 6 | 2-Stroke | 1986–2000 | 6G1-44315-A0-00 |
| Yamaha | 8C/MSH/MH/CMH/CWH | 8 | 2-Stroke | 1984–2009 | 6G1-44315-A0-00 |
For Mariner applications, this part serves as a replacement for part numbers 27-11591 and 11591M, typically used on 6HP and 8HP 2-stroke outboards. Complete year ranges are unverified, so please confirm fitment by part number.
| Brand | Model | Rated HP | Stroke | OEM Part No. |
|---|---|---|---|---|
| Mariner | Various | 6 | 2-Stroke | 27-11591, 11591M |
| Mariner | Various | 8 | 2-Stroke | 27-11591, 11591M |
Technical Specs
- Product Type
- Water Pump Gasket
- Installation
- Direct replacement for OEM gasket
- Material
- Green gasket material
- Position
- Between water pump housing and lower unit components
- Dimensions
- 4.0 in x 5.13 in x 0.13 in
- OEM Number
- 6G1-44315-A0-00
- Supersedes
- 6G1-44315-00-00
What’s in the Box
- 1 x Gasket, Water Pump (6G1-44315-A0-00)
Installation Notes
- Disconnect the battery and remove the engine cover. Ensure the engine is in neutral.
- Drain the gearcase lubricant from the lower unit.
- Remove the bolts securing the lower unit to the upper casing and carefully lower it.
- Unbolt and remove the water pump housing to access the old gasket.
- Clean both mounting surfaces thoroughly, removing all old gasket material and corrosion.
- Place the new gasket in position, ensuring it aligns with all bolt holes and water passages.
- Reinstall the water pump housing and torque the bolts to the manufacturer's specification.
- Reattach the lower unit to the engine, ensuring the driveshaft, shift shaft, and water tube are correctly aligned. Secure with bolts.
- Refill the gearcase with fresh lubricant before operating.
Troubleshooting & FAQ
How do I know if this gasket fits my engine?
The best way to confirm fitment is to check your OEM part number. This gasket replaces Yamaha 6G1-44315-A0-00 and 6G1-44315-00-00. You can also review the compatibility tables on this page for specific Yamaha and Mariner models, but always prioritize the part number.
What are the signs of a failing water pump gasket?
Common symptoms include the engine overheating, a weak or inconsistent water stream from the "telltale" outlet, or visible water leaking from the seam between the lower unit and the gearcase housing. An overheating alarm during operation is a critical indicator.
Is it necessary to replace the whole impeller kit or just the gasket?
While you can replace just the gasket if it is the only failed component, it is highly recommended to replace the entire water pump kit (impeller, gaskets, wear plate, etc.) at the same time. The parts wear together, and replacing only the gasket is often a temporary fix.
What's the difference between OEM part 6G1-44315-A0-00 and 6G1-44315-00-00?
The part number 6G1-44315-A0-00 is a direct supersession for 6G1-44315-00-00. This typically means the manufacturer made a minor update to the material or design for improved performance or manufacturing efficiency. They are functionally identical and fully interchangeable.
Can I reuse my old water pump gasket?
No. Gaskets are designed for one-time use. They create a seal by compressing into imperfections on the mating surfaces. Once removed, they lose their ability to create a reliable, leak-proof seal and must be replaced.
Why does the gasket material matter?
The gasket material is chosen for its ability to resist corrosion from saltwater and freshwater, withstand the heat generated by the engine, and maintain a flexible seal under pressure. Using a gasket made of the correct material is critical for the longevity of your cooling system.
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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