Drain Screw Gasket – Fits Mercury/Mercruiser 40-600 HP & All Models (Replaces 26-830749, 26-8M0204693)

$12.49

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Drain Screw Gasket – Fits Mercury/Mercruiser 40-600 HP & All Models (Replaces 26-830749, 26-8M0204693) is backordered and will ship as soon as it is back in stock.

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Product Details

This high-quality Drain Screw Gasket is designed for a wide range of Mercury and Mercruiser marine engines. It is compatible with most outboard models from 40 HP to 600 HP (both 2-Stroke and 4-Stroke) made from 1990–Present, as well as all sterndrive and inboard engine models manufactured from 1994–Present.

This part serves as a direct cross-reference for Mercury OEM part numbers 26-830749 and 26-8M0204693.

Material: Constructed from a tear-resistant, rubber-coated stainless steel washer for a durable seal.
Installation: Designed for use with standard 3/8"-16 drain/fill screws.
Package Contents: Includes one drain screw gasket.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand	Part Number	Superseded By
Mercury	26-830749	26-8M0204693
Mercury	26-8M0204693

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Mercury/Mercruiser Outboard Engines:

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
Mercury	40-50-60 EFI	40-60	4-Stroke	1C000001–1C050251	26-830749/26-8M0204693
Mercury	40-50-60 EFI	40-60	4-Stroke	1C050252–1C453839	26-830749/26-8M0204693
Mercury	40-50-60 EFI	40-60	4-Stroke	1C453840–Current	26-830749/26-8M0204693
Mercury	70-90 EFI	70-90	4-Stroke	2B095049–Current	26-830749/26-8M0204693
Mercury	75-90-115 Optimax	75-115	2-Stroke	1B417702–Current	26-830749/26-8M0204693	DFI Models
Mercury	115 EFI	115	4-Stroke	2B095049–Current	26-830749/26-8M0204693
Mercury	135-150-175-200 Verado	135-200	4-Stroke	All	26-830749/26-8M0204693	4-Cylinder models
Mercury	V-135 DFI	135	2-Stroke	1B417702–Up	26-830749/26-8M0204693	2.5L
Mercury	V-150 DFI	150	2-Stroke	1B417702–Up	26-830749/26-8M0204693	2.5L
Mercury	V-150 EFI	150	4-Stroke	1B227000–Up	26-830749/26-8M0204693	2.5L
Mercury	V-175 DFI	175	2-Stroke	1B417702–Up	26-830749/26-8M0204693	2.5L
Mercury	V-200 EFI	200	4-Stroke	1B227000–Up	26-830749/26-8M0204693	2.5L
Mercury	175-300 V6 & V8	175-300	4-Stroke	All	26-830749/26-8M0204693	3.4L V6 & 4.6L V8 Torpedo & Torque Master
Mercury	200-300 Verado	200-300	4-Stroke	All series	26-830749/26-8M0204693	6-cylinder models
Mercury	250-300 V8 Racing	250-300	4-Stroke	All	26-830749/26-8M0204693	Sport Master, Torpedo & Torque Master
Mercury	450 V8 Racing	450	4-Stroke	All	26-830749/26-8M0204693	Sport Master & Torpedo

Mercury/Mercruiser Sterndrive & Inboard Engines:

Brand	Model	Rated HP	Stroke	Years	OEM Part No.	Notes
MerCruiser	Alpha One (Gen.II)	All	4-Stroke	1996–1997	26-830749/26-8M0204693	0F680000-0K999999
MerCruiser	Bravo One/Two/Three	All	4-Stroke	0W250000 & Up	26-830749/26-8M0204693	All variants including X and XR
MerCruiser	Bravo XR Sportmaster	All	4-Stroke	0M906878 & Up	26-830749/26-8M0204693
MerCruiser	NXT1 Drive	All	4-Stroke	0M954569 & Up	26-830749/26-8M0204693
MerCruiser	SSM Six/Seven	All	4-Stroke	All	26-830749/26-8M0204693
MerCruiser	HI Performance Transom	All	4-Stroke	0W150003 & Up	26-830749/26-8M0204693
MerCruiser	INTEGRATED Transom	All	4-Stroke	0M052768 & Up	26-830749/26-8M0204693
MerCruiser	Zeus 3000	All	4-Stroke	All Series	26-830749/26-8M0204693	All production ranges

Technical Specs

Product Type: Drain Screw Gasket/Seal
Installation: Used with 3/8"-16 drain/fill screw
Housing Material: Rubber-coated stainless steel washer
Housing Color: Yellow
Fitting Type: Washer/Gasket
Thread Size: For 3/8"-16 drain screws
Other Technical Attributes: Tear-resistant gearcase drain screw seal

What’s in the Box

1 x Drain Screw Gasket (26-8M0204693)

Installation Notes

Ensure the engine is off and cool. Place a drain pan under the gearcase.
Remove the lower drain/fill screw and the upper vent screw. Allow the old gear lube to drain completely.
Clean the drain plug and the sealing surface on the gearcase, removing any old gasket residue.
Place the new drain screw gasket onto the drain screw.
Fill the gearcase with the recommended lubricant through the lower hole until fluid emerges from the upper vent hole.
Install the upper vent screw first, then install the lower drain screw with the new gasket. Tighten to the manufacturer's specified torque. Do not overtighten.
Clean any excess lubricant and check for leaks around both plugs.

Troubleshooting & FAQ

How do I know if this gasket fits my engine?

This gasket is designed for most Mercury/Mercruiser outboards (40+ HP) from 1990–Present and sterndrives from 1994–Present. Please review the detailed "Engine & Model Compatibility" tables on this page and compare the OEM part number (26-830749 or 26-8M0204693) to your service manual to ensure an exact match.

Is this gasket for the upper vent screw or the lower drain screw?

This gasket fits the 3/8"-16 screw, which is typically used for both the lower drain/fill plug and the upper vent plug on compatible Mercury/Mercruiser gearcases.

How often should I replace the drain screw gasket?

It is best practice to use a new gasket every time you change your gearcase lubricant. This is typically done at least once a year or every 100 hours of operation, whichever comes first, to prevent leaks and water intrusion.

What are the signs of a failing drain screw gasket?

A failing gasket can cause gear lube to leak from the drain screw. Key signs include an oily sheen on the water around your lower unit, a noticeable drop in the gear lube level, or milky/contaminated oil, which indicates water has entered the gearcase.

What is the benefit of a rubber-coated steel washer?

The design combines the best of both materials. The rubber coating provides a superior, compressible seal against the gearcase housing to prevent leaks, while the inner stainless steel washer prevents the gasket from deforming or tearing when the screw is tightened.

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

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Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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