26-830749 Lower Unit Grease Gaskets,Gearcase Lube Drain Screw Washer,6Pcs,for Mercury 115FS 150 EFI Four Stroke and Mariner Outboards and MerCruiser Stern Drives
26-830749 Lower Unit Grease Gaskets,Gearcase Lube Drain Screw Washer,6Pcs,for Mercury 115FS 150 EFI Four Stroke and Mariner Outboards and MerCruiser Stern Drives 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
26-830749 Lower Unit Grease Gaskets,Gearcase Lube Drain Screw Washe...
Product Details
This Gearcase Drain Plug Gasket ensures a tight, reliable seal for the gear lube drain and fill screws. It is designed to fit all MerCruiser stern drives and a range of Mercury/Mariner outboards, including 115FS and 150 EFI 4-Stroke models that use a 3/8-16 gearcase drain screw.
This part is a direct replacement for Mercury OEM part numbers 26-830749 and the current supersession, 8M0204693.
- Constructed from durable rubber-coated stainless steel for a leak-proof seal.
- Installation is simple: place the gasket between the drain plug and the gearcase housing before tightening.
- Each package includes ten gaskets, providing excellent value for routine maintenance.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number | Superseded By |
|---|---|---|
| Mercury | 26-830749 | 8M0204693 |
| Mercury | 8M0204693 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
Compatible with select Mercury/Mariner outboard models, including the 115FS and 150 EFI 4-Stroke, and other models equipped with 3/8-16 drain plug holes.
Fits all MerCruiser stern drive models that use a 3/8-16 gearcase drain or fill screw.
| Brand | Model | Rated HP | Stroke | OEM Part No. | Notes |
|---|---|---|---|---|---|
| Mercury | 115FS | 115 | 4-Stroke | 26-830749/8M0204693 | Current part is 8M0204693 |
| Mercury | 150 EFI | 150 | 4-Stroke | 26-830749/8M0204693 | Current part is 8M0204693 |
| Mercury | Various Models | 4-Stroke | 26-830749/8M0204693 | Fits models with 3/8-16 drain holes | |
| MerCruiser | All Models | 26-830749/8M0204693 | Fits all with 3/8-16 drain holes |
Technical Specs
- Product Type
- Gearcase Drain Plug Gasket/Washer
- Installation
- Placed between drain plug and gearcase housing
- Material
- Rubber-coated stainless steel
- Color
- Yellow
- Dimensions
- Inner diameter: 9 mm (0.35 in), Outer diameter: 14 mm (0.55 in)
- Thread Size
- Fits 3/8-16 gearcase drain/fill screw holes
What’s in the Box
- 10 x Gearcase Drain Plug Seal Washer Gaskets (26-830749/8M0204693)
Installation Notes
- Position a suitable drain pan underneath the lower unit gearcase.
- Carefully remove the gearcase drain/fill screw, allowing the oil to drain completely.
- Remove and discard the old gasket from the drain screw.
- Clean the screw threads and the sealing surface on the gearcase.
- Slide the new gasket onto the drain screw.
- Reinstall the drain screw and tighten it to the manufacturer-specified torque. Do not overtighten, as this can damage the gasket or threads.
Troubleshooting & FAQ
How do I know if this gasket fits my engine?
This gasket is designed for all MerCruiser stern drives and specific Mercury/Mariner outboards with 3/8-16 drain/fill screw holes, like the 115FS and 150 EFI 4-Stroke models. Always verify your screw size and check the compatibility list before ordering.
What is the difference between part numbers 26-830749 and 8M0204693?
The part number 8M0204693 is the current OEM version that supersedes the older 26-830749. They are functionally identical and completely interchangeable. This listing replaces both.
How often should I replace my gearcase drain gasket?
It is best practice to use a new gasket every time you change your gearcase oil. This ensures a fresh, perfect seal and prevents leaks or water intrusion.
What signs indicate a failing drain plug gasket?
Common signs of a bad gasket include visible gear oil leaking from around the drain plug, discovering milky or watery gear oil during a change (indicating water intrusion), or seeing visible cracks, brittleness, or deformation on the old gasket upon removal.
Is this gasket made of just rubber or is it metal?
This is a composite gasket, constructed from rubber-coated stainless steel. This design combines the strength and rigidity of a metal washer with the superior sealing properties of rubber for a durable, leak-free fit.
Can I reuse my old gasket?
Reusing an old gasket is not recommended. Gaskets are designed to compress and create a one-time seal. Reusing one can lead to an improper fit, causing gear oil leaks or, worse, water entering your gearcase, which can lead to catastrophic failure.
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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