Gearcase Drain Screw Gasket Washer – Mercury Marine Replacement for 26-830749
Gearcase Drain Screw Gasket Washer – Mercury Marine Replacement for 26-830749 is backordered and will ship as soon as it is back in stock.
Worry-free returns
Worry-free returns
Shop with confidence. If you’re not completely satisfied, eligible items may be returned within the return window, provided they are unused and in original packaging.
If the return is due to our error or a defective item, we’ll make it right.
Please contact us before returning any item.
Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
International delivery times may vary due to customs processing.
Tracking information will be provided once your order ships.
Gearcase Drain Screw Gasket Washer – Mercury Marine Replacement for...
Gearcase Drain Screw Gasket Washer – Mercury Marine Replacement for 26-830749 is backordered and will ship as soon as it is back in stock.
Product Details
This gearcase drain screw gasket washer is a replacement sealing washer for compatible Mercury Marine gearcase drain screws. It helps seal the drain or fill screw during lower-unit service and helps reduce the risk of gear-lubricant leakage or water entry when correctly matched to the application.
The washer replaces Mercury Marine OEM reference 26-830749. Catalog references also identify Sierra drain screw gasket applications 18-2430 and package version 18-24301-9 for this replacement reference. Confirm the part number, screw style, drive or engine model, and applicable serial range before ordering.
- Designed for use with a compatible Mercury Marine gearcase drain or fill screw.
- Used as a replacement sealing washer during gearcase lubricant service.
- Replace the old washer whenever the drain or vent screw is removed for service.
Part Number References
Use the following reference to compare the replacement washer with the part removed from your gearcase.
| Reference Type | Part Number | Description |
|---|---|---|
| Mercury Marine OEM reference | 26-830749 | Drain screw gasket reference |
| Sierra catalog reference | 18-2430 | Drain screw gasket |
| Sierra package reference | 18-24301-9 | Packaged drain screw gasket version |
Engine & Model Compatibility
Compatibility depends on the exact gearcase, drive, screw configuration, and—on some applications—the engine or drive serial number. Do not rely on horsepower alone. Compare the removed washer and the applicable parts information before installation.
| Brand | Application | Reference | Compatibility Note |
|---|---|---|---|
| Mercury Marine | Compatible gearcase drain-screw applications | 26-830749 | Verify the specific model, drive, and serial-number conditions before ordering. |
| Mercury Marine | Verado applications | 26-830749 | Catalog reference identifies this drain-screw gasket replacement for All Verado; confirm the exact application before installation. |
Technical Specifications
- Product Type
- Gearcase drain screw gasket washer
- Primary Use
- Sealing a compatible lower-unit drain or fill screw during gearcase service
- OEM Reference
- Mercury Marine 26-830749
- Aftermarket Catalog References
- Sierra 18-2430 and packaged version 18-24301-9
- Installation
- Install on a compatible drain or fill screw after removing the old gasket
- Replacement Guidance
- Use a new gasket whenever the drain or vent screw is removed for service
What’s in the Box
Package quantity depends on the option selected at purchase. The product is a gasket washer; drain screws, gear lubricant, tools, and other service components are not included unless specifically stated with the selected option.
- Selected quantity of gearcase drain screw gasket washers
Installation Notes
- Place a suitable drain pan beneath the lower unit or sterndrive.
- Remove the drain or fill screw with the correct tool and remove the old gasket.
- If changing the gearcase lubricant, remove the applicable vent screw and allow the lubricant to drain according to the engine or drive service instructions.
- Inspect the drained lubricant for water contamination or metal particles before refilling.
- Clean the screw and the sealing surface. Do not reuse a damaged, flattened, or previously compressed gasket.
- Install the new gasket on the compatible screw and reinstall the screw.
- Tighten the screw to the manufacturer’s specified torque. Do not overtighten.
- Refill the gearcase with the specified lubricant and check the drain and vent screws for leakage after service.
Troubleshooting & FAQ
How do I confirm that this gasket fits?
Compare the OEM reference on your parts information or removed gasket with Mercury Marine reference 26-830749. Also verify the engine or drive model and serial-number conditions where applicable. A similar-looking washer is not sufficient proof of compatibility.
What does 26-830749 refer to?
26-830749 is the Mercury Marine OEM reference associated with this replacement drain screw gasket washer.
Is this a drain screw or a gasket?
This listing is for the gasket washer only. The drain or fill screw, gear lubricant, and service tools are not included unless expressly identified in the selected package option.
Should I reuse the old gasket?
Replacement is recommended whenever the drain or vent screw is removed. A compressed or damaged gasket may not seal correctly and can allow lubricant leakage or water intrusion.
What are the signs of a sealing problem?
Look for fresh gear lubricant around the drain or vent screw, water contamination in the lubricant, or a visibly damaged or flattened gasket. Stop and correct the seal before continued operation if leakage is found.
Is this an OEM component?
This is a replacement gasket washer for the Mercury Marine OEM reference shown above. It is not sold as a genuine Mercury Marine-branded component.
What quantity will I receive?
The quantity depends on the package option selected at purchase. Review the option title and quantity before completing the order.
When should the gasket be replaced?
Replace it during gearcase lubricant service whenever the drain or vent screw is removed, or sooner if the existing gasket shows wear, deformation, corrosion, or leakage.
Safety & Important Information
- Verify the OEM reference, application, screw configuration, and any model or serial-number requirements before purchase.
- Do not assume that every Mercury Marine or Mercruiser model uses the same drain-screw gasket.
- Follow the engine or sterndrive manufacturer’s service procedure and torque specifications.
- Professional installation is recommended if you are unfamiliar with lower-unit lubricant service.
About Sea Sierra
- Marine Parts Focus — Practical replacement components for routine maintenance and repair.
- Clear Reference Information — Product references and application notes are provided to support careful part matching.
- Worldwide Fulfillment — Shipping options and delivery estimates are shown at checkout where available.
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
